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1

Hoback, Wyoming: Energy Resources | Open Energy Information  

Open Energy Info (EERE)

Hoback, Wyoming: Energy Resources Hoback, Wyoming: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 43.2818713°, -110.7838117° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":43.2818713,"lon":-110.7838117,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

2

TE HNOLOGY SUMMARY  

nano oral high surfa e area platinum atalysts to improve fuel ell effi ien y te hnology summary te hnology readiness level: 4 key elements have een demonstrated ...

3

TE HNOLOGY SUMMARY  

owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energys National Nuclear Security Administration. SAND # 2011-7007P TE HNOLOGY INQUIRY?

4

arXiv.org help - Why Submit the TeX/LaTeX Source?  

NLE Websites -- All DOE Office Websites (Extended Search)

abshep-th9511053). TeX source is more compact and space-efficient. Frequent Red Herring Concerns: Will the auto-TeXing embed figures? Yes. Our TeX installation can do...

5

TE Connectivity Finds Answers in Tomography  

NLE Websites -- All DOE Office Websites (Extended Search)

TE Connectivity Finds Answers in TE Connectivity Finds Answers in Tomography TE Connectivity Finds Answers in Tomography Print Thursday, 22 August 2013 10:50 TE Connectivity is a world leader in connectivity-the $13 billion global company designs and manufactures more than 500,000 different electronic connectivity products for the automotive, energy, industrial, broadband communications, consumer device, healthcare, aerospace, and defense industries. TE Connectivity has a long-standing commitment to innovation and engineering excellence. Their products help address challenges arising from companies' need for energy efficiency, always-on communications, and ever-increasing productivity. Recently, a team led by TE's senior manager of materials development, Dr. Jerzy Gazda (at left), has been investigating how ALS tomography capabilities can help the company develop more efficient connectors.

6

Recycling of CdTe photovoltaic waste  

DOE Patents (OSTI)

A method for extracting and reclaiming metals from scrap CdTe photovoltaic cells and manufacturing waste by leaching the waste with a leaching solution comprising nitric acid and water, skimming any plastic material from the top of the leaching solution, separating the glass substrate from the liquid leachate and electrolyzing the leachate to separate Cd from Te, wherein the Te is deposits onto a cathode while the Cd remains in solution.

Goozner, Robert E. (Charlotte, NC); Long, Mark O. (Charlotte, NC); Drinkard, Jr., William F. (Charlotte, NC)

1999-01-01T23:59:59.000Z

7

Response of Cds/CdTe Devices to Te Exposure of Back Contact: Preprint  

DOE Green Energy (OSTI)

Theoretical predictions of thin-film CdS/CdTe photovoltaic (PV) devices have suggested performance may be improved by reducing recombination due to Te-vacancy (VTe) or Te-interstitial (Tei) defects. Although formation of these intrinsic defects is likely influenced by CdTe deposition parameters, it also may be coupled to formation of beneficial cadmium vacancy (VCd) defects. If this is true, reducing potential effects of VTe or Tei may be difficult without also reducing the density of VCd. In contrast, post-deposition processes can sometimes afford a greater degree of defect control. Here we explore a post-deposition process that appears to influence the Te-related defects in polycrystalline CdTe. Specifically, we have exposed the CdTe surface to Te prior to ZnTe:Cu/Ti contact-interface formation with the goal of reducing VTe but without significantly reducing VCd. Initial results show that when this modified contact is used on a CdCl2-treated CdS/CdTe device, significantly poorer device performance results. This suggests two things: First, the amount of free-Te available during contact formation (either from chemical etching or CuTe or ZnTe deposition) may be a more important parameter to device performance than previously appreciated. Second, if processes have been used to reduce the effect of VTe (e.g., oxygen and chlorine additions to the CdTe), adding even a small amount of Te may produce detrimental defects.

Gessert, T. A.; Burst, J. M.; Ma, J.; Wei, S. H.; Kuciauskas, D.; Barnes, T. M.; Duenow, J. N.; Young, M. R.; Rance, W. L.; Li, J. V.; Dippo, P.

2012-06-01T23:59:59.000Z

8

Particulate Contacts to Si and CdTe: Al, Ag, Hg-Cu-Te, and Sb-Te  

DOE Green Energy (OSTI)

Our team has been investigating the use of particle-based contacts in both Si and CdTe solar cell technologies. First, in the area of contacts to Si, powders of Al and Ag prepared by an electroexplosion process have been characterized by transmission electron microscopy (TEM), TEM elemental determination X-ray spectroscopy (TEM-EDS), and TEM electron diffraction (TEM-ED). These Al and Ag particles were slurried and tested as contacts to p- and n-type silicon wafers, respectively. Linear current-voltage (I-V) was observed for Ag on n-type Si, indicative of an ohmic contact, whereas the Al on p-type Si sample was non-ideal. A wet-chemical surface treatment was performed on one Al sample and TEM-EDS indicated a substantial decrease in the O contaminant level. The treated Al on p-type Si films exhibited linear I-V after annealing. Second, in the area of contacts to CdTe, particles of Hg-Cu-Te and Sb-Te have been applied as contacts to CdTe/CdS/SnO2 heterostructures prepared by the standard NREL protocol. First, Hg-Cu-Te and Sb-Te were prepared by a metathesis reaction. After CdCl2 treatment and NP etch of the CdTe layer, particle contacts were applied. The Hg-Cu-Te contacted cells exhibited good electrical characteristics, with Voc > 810 mV and efficiencies > 11.5 % for most cells. Although Voc > 800 mV were observed for the Sb-Te contacted cells, efficiencies in these devices were limited to 9.1%, presumably by a large series resistance (>20 {Omega}) observed in all samples.

Schulz, D. L.; Ribelin, D.; Curtis, C. J.; Ginley, D. S.

1998-10-22T23:59:59.000Z

9

Synthesis of Nanowires-enhanced Bulk TE Nanocomposite for High ...  

Science Conference Proceedings (OSTI)

Abstract Scope, There are great interest in developing high-efficiency thermoelectrical (TE) materials for power generation. Significant improvements in a few TE...

10

CdSxTe1-x Alloying in CdS/CdTe Solar Cells  

DOE Green Energy (OSTI)

A CdSxTe1-x layer forms by interdiffusion of CdS and CdTe during the fabrication of thin-film CdTe photovoltaic (PV) devices. The CdSxTe1-x layer is thought to be important because it relieves strain at the CdS/CdTe interface that would otherwise exist due to the 10% lattice mismatch between these two materials. Our previous work [1] has indicated that the electrical junction is located in this interdiffused CdSxTe1-x region. Further understanding, however, is essential to predict the role of this CdSxTe1-x layer in the operation of CdS/CdTe devices. In this study, CdSxTe1-x alloy films were deposited by RF magnetron sputtering and co-evaporation from CdTe and CdS sources. Both radio-frequency-magnetron-sputtered and co-evaporated CdSxTe1-x films of lower S content (x<0.3) have a cubic zincblende (ZB) structure akin to CdTe, while those of higher S content have a hexagonal wurtzite (WZ) structure like that of CdS. Films become less preferentially oriented as a result of a CdCl2 heat treatment at ~400 degrees C for 5 min. Films sputtered in a 1% O2/Ar ambient are amorphous as deposited, but show CdTe ZB, CdS WZ, and CdTe oxide phases after a CdCl2 heat treatment (HT). Films sputtered in O2 partial pressure have a much wider bandgap (BG) than expected. This may be explained by nanocrystalline size effects seen previously [2] for sputtered oxygenated CdS (CdS:O) films.

Duenow, J. N.; Dhere, R. G.; Moutinho, H. R.; To, B.; Pankow, J. W.; Kuciauskas, D.; Gessert, T. A.

2011-05-01T23:59:59.000Z

11

Double-{beta}-decay Q values of {sup 130}Te, {sup 128}Te, and {sup 120}Te  

SciTech Connect

The double-{beta}-decay Q values of {sup 130}Te, {sup 128}Te, and {sup 120}Te have been determined from parent-daughter mass differences measured with the Canadian Penning Trap mass spectrometer. The {sup 132}Xe-{sup 129}Xe mass difference, which is precisely known, was also determined to confirm the accuracy of these results. The {sup 130}Te Q value was found to be 2527.01{+-}0.32 keV, which is 3.3 keV lower than the 2003 Atomic Mass Evaluation recommended value and is consistent with another recent Penning trap measurement. The {sup 128}Te and {sup 120}Te Q values were found to be 865.87{+-}1.31 and 1714.81{+-}1.25 keV, respectively. For {sup 120}Te, this reduction in uncertainty of nearly a factor of 8 opens up the possibility of using this isotope for sensitive searches for neutrinoless double-electron capture and electron capture with {beta}{sup +}emission.

Scielzo, N. D. [Physical Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Caldwell, S.; Savard, G.; Sternberg, M.; Van Schelt, J. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Physics, University of Chicago, Chicago, Illinois 60637 (United States); Clark, J. A.; Levand, A. F.; Sun, T. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Deibel, C. M. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Joint Institute of Nuclear Astrophysics, Michigan State University, East Lansing, Michigan 48824 (United States); Fallis, J. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Gulick, S. [Department of Physics, McGill University, Montreal, Quebec H3A 2T8 (Canada); Lascar, D. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208 (United States); Li, G. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Physics, McGill University, Montreal, Quebec H3A 2T8 (Canada); Mintz, J. [Department of Nuclear Engineering, University of California, Berkeley, California 94720 (United States); Norman, E. B. [Physical Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Department of Nuclear Engineering, University of California, Berkeley, California 94720 (United States); Sharma, K. S. [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada)

2009-08-15T23:59:59.000Z

12

Recycling of CdTe photovoltaic waste  

DOE Patents (OSTI)

A method for extracting and reclaiming metals from scrap CdTe photovoltaic cells and manufacturing waste by leaching the metals in dilute nitric acid, leaching the waste with a leaching solution comprising nitric acid and water, skimming any plastic material from the top of the leaching solution, separating the glass substrate from the liquid leachate, adding a calcium containing base to the leachate to precipitate Cd and Te, separating the precipitated Cd and Te from the leachate, and recovering the calcium-containing base.

Goozner, Robert E. (Charlotte, NC); Long, Mark O. (Charlotte, NC); Drinkard, Jr., William F. (Charlotte, NC)

1999-04-27T23:59:59.000Z

13

Recycling of CdTe photovoltaic waste  

DOE Patents (OSTI)

A method for extracting and reclaiming metals from scrap CdTe photovoltaic cells and manufacturing waste by leaching the metals in dilute nitric acid, leaching the waste with a leaching solution comprising nitric acid and water, skimming any plastic material from the top of the leaching solution, separating the glass substrate from the liquid leachate, adding a calcium containing base to the leachate to precipitate Cd and Te, separating the precipitated Cd and Te from the leachate, and recovering the calcium-containing base. 3 figs.

Goozner, R.E.; Long, M.O.; Drinkard, W.F. Jr.

1999-04-27T23:59:59.000Z

14

Thermodynamic and Transport Properties of YTe3, LaTe3 and CeTe3  

SciTech Connect

Measurements of heat capacity, susceptibility, and electrical resistivity are presented for single crystals of the charge density wave compounds YTe{sub 3}, LaTe{sub 3}, and CeTe{sub 3}. The materials are metallic to low temperatures, but have a small density of states due to the charge density wave gapping large portions of the Fermi surface. CeTe{sub 3} is found to be a weak Kondo lattice, with an antiferromagnetic ground state and T{sub N} = 2.8 K. The electrical resistivity of all three compounds is highly anisotropic, confirming the weak dispersion perpendicular to Te planes predicted by band structure calculations.

Ru, N.

2011-08-19T23:59:59.000Z

15

IMPROVEMENT OF CdMnTe DETECTOR PERFORMANCE BY MnTe PURIFICATION  

Science Conference Proceedings (OSTI)

Residual impurities in manganese (Mn) are a big obstacle to obtaining high-performance CdMnTe (CMT) X-ray and gamma-ray detectors. Generally, the zone-refining method is an effective way to improve the material's purity. In this work, we purified the MnTe compounds combining the zone-refining method with molten Te, which has a very high solubility for most impurities. We confirmed the improved purity of the material by glow-discharge mass spectrometry (GDMS). We also found that CMT crystals from a multiply-refined MnTe source, grown by the vertical Bridgman method, yielded better performing detectors.

Kim, K.H.; Bolotnikov, A.E.; Camarda, G.S.; Tappero, R.; Hossain, A.; Cui, Y.; Yang, G.; Gul, R.; and James, R.B.

2011-04-25T23:59:59.000Z

16

AOCS Official Method Te 3a-64  

Science Conference Proceedings (OSTI)

Acid Value and Free Amine Value of Fatty Quaternary Ammonium Chlorides AOCS Official Method Te 3a-64 Methods Downloads Methods Downloads DEFINITION The acid value is the mg of potassium hydroxide necessary to neut

17

Substrate CdTe Efficiency Improvements  

Thin film solar cells have been the focus of many research facilities in recent years that are working to decrease manufacturing costs and increase cell efficiency. Cadmium telluride (CdTe) has been well recognized as a promising photovoltaic material ...

18

AOCS Official Method Te 4a-70  

Science Conference Proceedings (OSTI)

Acid Value AOCS Official Method Te 4a-70 Methods Downloads Methods Downloads DEFINITION The acid value is the mg of potassium hydroxide necessary to neutralize the free acids in 1 g of test sample.

19

Perspective on TeV-scale physics  

Science Conference Proceedings (OSTI)

These lectures review theoretical motivations and experimental prospects for the study of TeV-scale physics. Three clues to the importance of TeV physics are discussed: implications of quantum corrections for the masses of a fourth generation quark-lepton family, the gauge hierarchy problem and known solutions, and implications of symmetry and unitarity for the symmetry-breaking sector of the electroweak gauge theory. The experimental prospects are reviewed with emphasis on the multi-TeV pp colliders that may be built in the 1990's. The topics include new phenomena that might occur - e.g., a fourth generation, heavy gauge bosons, composite structure, and supersymmetry - as well as the signals of the unknown SU(2)/sub L/ /times/ U(1)/sub Y/ breaking mechanism that must occur within the TeV domain. 96 refs., 21 figs.

Chanowitz, M.S.

1989-02-01T23:59:59.000Z

20

LaTeX Paper - TMS  

Science Conference Proceedings (OSTI)

LaTeX PAPER TMS1, Jane Doe2, John Doe2 1TMS (The Minerals Metals & Materials Society)184 Thorn Hill Rd.; Warrendale, PA 15086-7514, USA 2Name of...

Note: This page contains sample records for the topic "graphi te hoback" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

AOCS Official Method Te 1a-64  

Science Conference Proceedings (OSTI)

Acid Value AOCS Official Method Te 1a-64 Methods Downloads Methods Downloads DEFINITION The acid value is the mg of potassium hydroxide necessary to neutralize fatty acids in 1 g of test sample. SCO

22

AOCS Official Method Te 2a-64  

Science Conference Proceedings (OSTI)

Color, Photometric Index AOCS Official Method Te 2a-64 Methods Downloads Methods Downloads DEFINITION This method measures the color of commercial fatty acids and expresses the color as percent transmission at 440

23

GaTe semiconductor for radiation detection  

SciTech Connect

GaTe semiconductor is used as a room-temperature radiation detector. GaTe has useful properties for radiation detectors: ideal bandgap, favorable mobilities, low melting point (no evaporation), non-hygroscopic nature, and availability of high-purity starting materials. The detector can be used, e.g., for detection of illicit nuclear weapons and radiological dispersed devices at ports of entry, in cities, and off shore and for determination of medical isotopes present in a patient.

Payne, Stephen A. (Castro Valley, CA); Burger, Arnold (Nashville, TN); Mandal, Krishna C. (Ashland, MA)

2009-06-23T23:59:59.000Z

24

The TE Wave Transmission Method for Electron Cloud Measurements at Cesr-TA  

E-Print Network (OSTI)

CBP-836 THE TE WAVE TRANSMISSION METHOD FOR ELECTRON CLOUDobtained using the TE transmission technique described inBesides the TE transmission method in its initial

Desantis, S.

2010-01-01T23:59:59.000Z

25

Impurity Gettering Effect of Te Inclusions in Cdznte Single Crystals  

Science Conference Proceedings (OSTI)

The local impurity distribution in Te inclusions of CdZnTe (CZT) crystal was investigated by the time-of-flight secondary ion mass spectrometry (Tof-SIMS) technique. Direct evidence of impurity gettering in Te inclusions has been observed for the first time. The impurity gettering in Te inclusions originated from the diffusion mechanism during crystal growth and segregation mechanism during crystal cooling. This phenomenon is meaningful, because it reveals how Te inclusions affect CZT properties and provides a possible approach to reduce the impurities in CZT by the way of removing Te inclusions.

Yang, G.; Bolotnikov, A; Cui, Y; Camarda, G; Hossain, A; James, R

2009-01-01T23:59:59.000Z

26

INTEGRAL observations of TeV plerions  

E-Print Network (OSTI)

Amongst the sources seen in very high gamma-rays several are associated with Pulsar Wind Nebulae (``TeV plerions''). The study of hard X-ray/soft gamma-ray emission is providing an important insight into the energetic particle population present in these objects. The unpulsed emission from pulsar/pulsar wind nebula systems in the energy range accessible to the INTEGRAL satellite is mainly synchrotron emission from energetic and fast cooling electrons close to their acceleration site. Our analyses of public INTEGRAL data of known TeV plerions detected by ground based Cherenkov telescopes indicate a deeper link between these TeV plerions and INTEGRAL detected pulsar wind nebulae. The newly discovered TeV plerion in the northern wing of the Kookaburra region (G313.3+0.6 powered by the middle aged PSR J1420-6048) is found to have a previously unknown INTEGRAL counterpart which is besides the Vela pulsar the only middle aged pulsar detected with INTEGRAL. We do not find an INTEGRAL counterpart of the TeV plerion associated with the X-ray PWN ``Rabbit'' G313.3+0.1 which is possibly powered by a young pulsar.

A. I. D. Hoffmann; D. Horns; A. Santangelo

2006-09-14T23:59:59.000Z

27

ALTERNATING URRENT PHOTOVOLTAI UILDING LO K TE HNOLOGY ...  

Solar Energy Generation Energy Storage Power Sources Satellites TE HNOLOGI AL ENEFITS module technologies Eliminates D voltage concerns

28

Search for ? + / EC double beta decay of 120 Te  

Science Conference Proceedings (OSTI)

We present a search for ? + / EC double beta decay of 120 Te performed with the CUORICINO experiment

C. Tomei; The CUORICINO Collaboration

2011-01-01T23:59:59.000Z

29

Novel Method for Growing Te-Inclusion-Free CZT  

Science Conference Proceedings (OSTI)

The authors propose a new method for growth of detector-grade CdZnTe (CZT) with reduced concentration and sizes of Te inclusions. The method is designed to impede the formation of Te-rich inclusions in crystals due to the use of new CZT growth method and a unique ampoule design.

Bolotnikov,A.

2008-06-17T23:59:59.000Z

30

ZnO-ZnTe Nanocone Heterojunctions  

Science Conference Proceedings (OSTI)

Semiconductor nanostructure heterojunctions are expected to be efficient structures for next-generation photovoltaic solar cells, radiation detectors, and light-emitting diodes. In this letter we report heterojunctions made of vertically aligned ZnO/ZnTe nanocones synthesized using a combination of thermal vapor deposition and pulsed-laser deposition (PLD). The ZnO nanocones and nanorods were synthesized as cores by utilizing the growth rate difference between central and boundary sites of precursor domains during thermal vapor deposition. The p-n heterojunctions were subsequently formed by growing ZnTe as shells on the nanocone surface using PLD. The ZnTe shells were polycrystalline structures, while ZnO cores were wurzite structures. The p-n junction of the nanocone core-shell structure exhibited I-V characteristics consistent with a p-n diode, but the nanorod junction did not. These structural and electric characteristics indicate that the ZnO nanocones are more feasible than ZnO nanorods as heterojunctions because the sloping facets of the nanocones facilitate deposition of ZnTe by PLD without the deleterious effects of shadowing. Furthermore, based on theoretical modeling of nanostructure heterojunctions, the nanocone-based junction exhibits an electrostatic potential profile that is much more effective for carrier transport than the electrostatic potential for the nanorod-based junction.

Lee, Sang Hyun [ORNL; Smith, Barton [ORNL; Zhang, Xiaoguang [ORNL; Seo, Sung Seok A [ORNL; Bell, Zane W [ORNL; Xu, Jun [ORNL

2010-01-01T23:59:59.000Z

31

Mechanism of terahertz photoconductivity in semimetallic HgTe/CdHgTe quantum wells  

Science Conference Proceedings (OSTI)

Terahertz photoconductivity in magnetic fields in semimetallic HgTe/CdHgTe quantum wells has been studied. The main contribution to photoconductivity comes from a signal that appears as a result of electron-gas heating. It is shown that, with the cyclotron resonance conditions satisfied, the photoconductivity signal is composed of cyclotron-resonance and bolometric components. However, in this case too, the bolometric contribution predominates.

Vasilyev, Yu. B., E-mail: yu.vasilyev@mail.ioffe.ru [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation); Mikhailov, N. N. [Russian Academy of Sciences, Rzhanov Institute of Semiconductor Physics, Siberian Branch (Russian Federation); Gouider, F. [Institut fuer Angewandte Physik (Germany); Vasilyeva, G. Yu. [St. Petersburg State Polytechnic University (Russian Federation); Nachtwei, G. [Institut fuer Angewandte Physik (Germany)

2012-05-15T23:59:59.000Z

32

THE PERFORMANCE OF THIN FILM SOLAR CELLS EMPLOYING PHOTOVOLTAIC Cu22014x Te-CdTe HETEROJUNCTIONS (1)  

E-Print Network (OSTI)

195 THE PERFORMANCE OF THIN FILM SOLAR CELLS EMPLOYING PHOTOVOLTAIC Cu22014x Te This paper is a short status report on the continuing development of Cu22014xTe-CdTe thin film solar cells thin film work. The most pressing current need is to determine how to extend cell life, particularly

Paris-Sud XI, Université de

33

Preferential orientation of Te precipitates in melt-grown CZT  

Science Conference Proceedings (OSTI)

Cadmium zinc telluride (Cd1-xZnxTe or CZT) has proved to be a useful material for semiconductor gamma-ray spectrometers and other electro-optic devices. It is often grown Te-rich to optimize its electrical characteristics, but this off-stoichiometric growth leads to the formation of semimetallic Te precipitates in the semiconducting host crystal. These precipitates can impair device performance and their formation needs to be inhibited, if possible, during growth. Characterization of melt-grown CZT has shown that Te precipitates are often faceted. In this study, characterization of several particles of different shapes revealed that most of the Te precipitates were preferentially oriented with the {101}CZT||{-12-10}Te . A secondary orientation relationship was also observed as {11-1}CZT||{01-11}Te for one of the {111}CZT family of planes. One of the particles exhibited {110}CZT||{01-10}Te and {001}CZT||{0001}Te . Precipitates were often found on {111}CZT twin boundaries and, in these cases, it was possible to assign specific orientations with respect to the twin plane. The expected orientation of the {0001}-plane of Te aligned with the {111}-plane of CZT was not observed even though a good lattice match is predicted in ab initio models. Observations of strained and polycrystalline Te precipitates are also discussed with relevance to the ab initio model and to impacts on electronic properties.

Henager, Charles H.; Edwards, Danny J.; Schemer-Kohrn, Alan L.; Bliss, Mary; Jaffe, John E.

2009-05-18T23:59:59.000Z

34

CdTe PV: Real and Perceived EHS Risks  

DOE Green Energy (OSTI)

As CdTe photovoltaics reached commercialization, questions have been raised about potential cadmium emissions from CdTe PV modules. Some have attacked the CdTe PV technology as unavoidably polluting the environment, and made comparisons of hypothetical emissions from PV modules to cadmium emissions from coal fired power plants. This paper gives an overview of the technical issues pertinent to these questions and further explores the potential of EHS risks during production, use and decommissioning of CdTe PV modules. The following issues are discussed: (a) The physical and toxicological properties of CdTe, (b) comparisons of Cd use in CdTe PV with its use in other technologies and products, and the (c) the possibility of CdTe releases from PV modules.

Fthenakis, V.; Zweibel, K.

2003-05-01T23:59:59.000Z

35

Spectroscopic Cathodoluminescence Studies of the ZnTe:Cu Contact Process for CdS/CdTe Solar Cells: Preprint  

DOE Green Energy (OSTI)

This conference paper describes the spectroscopic cathodoluminescence (CL), electron-beam induced current (EBIC), and capacitance-Voltage (C-V) measurements are used to study the formation of CdS/CdTe devices processed using ion-beam milling and a ZnTe:Cu/Ti contact. Results show heating in vacuum at {approx}360 C and ion-beam milling lead to observable changes in the CL emission from the CdCl2-treated CdTe surface. Changes in the CL spectrum are also observed as ZnTe:Cu layer thickness increases. These changes are correlated to published studies of defect levels and shown to be due, possibly, to an n-type region existing between the ZnTe:Cu contact interface and the p-CdTe layers. This n-type region is eliminated once a sufficiently thick ZnTe:Cu layer is produced.

Gessert, T. A.; Romero, M. J.; Johnston, S.; Keyes, B.; Dippo, P.

2002-05-01T23:59:59.000Z

36

CdZnTe technology for gamma ray detectors  

Science Conference Proceedings (OSTI)

CdZnTe detector technology has been developed at NASA Goddard for imaging and spectroscopy applications in hard x-ray and gamma ray astronomy. A CdZnTe strip detector array with capabilities for arc second imaging and spectroscopy has been built as a prototype for a space flight gamma ray burst instrument. CdZnTe detectors also have applications for medical imaging

Carl Stahle; Jack Shi; Peter Shu; Scott Barthelmy; Ann Parsons; Steve Snodgrass

1998-01-01T23:59:59.000Z

37

Liquidus Projection of Thermoelectric Ag-Sn-Te Ternary System  

Science Conference Proceedings (OSTI)

Presentation Title, Liquidus Projection of Thermoelectric Ag-Sn-Te Ternary ... Ag Decorated Al Nanoparticles as Novel Ink Materials for Printed Electronics...

38

X-ray luminescence of CdTe quantum dots in LaF{sub 3}:Ce/CdTe nanocomposites  

Science Conference Proceedings (OSTI)

CdTe quantum dots have intense photoluminescence but exhibit almost no x-ray luminescence. However, intense x-ray luminescence from CdTe quantum dots is observed in LaF{sub 3}:Ce/CdTe nanocomposites. This enhancement in the x-ray luminescence of CdTe quantum dots is attributed to the energy transfer from LaF{sub 3}:Ce to CdTe quantum dots in the nanocomposites. The combination of LaF{sub 3}:Ce nanoparticles and CdTe quantum dots makes LaF{sub 3}:Ce/CdTe nanocomposites promising scintillators for radiation detection.

Hossu, Marius; Liu Zhongxin; Yao Mingzhen; Ma Lun; Chen Wei

2012-01-02T23:59:59.000Z

39

CdS/CdTe Solar Cells Containing Directly Deposited CdSxTe1-x Alloy Layers: Preprint  

DOE Green Energy (OSTI)

A CdSxTe1-x layer forms by interdiffusion of CdS and CdTe during the fabrication of thin-film CdTe photovoltaic (PV) devices. The CdSxTe1-x layer is thought to be important because it relieves strain at the CdS/CdTe interface that would otherwise exist due to the 10% lattice mismatch between these two materials. Our previous work [1] has indicated that the electrical junction is located in this interdiffused CdSxTe1-x region. Further understanding, however, is essential to predict the role of this CdSxTe1-x layer in the operation of CdS/CdTe devices. In this study, CdSxTe1-x alloy films were deposited by radio-frequency (RF) magnetron sputtering and co-evaporation from CdTe and CdS sources. Both RF-magnetron-sputtered and co-evaporated CdSxTe1-x films of lower S content (x<0.3) have a cubic zincblende (ZB) structure akin to CdTe, whereas those of higher S content have a hexagonal wurtzite (WZ) structure like that of CdS. Films become less preferentially oriented as a result of a CdCl2 heat treatment (HT) at ~400 degrees C for 5 min. Films sputtered in a 1% O2/Ar ambient are amorphous as deposited, but show CdTe ZB, CdS WZ, and CdTe oxide phases after a CdCl2 HT. Films sputtered in O2 partial pressure have a much wider bandgap than expected. This may be explained by nanocrystalline size effects seen previously [2] for sputtered oxygenated CdS (CdS:O) films. Initial PV device results show that the introduction of a directly-deposited CdSxTe1-x alloy layer into the device structure produces devices of comparable performance to those without the alloy layer when a CdCl2 HT is performed. Further investigation is required to determine whether the CdCl2 heat treatment step can be altered or eliminated through direct deposition of the alloy layer.

Duenow, J. N.; Dhere, R. G.; Moutinho, H. R.; To, B.; Pankow, J. W.; Kuciauskas, D.; Gessert, T. A.

2011-07-01T23:59:59.000Z

40

Excited quark production at a 100 TeV VLHC  

E-Print Network (OSTI)

I look for a dijet resonance produced by an excited quark q* in a simulated sample corresponding to 3 ab^{-1} of pp collisions at $\\sqrt{s} = 100$ TeV. Using a cut and count analysis approach I demonstrate the potential to explore q* masses up to 50 TeV, corresponding to a length scale of around 4 am.

Jacob Anderson

2013-09-03T23:59:59.000Z

Note: This page contains sample records for the topic "graphi te hoback" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Excited quark production at a 100 TeV VLHC  

E-Print Network (OSTI)

I look for a dijet resonance produced by an excited quark q* in a simulated sample corresponding to 3 ab^{-1} of pp collisions at $\\sqrt{s} = 100$ TeV. Using a cut and count analysis approach I am able to explore q* masses up to 50 TeV, corresponding to a length scale of around 4 am.

Anderson, Jacob

2013-01-01T23:59:59.000Z

42

Laser irradiation effects on the CdTe/ZnTe quantum dot structure studied by Raman and AFM spectroscopy  

SciTech Connect

Micro-Raman spectroscopy has been applied to investigate the impact of laser irradiation on semiconducting CdTe/ZnTe quantum dots (QDs) structures. A reference sample (without dots) was also studied for comparison. Both samples were grown by molecular beam epitaxy technique on the p-type GaAs substrate. The Raman spectra have been recorded for different time of a laser exposure and for various laser powers. The spectra for both samples exhibit peak related to the localized longitudinal (LO) ZnTe phonon of a wavenumber equal to 210 cm{sup -1}. For the QD sample, a broad band corresponding to the LO CdTe phonon related to the QD-layer appears at a wavenumber of 160 cm{sup -1}. With increasing time of a laser beam exposure and laser power, the spectra get dominated by tellurium-related peaks appearing at wavenumbers around 120 cm{sup -1} and 140 cm{sup -1}. Simultaneously, the ZnTe surface undergoes rising damage, with the formation of Te aggregates at the pinhole edge as reveal atomic force microscopy observations. Local temperature of irradiated region has been estimated from the anti-Stokes/Stokes ratio of the Te modes intensity and it was found to be close or exceeding ZnTe melting point. Thus, the laser damage can be explained by the ablation process.

Zielony, E.; Placzek-Popko, E.; Henrykowski, A.; Gumienny, Z.; Kamyczek, P.; Jacak, J. [Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland); Nowakowski, P.; Karczewski, G. [Institute of Physics, Polish Academy of Sciences, al. Lotnikow 32/46, 02-668 Warsaw (Poland)

2012-09-15T23:59:59.000Z

43

Use of separate ZnTe interface layers to form OHMIC contacts to p-CdTe films  

DOE Patents (OSTI)

A method of improving electrical contact to a thin film of a p-type tellurium-containing II-VI semiconductor comprising: depositing a first undoped layer of ZnTe on a thin film of p-type tellurium containing II-VI semiconductor with material properties selected to limit the formation of potential barriers at the interface between the p-CdTe and the undoped layer, to a thickness sufficient to control diffusion of the metallic-doped ZnTe into the p-type tellurim-containing II-VI semiconductor, but thin enough to minimize affects of series resistance; depositing a second heavy doped p-type ZnTe layer to the first layer using an appropriate dopant; and depositing an appropriate metal onto the outer-most surface of the doped ZnTe layer for connecting an external electrical conductor to an ohmic contact.

Gessert, Timothy A. (Conifer, CO)

1999-01-01T23:59:59.000Z

44

Effects of Te inclusions on the performance of CdZnTe radiation detectors  

Science Conference Proceedings (OSTI)

Te inclusions existing at high concentrations in CdZnTe (CZT) material can degrade the performance of CZT detectors. These microscopic defects trap the free electrons generated by incident radiation, so entailing significant fluctuations in the total collected charge and thereby strongly affecting the energy resolution of thick (long-drift) detectors. Such effects were demonstrated in thin planar detectors, and, in many cases, they proved to be the dominant cause of the low performance of thick detectors, wherein the fluctuations in the charge losses accumulate along the charge's drift path. We continued studying this effect using different tools and techniques. We employed a dedicated beamline recently established at BNL's National Synchrotron Light Source for characterizing semiconductor radiation detectors, along with an IR transmission microscope system, the combination of which allowed us to correlate the concentration of defects with the devices performances. We present here our new results from testing over 50 CZT samples grown by different techniques. Our goals are to establish tolerable limits on the size and concentrations of these detrimental Te inclusions in CZT material, and to provide feedback to crystal growers to reduce their numbers in the material.

Bolotnikov,A.E.; Abdul-Jabber, N. M.; Babalola, O. S.; Camarda, G. S.; Cui, Y.; Hossain, A. M.; Jackson, E. M.; Jackson, H. C.; James, J. A.; Kohman, K. T.; Luryi, A. L.; James, R. B.

2008-10-19T23:59:59.000Z

45

Process Development for High Voc CdTe Solar Cells  

DOE Green Energy (OSTI)

This is a cumulative and final report for Phases I, II and III of this NREL funded project (subcontract # XXL-5-44205-10). The main research activities of this project focused on the open-circuit voltage of the CdTe thin film solar cells. Although, thin film CdTe continues to be one of the leading materials for large-scale cost-effective production of photovoltaics, the efficiency of the CdTe solar cells have been stagnant for the last few years. This report describes and summarizes the results for this 3-year research project.

Ferekides, C. S.; Morel, D. L.

2011-05-01T23:59:59.000Z

46

Formation of ZnTe:Cu/Ti Contacts at High Temperature for CdS/CdTe Devices: Preprint  

DOE Green Energy (OSTI)

We study the performance of CdS/CdTe thin-film devices contacted with ZnTe:Cu/Ti of various thickness at a higher-than-optimum temperature of {approx}360 C. At this temperature, optimum device performance requires the same thickness of ZnTe:Cu as for similar contacts formed at a lower temperature of 320 C. C-V analysis indicates that a ZnTe:Cu layer thickness of {approx}< 0.5 mu m does not yield the degree of CdTe net acceptor concentration necessary to reduce space charge width to its optimum value for n-p device operation. The thickest ZnTe:Cu layer investigated (1 mu m) yields the highest CdTe net acceptor concentration, lowest value of Jo, and highest Voc. However, performance is limited for this device by poor fill factor. We suggest poor fill factor is due to Cu-related acceptors compensating donors in CdS.

Gessert, T. A.; Asher, S.; Johnston, S.; Duda, A.; Young, M. R.; Moriarty, T.

2006-05-01T23:59:59.000Z

47

CdTe portfolio offers commercial ready high efficiency solar ...  

This characteristic is due partly to the single-phase nature of the absorber layer and the ease with which the CdTe source ... Wind Energy; Partners (27) Visual ...

48

Advances in CdTe R&D at NREL  

DOE Green Energy (OSTI)

This paper summarizes the following R&D accomplishments at National Renewable Energy Laboratory (NREL): (1) Developed several novel materials and world-record high-efficiency CdTe solar cell, (2) Developed "one heat-up step" manufacturing processes, and (3) Demonstrated 13.9% transparent CdTe cell and 15.3% CdTe/CIS polycrystalline tandem solar cell. Cadmium telluride has been well recognized as a promising photovoltaic material for thin-film solar cells because of its near-optimum bandgap of ~1.5 eV and its high absorption coefficient. Impressive results have been achieved in the past few years for polycrystalline CdTe thin-film solar cells at NREL. In this paper, we summarize some recent R&D activities at NREL.

Wu, X.; Zhou, J.; Keane, J. C.; Dhere, R. G.; Albin, D. S.; Gessert, T. A.; DeHart, C.; Duda, A.; Ward, J. J.; Yan, Y.; Teeter, G.; Levi, D. H.; Asher, S.; Perkins, C.; Moutinho, H. R.; To, B.

2005-11-01T23:59:59.000Z

49

Extreme solid state refrigeration using nanostructured Bi-Te alloys.  

SciTech Connect

Materials are desperately needed for cryogenic solid state refrigeration. We have investigated nanostructured Bi-Te alloys for their potential use in Ettingshausen refrigeration to liquid nitrogen temperatures. These alloys form alternating layers of Bi{sub 2} and Bi{sub 2}Te{sub 3} blocks in equilibrium. The composition Bi{sub 4}Te{sub 3} was identified as having the greatest potential for having a high Ettingshausen figure of merit. Both single crystal and polycrystalline forms of this material were synthesized. After evaluating the Ettingshausen figure of merit for a large, high quality polycrystal, we simulated the limits of practical refrigeration in this material from 200 to 77 K using a simple device model. The band structure was also computed and compared to experiments. We discuss the crystal growth, transport physics, and practical refrigeration potential of Bi-Te alloys.

Lima Sharma, Ana L. (San Jose State University, San Jose, CA); Spataru, Dan Catalin; Medlin, Douglas L.; Sharma, Peter Anand; Morales, Alfredo Martin

2009-09-01T23:59:59.000Z

50

Synthesis and characterization of ZnTe hierarchical nanostructures  

Science Conference Proceedings (OSTI)

Single-crystalline ZnTe hierarchical nanostructures have been successfully synthesized by a simple thermal evaporation technology. The as-prepared products were characterized with X-ray diffraction (XRD), scanning electron microcopy (SEM), transmission ...

Baohua Zhang; Fuqiang Guo; Wei Wang

2012-01-01T23:59:59.000Z

51

Supply Chain Dynamics of Tellurium (Te), Indium (In), and Gallium...  

NLE Websites -- All DOE Office Websites (Extended Search)

CdTe Solar Cells, Solar Energy Materials and Solar Cells, 90 (2006) 2263-2271. 3 CRC Handbook of Chemistry and Physics, CRC Press, Boca Raton, FL, 1986. 4 M.A. Green, K....

52

VUV Detector Calibrations - CsTe Photodiode Description  

Science Conference Proceedings (OSTI)

... telluride (CsTe) photodetectors with magnesium fluoride (MgF 2 ) windows are issued by ... telluride film is deposited onto a MgF 2 window and then ...

2011-12-30T23:59:59.000Z

53

Strategies for recycling CdTe photovoltaic modules  

DOE Green Energy (OSTI)

Recycling end-of-life cadmium telluride (CdTe) photovoltaic (PV) modules may enhance the competitive advantage of CdTe PV in the marketplace, but the experiences of industries with comparable Environmental, Health and Safety (EH&S) challenges suggest that collection and recycling costs can impose significant economic burdens. Customer cooperation and pending changes to US Federal law may improve recycling economics.

Eberspacher, C.; Gay, C.F. [UNISUN, Newbury Park, CA. (United States); Moskowitz, P.D. [Brookhaven National Lab., Upton, NY (United States)

1994-12-31T23:59:59.000Z

54

Effect of Heating, Ion-Beam Milling, and ZnTe:Cu Deposition on the Spectroscopic Cathodoluminescence of Polycrystalline CdTe: Preprint  

DOE Green Energy (OSTI)

Presented at the 2001 NCPV Program Review Meeting: Cathodoluminescence used to study evolution of electro-optical properties of back surface of CdS/CdTe during initial steps of fabricating NREL ZnTe:Cu contact.

Gessert, T. A.; Romero, M. J.; Asher, S. E.

2001-10-01T23:59:59.000Z

55

Phonon conduction in PbSe, PbTe, and PbTe1?xSex from first-principles calculations  

E-Print Network (OSTI)

We apply first-principles calculations to lead selenide (PbSe) and lead telluride (PbTe) and their alloys (PbTe[subscript 1?x]Se[subscript x]), which are potentially good thermoelectric materials, to investigate their ...

Tian, Zhiting

56

A simple and efficient method for synthesizing te nanowires from CdTe nanoparticles with EDTA as shape controller under hydrothermal condition  

Science Conference Proceedings (OSTI)

We developed a simple and efficient method for synthesizing Te nanowires from CdTe nanoparticles with ethylenediaminetetraacetic acid disodium salt dehydrate (EDTA) as shape controller under hydrothermal condition. The systemcould both complete the transformation ...

Fangfang Xue; Ning Bi; Jiangong Liang; Heyou Han

2012-01-01T23:59:59.000Z

57

Effects of Cu Diffusion from ZnTe:Cu/Ti Contacts on Carrier Lifetime of CdS/CdTe Thin Film Solar Cells: Preprint  

DOE Green Energy (OSTI)

We study the performance of CdS/CdTe thin film PV devices processed with a ZnTe:Cu/Ti contact to investigate how carrier lifetime in the CdTe layer is affected by Cu diffusion from the contact.

Gessert, T. A.; Metzger, W. K.; Asher, S. E.; Young, M. R.; Johnston, S.; Dhere, R. G.; Duda, A.

2008-05-01T23:59:59.000Z

58

High pressure transport characteristics of Bi[subscript 2]Te[subscript 3], Sb[subscript 2]Te[subscript 3], and BiSbTe[subscript 3  

Science Conference Proceedings (OSTI)

This paper presents ambient and high pressure measurements of transport properties of the Bi2Te3-Sb2Te3 series of materials. The electrical resistivity, thermal conductivity, and Seebeck coefficient have been measured on both end compounds and the direct solid solution of the two at pressure up to 10 GPa. An additional discussion involving the high pressure structure will be presented. From this, it was determined that these materials undergo at least two structural phase transitions between 0 and 20 GPa and a discussion is presented regarding this and the changes in the transport properties.

Jacobsen, M.K.; Sinogeikin, S.V.; Kumar, R.S.; Cornelius, A.L. (UNLV); (CIW)

2012-07-25T23:59:59.000Z

59

Electrical Characterization of Cu Composition Effects in CdS/CdTe Thin-Film Solar Cells with a ZnTe:Cu Back Contact: Preprint  

DOE Green Energy (OSTI)

We study the effects of Cu composition on the CdTe/ZnTe:Cu back contact and the bulk CdTe. For the back contact, its potential barrier decreases with Cu concentration while its saturation current density increases. For the bulk CdTe, the hole density increases with Cu concentration. We identify a Cu-related deep level at {approx}0.55 eV whose concentration is significant when the Cu concentration is high. The device performance, which initially increases with Cu concentration then decreases, reflects the interplay between the positive influences and negative influences (increasing deep levels in CdTe) of Cu.

Li, J. V.; Duenow, J. N.; Kuciauskas, D.; Kanevce, A.; Dhere, R. G.; Young, M. R.; Levi, D. H.

2012-07-01T23:59:59.000Z

60

The half-life of {sup 131g,m}Te  

SciTech Connect

In this work, the half-lives of {sup 131m}Te and {sup 131g}Te were measured. Radioactive sources of {sup 131}Te were obtained using the {sup 130}Te(n,{gamma}){sup 131}Te nuclear reaction. These nuclear parameters have been determined with a better confidence and accuracy than previously available: 18.89 {+-} 0.11 min and 33.18 {+-} 0.13 h, respectively. These results are quite helpful for new calculations that attempt to describe the low-lying levels in {sup 131}I from the decay of {sup 131g,m}Te.

Ruivo, J. C.; Zamboni, C. B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN / CNEN - SP) Av. Professor Lineu Prestes 2242 05508-000 Sao Paulo, SP (Brazil); Oliveira, J. R. B. [Instituto de Fisica da Universidade de Sao Paulo, Brazil Travessa R da Rua do Matao 187 05508-090 Sao Paulo, SP (Brazil); Heder Medina, Nilberto

2013-05-06T23:59:59.000Z

Note: This page contains sample records for the topic "graphi te hoback" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

CdTe and Cd0.9Zn0.1Te Crystal Growth and Characterization for Nuclear Spectrometers  

Science Conference Proceedings (OSTI)

Large volume single crystals of CdTe and Cd0.9Zn0.1Te (CZT) have been grown by a controlled vertical Bridgman technique using in-house zone refined precursors and characterized through structural, electrical, optical, and spectroscopic methods. The grown crystals (diameter greater than or equal to 2.5 cm and length >10 cm) have shown promising characteristics for high-resolution room temperature solid-state radiation detectors due to their high resistivity (~1010 -cm for CdTe, and >1011 -cm for CZT) and good charge transport properties [ e ~ (2-5)x10-3 cm2/V]. The fabricated detectors in planar single element and Frisch collar configurations have shown very low leakage currents and high count rates for various sources, including Am-241, and Cs-137. The grown crystals have been further characterized by X-ray diffraction (XRD), infrared spectroscopy (IR), and transmission two-modulator generalized ellipsometry (2-MGE). Details of the CdTe and CZT characterization results, detector fabrication steps, and testing with radiation sources are presented. The CdTe and CZT crystals have shown high prospects for low power rating solid-state nuclear spectrometers and medical imaging devices.

Mandal, Krishna [EIC Laboratories, Inc.; Kang, Sung Hoon [EIC Laboratories, Inc.; Choi, Michael [EIC Laboratories, Inc.; Wright, Gomez W [ORNL; Jellison Jr, Gerald Earle [ORNL

2006-01-01T23:59:59.000Z

62

A 3 TeV Muon Collider Lattice Design  

SciTech Connect

A new lattice for 3 TeV c.o.m. energy with {beta}* = 5mm was developed which follows the basic concept of the earlier 1.5 TeV design but uses quad triplets for the final focus in order to keep the maximum magnet strength and aperture close to those in 1.5 TeV case. Another difference is employment of combined-function magnets with the goal to lower heat deposition in magnet cold mass and to eliminate bending field free regions which produce 'hot spots' of neutrino radiation that can be an issue at higher energy. The proposed lattice is shown to satisfy the requirements on luminosity, dynamic aperture and momentum acceptance.

Alexahin, Y.; Gianfelice-Wendt, E.; /Fermilab

2012-05-01T23:59:59.000Z

63

Junction Evolution During Fabrication of CdS/CdTe Thin-film PV Solar Cells (Presentation)  

DOE Green Energy (OSTI)

Discussion of the formation of CdTe thin-film PV junctions and optimization of CdTe thin-film PV solar cells.

Gessert, T. A.

2010-09-01T23:59:59.000Z

64

Feasibility of GRB with TeV gamma ray all sky monitor  

E-Print Network (OSTI)

We discuss feasibility of Gamma ray burst (GRB) with TeV gamma ray all sky monitor and discuss necessity of TeV gamma ray cherenkov all sky monitor.

S. Osone

2003-05-14T23:59:59.000Z

65

V-183: Cisco TelePresence TC and TE Bugs Let Remote Users Deny...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

3: Cisco TelePresence TC and TE Bugs Let Remote Users Deny Service and Remote Adjacent Authenticated Users Gain Root Shell Access V-183: Cisco TelePresence TC and TE Bugs Let...

66

Electrophysical properties of semimagnetic solid solutions Hg 1?x Mn x Te  

Science Conference Proceedings (OSTI)

A comprehensive study of the electrophysical properties of the semimagnetic ternary solid solution Hg 1?x Mn x Te an alternative material to Hg 1?x Cd x Te is reported. The charge-carrier scattering

I. M. Nesmelova; V. N. Ryzhkov; M. I. Ibragimova; V. Yu. PetukhovKazan Physicotechnical Institute, Kazan Research Center of the Russian Academy of Sciences, Kazan?420029, Russia

2004-01-01T23:59:59.000Z

67

Micro-PL Studies of Polycrustalline CdS/CdTe Interfaces  

DOE Green Energy (OSTI)

We describe a technique of photoluminescence measurements with a resolutiion of microns. This technique is applied to examine the CdS/CdTe interface of CdTe solar cells.

Dhere, R.; Cheong, M.; Smith, S.; Albin, D.; Mascarenhas, A.; Gessert, T. A.

2000-01-01T23:59:59.000Z

68

High contrast, CdTe portal scanner for radiation therapy  

Science Conference Proceedings (OSTI)

This paper reports on one of the most promising new technologies for improving the qualify of radiation therapy, the use of real-time systems to produce portal images. In the authors' approach, they are constructing a linear array of 256 CdTe photovoltaic detectors attached to a very compact linear scanner, all of which will be mounted in a cassette shaped package to be located under the patient table. The high stopping power of the CdTe allows a high contrast image to be made using only a single Linac pulse per line, resulting in a high contrast image in under 5 seconds.

Entine, G.; Squillante, M.R.; Hahn, R.; Cirignano, L.J.; McGann, W. (Radiation Monitoring Devices, Inc., Watertown, MA (United States)); Biggs, P.J. (Massachusetts General Hospital, Boston, MA (United States))

1992-10-01T23:59:59.000Z

69

JUN TION SOLAR ELLS TE HNOLOGY READINESS LEVEL: 5 US PATENT ...  

POTENTIAL APPLI ATIONS TE HNOLOGI AL Generation of electricity for space photovoltaic applications Terrestrial high-concentration photovoltaic applications

70

TOP AT FOR THE ALIGNMENT & ON ENTRATION OF SOLAR TROUGHS TE ...  

POTENTIAL APPLI ATIONS Clean energy production Electric Utility Alternative energy options TE HNOLOGI AL ENEFITS Simple & easy to implement

71

Formation of ZnTe:Cu/Ti Contacts at High Temperature for CdS/CdTe Devices (Presentation)  

DOE Green Energy (OSTI)

The conclusions of this report are that Cu diffusion from a ZnTe:Cu contact causes good and bad things. The good (Cu in CdS < low 10{sup 18} cm{sup -3})--increase in CdTe N{sub A}-N{sub D} that leads to V{sub oc} and FF improvement. The bad (Cu in CdS > low 10{sup 18} cm{sup -3})--(1) possibly decreased of shunt resistance (?); (2) depletion width in CdTe can become too narrow for optimum current collection at J{sub MPP}; (3) donor reduction in CdS (significant FF loss in LIV); and (4) excessive Cu diffusion into CdS readily observed by red-light bias QE.

Gessert, T. A.; Asher, S.; Johnston, S.; Duda, A.; Young, M. R.; Moriarty, T.

2006-05-01T23:59:59.000Z

72

Appendix B: CArBon dioxide CApture teChnology SheetS  

NLE Websites -- All DOE Office Websites (Extended Search)

DioxiDe CaPture teChnology sheets national energy teChnology laboratory aDvanCeD aCiD gas seParation teChnology for the utilization of low-rank Coals primary project goals Air...

73

Detector Performance of Ammonium-Sulfide-Passivated CdZnTe and CdMnTe Materials  

Science Conference Proceedings (OSTI)

Dark currents, including those in the surface and bulk, are the leading source of electronic noise in X-ray and gamma detectors, and are responsible for degrading a detector's energy resolution. The detector material itself determines the bulk leakage current; however, the surface leakage current is controllable by depositing appropriate passivation layers. In previous research, we demonstrated the effectiveness of surface passivation in CZT (CdZnTe) and CMT (CdMnTe) materials using ammonium sulfide and ammonium fluoride. In this research, we measured the effect of such passivation on the surface states of these materials, and on the performances of detectors made from them.

Kim, K.H.; Bolotnikov, A.E.; Camarda, G.S.; Marchini, L.; Yang, G.; Hossain, A.; Cui, Y.; Xu, L.; and James, R.B.

2010-08-01T23:59:59.000Z

74

School of Mathematical and Computing Sciences Te Kura Pangarau, Rorohiko  

E-Print Network (OSTI)

#12;School of Mathematical and Computing Sciences Te Kura Pangarau, Rorohiko Vortex geometry constant throughout the fluid flow. The velocity of the fluid flow is v = (A ^r + B ^) r . Use constant throughout the fluid flow. The velocity of the fluid flow is v = (A ^r + B ^) r . Streamlines are equiangular

Visser, Matt

75

The TeV spectrum of H1426+428  

E-Print Network (OSTI)

The BL Lac object H1426+428 was recently detected as a high energy gamma-ray source by the VERITAS collaboration (Horan et al. 2002). We have reanalyzed the 2001 portion of the data used in the detection in order to examine the spectrum of H1426+428 above 250 GeV. We find that the time-averaged spectrum agrees with a power law of the shape dF/dE = 10^(-7.31 +- 0.15(stat) +- 0.16(syst)) x E^(-3.50 +- 0.35(stat) +- 0.05(syst)) m^(-2)s^(-1)TeV^(-1) The statistical evidence from our data for emission above 2.5 TeV is 2.6 sigma. With 95% c.l., the integral flux of H1426+428 above 2.5 TeV is larger than 3% of the corresponding flux from the Crab Nebula. The spectrum is consistent with the (non-contemporaneous) measurement by Aharonian et al. (2002) both in shape and in normalization. Below 800 GeV, the data clearly favours a spectrum steeper than that of any other TeV Blazar observed so far indicating a difference in the processes involved either at the source or in the intervening space.

D. Petry; I. H. Bond; S. M. Bradbury; J. H. Buckley; D. A. Carter-Lewis; W. Cui; C. Duke; I. de la Calle Perez; A. Falcone; D. J. Fegan; S. J. Fegan; J. P. Finley; J. A. Gaidos; K. Gibbs; S. Gammell; J. Hall; T. A. Hall; A. M. Hillas; J. Holder; D. Horan; M. Jordan; M. Kertzman; D. Kieda; J. Kildea; J. Knapp; K. Kosack; F. Krennrich; S. LeBohec; P. Moriarty; D. Mller; T. N. Nagai; R. Ong; M. Page; R. Pallassini; B. Power-Mooney; J. Quinn; N. W. Reay; P. T. Reynolds; H. J. Rose; M. Schroedter; G. H. Sembroski; R. Sidwell; N. Stanton; S. P. Swordy; V. V. Vassiliev; S. P. Wakely; G. Walker; T. C. Weekes

2002-07-23T23:59:59.000Z

76

TeV Dark Matter detection by Atmospheric Cerenkov Telescopes  

E-Print Network (OSTI)

Ground based Atmospheric Cerenkov Telescopes have recently unveiled a TeV gamma-ray signal from the direction of the Galactic Centre. We examine whether these gamma-rays, observed by the VERITAS, CANGAROO-II and HESS collaborations, may arise from annihilations of dark matter particles. Emission from nearby dwarf spheroidals, such as Sagittarius, could provide a test of this scenario.

Francesc Ferrer

2005-05-19T23:59:59.000Z

77

Diffuse TeV Emission at the Galactic Centre  

E-Print Network (OSTI)

The High-Energy Stereoscopic System (HESS) has detected intense diffuse TeV emission correlated with the distribution of molecular gas along the galactic ridge at the centre of our Galaxy. Earlier HESS observations of this region had already revealed the presence of several point sources at these energies, one of them (HESS J1745-290) coincident with the supermassive black hole Sagittarius A*. It is still not entirely clear what the origin of the TeV emission is, nor even whether it is due to hadronic or leptonic interactions. It is reasonable to suppose, however, that at least for the diffuse emission, the tight correlation of the intensity distribution with the molecular gas indicates a pionic-decay process involving relativistic protons. In this paper, we explore the possible source(s) of energetic hadrons at the galactic centre, and their propagation through a turbulent medium. We conclude that though Sagittarius A* itself may be the source of cosmic rays producing the emission in HESS J1745-290, it cannot be responsible for the diffuse emission farther out. A distribution of point sources, such as pulsar wind nebulae dispersed along the galactic plane, similarly do not produce a TeV emission profile consistent with the HESS map. We conclude that only a relativistic proton distribution accelerated throughout the inter-cloud medium can account for the TeV emission profile measured with HESS.

Elizabeth Wommer; Fulvio Melia; Marco Fatuzzo

2008-04-18T23:59:59.000Z

78

Carrier dynamics and activation energy of CdTe quantum dots in a Cd{sub x}Zn{sub 1-x}Te quantum well  

SciTech Connect

We investigate the optical properties of CdTe quantum dots (QDs) in a Cd{sub 0.3}Zn{sub 0.7}Te quantum well (QW) grown on GaAs (100) substrates. Carrier dynamics of CdTe/ZnTe QDs and quantum dots-in-a-well (DWELL) structure is studied using time-resolved photoluminescence (PL) measurements, which show the longer exciton lifetime of the DWELL structure. The activation energy of the electrons confined in the DWELL structure, as obtained from the temperature-dependent PL spectra, was also higher than that of electrons confined in the CdTe/ZnTe QDs. This behavior is attributed to the better capture of carriers into QDs within the surrounding QW.

Han, W. I.; Lee, J. H.; Yu, J. S.; Choi, J. C. [Department of Physics, Yonsei University, Wonju 220-710 (Korea, Republic of); Lee, H. S. [Advanced Photonics Research Institute, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of)

2011-12-05T23:59:59.000Z

79

A Note on TeV Cerenkov Events as Bose-Einstein Gamma Condensations  

E-Print Network (OSTI)

The idea that the TeV air showers, thought to be produced by >10 TeV gamma rays from Mrk 501, can be mimicked by coherent bunches of sub-TeV photons is reexamined, focusing on fundamental considerations. In particular, it is shown that the minimum spot size of the beam of pulsed TeV photons arriving at Earth is on the order of a few kilometers, unless a lens with certain characteristics is placed between the TeV laser and Earth. The viability of the laser production mechanism proposed by Harwit et al. (2000) is also reassessed.

Amir Levinson

2000-07-09T23:59:59.000Z

80

Novel ways of depositing ZnTe films by a solution growth technique  

DOE Green Energy (OSTI)

An electrochemical process has been successfully developed for the reproducible deposition of ZnTe and copper-doped ZnTe films suitable as transparent ohmic contacts for CdS/CdTe solar cells. The development of this method and optimization of key processing steps in the fabrication of CdS/CdTe/ZnTe:Cu devices has allowed IEC to achieve cell performance results of FF>70% and {eta} {approximately}10%. Preliminary efforts have indicated that the deposition methods investigated are potentially feasible for the formation of other II-VI compounds for use in polycrystalline thin film solar devices and should be the focus of future work.

Birkmire, R.W.; McCandless, B.E.; Yokimcus, T.A.; Mondal, A. (Delaware Univ., Newark, DE (United States). Inst. of Energy Conversion)

1992-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "graphi te hoback" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Contributions to 2^nd TeV Particle Astrophysics Conference (TeV PA II) Madison Wisconsin - 28-31 August 2006  

E-Print Network (OSTI)

This collection of proceedings to the TeV PA II Conference presents some of the latest results of the IceCube Collaboration.

IceCube Collaboration; A. Achterberg

2006-11-18T23:59:59.000Z

82

Comparison of CdTe and CdZnTe Detectors for Field Determination of Uranium Isotopic Enrichments  

DOE Green Energy (OSTI)

A performance comparison of a CdTe and a CdZnTe detector when exposed to uranium samples of various isotopic enrichments has been performed. These high-resolution detectors can assist in the rapid determination of uranium isotopic content of illicit material. Spectra were recorded from these room temperature semiconductor detectors with a portable multi-channel analyzer, both in the laboratory and in a field environment. Both detectors were operated below ambient temperature using the vendor supplied thermoelectric coolers. Both detectors had nominally the same active volume (18 mm3 for the CdZnTe and 25 mm3 for the CdTe detector) and resolution. Spectra of samples of known isotopic content were recorded at fixed geometries. An evaluation of potential signature g rays for the detection of enriched uranium was completed. Operational advantages and disadvantages of each detector are discussed. There is a need to improve the detection sensitivity during the interdiction of special nuclear materials (SNM) for increased homeland protection. It is essential to provide additional tools to first responders and law enforcement personnel for assessing nuclear and radiological threats.

Hofstetter, KJ

2004-01-23T23:59:59.000Z

83

Enhancement of the steady state minority carrier lifetime in HgCdTe photodiode using ECR plasma hydrogenation  

Science Conference Proceedings (OSTI)

Keywords: HgCdTe, diffusion length, field effect transistor, hydrogenation, lifetime, mobility, photodiode

Han Jung; Hee Chul Lee; Choong-Ki Kim

1996-08-01T23:59:59.000Z

84

MHK Projects/TE4 | Open Energy Information  

Open Energy Info (EERE)

TE4 TE4 < MHK Projects Jump to: navigation, search << Return to the MHK database homepage Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":5,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"500px","height":"350px","centre":false,"title":"","label":"","icon":"File:Aquamarine-marker.png","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":52.3247,"lon":1.68765,"alt":0,"address":"","icon":"http:\/\/prod-http-80-800498448.us-east-1.elb.amazonaws.com\/w\/images\/7\/74\/Aquamarine-marker.png","group":"","inlineLabel":"","visitedicon":""}]}

85

TeV scale dark matter and electroweak radiative corrections  

SciTech Connect

Recent anomalies in cosmic rays data, namely, from the PAMELA Collaboration, can be interpreted in terms of TeV scale decaying/annihilating dark matter. We analyze the impact of radiative corrections coming from the electroweak sector of the standard model on the spectrum of the final products at the interaction point. As an example, we consider virtual one loop corrections and real gauge bosons emission in the case of a very heavy vector boson annihilating into fermions. We find electroweak corrections that are relevant, but not as big as sometimes found in the literature; we relate this mismatch to the issue of gauge invariance. At scales much higher than the symmetry breaking scale, one loop electroweak effects are so big that eventually higher orders/resummations have to be considered: we advocate for the inclusion of these effects in parton shower Monte Carlo models aiming at the description of TeV scale physics.

Ciafaloni, Paolo; Urbano, Alfredo [INFN - Sezione di Lecce and Universita del Salento, Via per Arnesano, I-73100 Lecce (Italy)

2010-08-15T23:59:59.000Z

86

High-efficiency large-area CdTe panels  

DOE Green Energy (OSTI)

The objective of this three year effort has been to develop an improved materials technology and fabrication process for limited volume production of 1 ft{sup 2} and 4 ft{sup 2} CdS/CdTe photovoltaic modules. The module stability objective by the end of this three year subcontract was to develop techniques to provide ten year life exploration with no greater than 10% degradation. In order to achieve these efficiency and stability objectives, the research program has been separated into tasks including: (1) analysis and characterization of CdS/CdTe Devices; (2) performance optimization on small cells; (3) encapsulation and stability testing; and (4) module efficiency optimization. 27 refs., 18 figs., 3 tabs.

Albright, S.P.; Chamberlin, R.R.; Jordan, J.F. (Photon Energy, Inc., El Paso, TX (USA))

1990-11-01T23:59:59.000Z

87

Charge transport properties of CdMnTe radiation detectors  

Science Conference Proceedings (OSTI)

Growth, fabrication and characterization of indium-doped cadmium manganese telluride (CdMnTe)radiation detectors have been described. Alpha-particle spectroscopy measurements and time resolved current transient measurements have yielded an average charge collection efficiency approaching 100 %. Spatially resolved charge collection efficiency maps have been produced for a range of detector bias voltages. Inhomogeneities in the charge transport of the CdMnTe crystals have been associated with chains of tellurium inclusions within the detector bulk. Further, it has been shown that the role of tellurium inclusions in degrading chargecollection is reduced with increasing values of bias voltage. The electron transit time was determined from time of flight measurements. From the dependence of drift velocity on applied electric field the electron mobility was found to be n = (718 55) cm2/Vs at room temperature.

Kim K.; Rafiel, R.; Boardman, M.; Reinhard, I.; Sarbutt, A.; Watt, G.; Watt, C.; Uxa, S.; Prokopovich, D.A.; Belas, E.; Bolotnikov, A.E.; James, R.B.

2012-04-11T23:59:59.000Z

88

Sub-barrier fusion enhancement with radioactive 134Te  

E-Print Network (OSTI)

The fusion cross sections of radioactive $^{134}$Te + $^{40}$Ca were measured at energies above and below the Coulomb barrier. The evaporation residues produced in the reaction were detected in a zero-degree ionization chamber providing high efficiency for inverse kinematics. Both coupled-channel calculations and comparison with similar Sn+Ca systems indicate an increased sub-barrier fusion probability that is correlated with the presence of positive Q-value neutron transfer channels. In comparison, the measured fusion excitation functions of $^{130}$Te + $^{58,64}$Ni, which have positive Q-value neutron transfer channels, were accurately reproduced by coupled-channel calculations including only inelastic excitations. The results demonstrate that the coupling of transfer channels can lead to enhanced sub-barrier fusion but this is not directly correlated with positive Q-value neutron transfer channels in all cases.

Z. Kohley; J. F. Liang; D. Shapira; C. J. Gross; R. L. Varner; J. M. Allmond; J. J. Kolata; P. E. Mueller; A. Roberts

2013-06-28T23:59:59.000Z

89

Sub-barrier fusion enhancement with radioactive 134Te  

Science Conference Proceedings (OSTI)

The fusion cross sections of radioactive 134Te + 40Ca were measured at energies above and below the Coulomb barrier. The evaporation residues produced in the reaction were detected in a zero-degree ionization chamber providing high efficiency for inverse kinematics. Both coupled-channel calculations and comparison with similar Sn + Ca systems indicate an increased sub-barrier fusion probability that is correlated with the presence of positive Q-value neutron transfer channels. In comparison, the measured fusion excitation functions of 130Te + 58,64Ni, which have positive Q-value neutron transfer channels, were accurately reproduced by coupled-channel calculations including only inelastic excitations. The results demonstrate that the coupling of transfer channels can lead to enhanced sub-barrier fusion but this is not directly correlated with positive Q-value neutron transfer channels in all cases.

Kohley, Zachary W [ORNL; Liang, J Felix [ORNL; Shapira, Dan [ORNL; Gross, Carl J [ORNL; Varner Jr, Robert L [ORNL; Allmond, James M [ORNL; Kolata, Jim J [University of Notre Dame, IN; Mueller, Paul Edward [ORNL; Roberts, Amy [University of Notre Dame, IN

2013-01-01T23:59:59.000Z

90

Formation and Characterization of CdSxTe1-x Alloys Prepared from Thin Film Couples of CdS and CdTe: Preprint  

DOE Green Energy (OSTI)

This conference paper describes the alloying between CdS and CdTe at the CdS/CdTe interface is a function of the growth temperature and post-deposition CdCl2 heat treatment (HT). In devices prepared by different techniques, Te-rich CdSxTe1-x alloys with x= 0.04 to 0.08 have been identified. We present our work on thin-film couples of CdS and CdTe, which can withstand higher level of CdCl2 treatment without the adhesion problems typically encountered in the regular device structure. CdS films with a thickness of {approx}100 nm were deposited by chemical-bath deposition on glass/SnO2 substrates, and CdTe films with a thickness of 300 and 800 nm were deposited by close-spaced sublimation. The samples were treated in the presence of vapor CdCl2 at 400-450 C for 5 min. X-ray diffraction and optical analysis of the samples showed that S content in the CdSxTe1-x alloy increased systematically with the CdCl2 HT temperature. CdSxTe1-x alloy with x= 0.14 was identified for the samples treated at 4 30C, which is much higher than expected from the miscibility gap at 430C.

Dhere, R.; Wu, X.; Albin, D.; Perkins, C.; Moutinho, H.; Gessert, T.

2002-05-01T23:59:59.000Z

91

Mr. John E. Kieling, Chief Hazardous Was te Bureau  

NLE Websites -- All DOE Office Websites (Extended Search)

John E. Kieling, Chief John E. Kieling, Chief Hazardous Was te Bureau Depa rtment of Energy Carlsbad Field Office P. O. Box 3090 Carlsbad , New Mexico 88221 NOV 0 5 2013 New Mexico Environment Department 2905 Rodeo Park Drive East. Building 1 Santa Fe, New Mexico 87505-6303 Subject: Panel 6 Closure and Final Waste Emplacement Notifications Dear Mr. Kieling : The purpose of this leiter is 1 0 notify th e New Mexico Environment Department (NMEO) that the

92

Flat beams in a 50 TeV hadron collider  

SciTech Connect

The basic beam dynamics of a next generation 50 x 50 TeV hadron collider based on a high field magnet approach have been outlined over the past several years. Radiation damping not only produces small emittances, but also flat beams, just as in electron machines. Based on {open_quotes}Snowmass 96{close_quotes} parameters, we investigate the issues associated with flat beams in very high energy hadron colliders.

Peggs, S.; Harrison, M.; Pilat, F.; Syphers, M.

1997-08-01T23:59:59.000Z

93

ELUTIONS Inc formerly TeCom | Open Energy Information  

Open Energy Info (EERE)

ELUTIONS Inc formerly TeCom ELUTIONS Inc formerly TeCom Jump to: navigation, search Name ELUTIONS Inc (formerly TeCom) Place Tampa, Florida Zip 33605 Sector Efficiency Product Tampa-based wireless enterprise automation solutions firm. Elutions provides an Active Energy Management service allowing users to increase efficiency by monitoring, forecasting and analyzing utility resource consumption. Coordinates 27.94653°, -82.459269° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":27.94653,"lon":-82.459269,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

94

Development of ZnTe:Cu Contacts for CdTe Solar Cells: Cooperative Research and Development Final Report, CRADA Number CRD-08-320  

DOE Green Energy (OSTI)

The main focus of the work at NREL was on the development of Cu-doped ZnTe contacts to CdTe solar cells in the substrate configuration. The work performed under the CRADA utilized the substrate device structure used at NREL previously. All fabrication was performed at NREL. We worked on the development of Cu-doped ZnTe as well as variety of other contacts such as Sb-doped ZnTe, CuxTe, and MoSe2. We were able to optimize the contacts to improve device parameters. The improvement was obtained primarily through increasing the open-circuit voltage, to values as high as 760 mV, leading to device efficiencies of 7%.

Dhere, R.

2012-04-01T23:59:59.000Z

95

Bismuth-induced deep levels and carrier compensation in CdTe  

Science Conference Proceedings (OSTI)

First-principles calculations show that Bi on Cd site in CdTe can be either a donor, Bi_Cd+, or an acceptor, Bi_Cd- , depending on the Fermi level. The can bind a substitutional O (O_Te) with large binding energy of 1.40 eV. The calculated (0/-) transition level for B_Cd- - O_Te complex is in good agreement with the observed deep hole trapping level. Bi can also substitute Te to form an acceptor. The amphoteric nature of Bi in CdTe results in the pinning of the Fermi level and the high resistivity. We also discuss the origin of p-type CdTe at high Bi doping level.

Du, Mao-Hua [ORNL

2008-01-01T23:59:59.000Z

96

The Effect of Structural Vacancies on the Thermoelectric Properties of (Cu2Te)1-x(Ga2Te3)x  

SciTech Connect

We have studied the effects of structural vacancies on the thermoelectric properties of the ternary compounds (Cu2Te)1-x(Ga2Te3)x (x = 0.5, 0.55, 0.571, 0.6, 0.625, 0.667 and 0.75), which are solid solutions found in the pseudo-binary phase diagram for Cu2Te and Ga2Te3. This system possesses tunable structural vacancy concentrations. The x= 0.5 phase, CuGaTe2, is nominally devoid of structural vacancies, while the rest of the compounds contain varying amounts of these features, and the volume density of vacancies increases with Ga2Te3 content. The sample with x = 0.5, 0.55, 0.571, 0.6, 0.625 crystallize in the chalcopyrite structure while the x = 0.667 and 0.75 adopt the Ga2Te3 defect zinc blende structure. Strong scattering of heat carrying phonons by structural defects, leads to the reduction of thermal conductivity, which is beneficial to the thermoelectric performance of materials. On the other hand, these defects also scatter charge carriers and reduce the electrical conductivity. All the samples investigated are p-type semiconductors as inferred by the signs of their respective Hall (RH) and Seebeck (S) coefficients. The structural vacancies were found to scatter phonons strongly, while a combination of increased carrier concentration, and vacancies decreases the Hall mobility ( H), degrading the overall thermoelectric performance. The room temperature H drops from 90 cm2/V s for CuGaTe2 to 13 cm2/V s in Cu9Ga11Te21 and 4.6 cm2/V s in CuGa3Te5. The low temperature thermal conductivity decreases significantly with higher Ga2Te3 concentrations (higher vacancy concentration) due to increased point defect scattering which dominate thermal resistance terms. At high temperatures, the dependence of thermal conductivity on the Ga2Te3 content is less significant. The presence of strong Umklapp scattering leads to low thermal conductivity at high temperatures for all samples investigated. The highest ZT among the samples in this study was found for the defect-free CuGaTe2 with ZT ~ 1.0 at 840K.

Ye, Zuxin [GM Research and Development Center; Cho, Jung Y [GM R& D and Planning, Warren, Michigan; Tessema, Misle [GM Research and Development Center; Salvador, James R. [GM R& D and Planning, Warren, Michigan; Waldo, Richard [GM R& D and Planning, Warren, Michigan; Wang, Hsin [ORNL; Cai, Wei [ORNL

2013-01-01T23:59:59.000Z

97

High Efficiency Single Crystal CdTe Solar Cells: November 19, 2009 - January 31, 2011  

DOE Green Energy (OSTI)

The goal of the program was to develop single crystal CdTe-based top cells grown on Si solar cells as a platform for the subsequent manufacture of high efficiency tandem cells for CPV applications. The keys to both the single junction and the tandem junction cell architectures are the ability to grow high quality single-crystal CdTe and CdZnTe layers on p-type Si substrates, to dope the CdTe and CdZnTe controllably, both n and p-type, and to make low resistance ohmic front and back contacts. EPIR demonstrated the consistent MBE growth of CdTe/Si and CdZnTe/Si having high crystalline quality despite very large lattice mismatches; epitaxial CdTe/Si and CdZnTe/Si consistently showed state-of-the-art electron mobilities and good hole mobilities; bulk minority carrier recombination lifetimes of unintentionally p-doped CdTe and CdZnTe grown by MBE on Si were demonstrated to be consistently of order 100 ns or longer; desired n- and p-doping levels were achieved; solar cell series specific resistances <10 ?-cm2 were achieved; A single-junction solar cell having a state-of-the-art value of Voc and a unverified 16.4% efficiency was fabricated from CdZnTe having a 1.80 eV bandgap, ideal for the top junction in a tandem cell with a Si bottom junction.

Carmody, M.; Gilmore, A.

2011-05-01T23:59:59.000Z

98

Novel CdTe Cell Fabrication Process with Potential for Low Cost and High Throughput  

DOE Green Energy (OSTI)

There are several production disadvantages inherent in the conventional SnO(2)/CdS/CdTe manufacturing processes. In this paper, we report a novel manufacturing process for fabrication of polycrystalline Cd(2)SnO(4)/Zn(2)/SnO(4)/CdS/CdTe thin-film solar cells that yielded a CdS/CdTe device with an NREL-confirmed efficiency of 14.0%.

Wu, X.; Sheldon, P.

2000-01-01T23:59:59.000Z

99

Electrical properties of PbTe single crystals with excess tellurium  

Science Conference Proceedings (OSTI)

The effects of excess (up to 0.1 at %) Te atoms and heat treatment at 473 and 573 K for 120 h on the conductivity {sigma}, thermopower {alpha}, and Hall coefficient R of PbTe single crystals are studied. It is shown that excess Te atoms and annealing strongly affect the values and character of the temperature dependences of these parameters and the signs of {alpha} and R at low temperatures, which is caused by the acceptor effect of these atoms and the formation of antisite defects due to localization of Te in vacancies of the lead sublattice upon annealing.

Bagiyeva, G. Z., E-mail: bagieva-gjulandam@rambler.ru; Mustafayev, N. B.; Abdinova, G. Dj.; Abdinov, D. Sh. [National Academy of Sciences of Azerbaijan, Abdullaev Institute of Physics (Azerbaijan)

2011-11-15T23:59:59.000Z

100

Simulated Performance of the GammaTracker CdZnTe Handheld ...  

Simulated Performance of the GammaTracker CdZnTe Handheld Radioisotope Identifier Carolyn E. Seifert, Member, IEEE, Mitchell J. Myjak, Member, IEEE, ...

Note: This page contains sample records for the topic "graphi te hoback" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Mechanical Properties of Thermoelectric Materials PbTe-PbS and ...  

Science Conference Proceedings (OSTI)

... thermoelectric (TE) materials for a variety of applications, including the conversion of waste heat energy into electricity. LAST (Lead-Antimony-Silver-

102

Electrodeposition of PbTe Thermoelectric Materials in NaOH Solutions  

Science Conference Proceedings (OSTI)

Dissolution Kinetics of Steelmaking Slag and Its Promotion for the Growth of Algae Electrodeposition of PbTe Thermoelectric Materials in NaOH Solutions.

103

Characterization and Analysis of CIGS and CdTE Solar Cells: December 2004 - July 2008  

DOE Green Energy (OSTI)

The work reported here embodies a device-physics approach based on careful measurement and interpretation of data from CIGS and CdTe solar cells.

Sites, J. R.

2009-01-01T23:59:59.000Z

104

NREL Determines Long-Lived Carriers and Differences in CdTe Superstrat...  

NLE Websites -- All DOE Office Websites (Extended Search)

"Comparison of Minority Carrier Lifetime Measurements in Superstrate and Substrate CdTe PV Devices." Proc. 37 th IEEE Photovoltaic Specialists Conference, 19-24 June 2011,...

105

Review of Photovoltaic Energy Production Using CdTe Thin-Film Modules: Extended Abstract Preprint  

DOE Green Energy (OSTI)

CdTe has near-optimum bandgap, excellent deposition traits, and leads other technologies in commercial PV module production volume. Better understanding materials properties will accelerate deployment.

Gessert, T. A.

2008-09-01T23:59:59.000Z

106

Characterization of Heterogeneities in Detector-Grade CdZnTe Crystals  

Science Conference Proceedings (OSTI)

Synthetic Cd{sub 1-x}ZnxTe or 'CZT' crystals are highly suitable for g-spectrometers operating at room temperature. Secondary phases (SP) within CZT, presumed to be Te metal, have detrimental impacts on the charge collection efficiency of fabricated device. Using analytical techniques rather than arbitrary theoretical definitions, we identify two SP morphologies: (i) many void, 20-{mu}m 'negative' crystals with 65-nm nanoparticle residues of Si, Cd, Zn, and Te and (ii) 20-{mu}m hexagonal-shaped bodies, which are composites of metallic Te layers with cores of amorphous and polycrystalline CZT material that surround the voids.

Duff, M.; Hunter, D; Burger, A; Groza, M; Buliga, V; Bradley, J; Graham, G; Dai, Z; Lanzirotti, A; et. al.

2009-01-01T23:59:59.000Z

107

~~~~: Gmt Lakes Cat-bar) ALTERNaTE I  

Office of Legacy Management (LM)

~~~: Gmt Lakes Cat-bar) ~~~: Gmt Lakes Cat-bar) ALTERNaTE I --------------------------------------- NAME: 333 Iv. Mkhi qr) Aw. thka o ~~~---~~~--~~~_-----__ C I TV : 8 Morim 'Love 82 10 bhh &Q Ir -+----------- STATE- fL I - ------ l OWNER(S) -__----_ past: Current: I --------------------____ Owner contacted q yes p no; _____--_____-____------~~~l if yes, data contacted -_--------__- TYPE OF OPERATION ---_------------- 0 Research & Development q Production scale testing 0 Pilot Scale 0 Bench Scale process 0 Theoretical Studies 0 Sample & Analysis Facility Type p Manufacturing I ! fJ University 0 Research Organization ! 0 Government Sponsored F+ci li ty 0 Other ----~~-~~~----~------ 0 Production 0 Disposal/Storage TYPE OF CUNTRKT ----~---~__----_ / w Prime

108

Multiple charge density wave transitions in Gd2Te5  

Science Conference Proceedings (OSTI)

Diffraction measurements performed via transmission electron microscopy and high resolution X-ray scattering reveal two distinct charge density wave transitions in Gd{sub 2}Te{sub 5} at T{sub c1} = 410(3) and T{sub c2} = 532(3) K, associated with the on-axis incommensurate lattice modulation and off-axis commensurate lattice modulation respectively. Analysis of the temperature dependence of the order parameters indicates a non-vanishing coupling between these two distinct CDW states.

Shin, K.Y.; Ru, N.; /Stanford U., Geballe Lab. /Stanford U., Appl. Phys. Dept.; Condron, C.L.; /SLAC, SSRL; Wu, Y.Q.; Kramer, M.J.; Toney, M.F.; /Ames Lab /Iowa State U., Dept. Mater. Sci. /SLAC, SSRL; Fisher, I.R.; /Stanford U., Geballe Lab. /Stanford U., Appl. Phys. Dept.

2010-02-15T23:59:59.000Z

109

Conformal and projection diagrams in LaTeX  

E-Print Network (OSTI)

In general relativity, the causal structure of space-time may sometimes be depicted by conformal Carter-Penrose diagrams or a recent extension of these - the projection diagrams. The introduction of conformal diagrams in the sixties was one of the progenitors of the golden age of relativity. They are the key ingredient of many scientific papers. Unfortunately, drawing them in the form suitable for LaTeX documents is time-consuming and not easy. We present below a library that allows one to draw an arbitrary conformal diagram in a few simple steps.

Christa R. lz; Sebastian J. Szybka

2013-05-09T23:59:59.000Z

110

Fabrication and Physics of CdTe Devices by Sputtering: Final Report, 1 March 2005 - 30 November 2008  

DOE Green Energy (OSTI)

Work to understand CdS/CdTe solar cell device physics; increase magnetron sputtering rate (while keeping high device quality); reduce thickness of CdTe layers (while keeping voltage and fill factor).

Compaan, A.; Collins, R.; Karpov, V.; Giolando, D.

2009-04-01T23:59:59.000Z

111

Distributed fault management in WBEM-Based Inter-AS TE for qos guaranteed DiffServ-overMPLS  

Science Conference Proceedings (OSTI)

Distributed fault management and event notification are essential in Inter-AS Traffic Engineering (TE). In this paper we design and implement distributed fault management for WBEM based inter-AS TE. We designed DMTF Managed Object Format (MOF) based ...

Abdurakhmon Abdurakhmanov; Shahnaza Tursunova; Shanmugham Sundaram; Young-Tak Kim

2006-09-01T23:59:59.000Z

112

A Search for TeV Emission from Active Galaxies using the Milagro Observatory  

E-Print Network (OSTI)

: Professor Gregory W. Sullivan, Chairman/Advisor Professor Jordan A. Goodman Professor Rabindra N. Mohapatra that observes very high energy gamma rays (100 GeV to 100 TeV) using the water-Cerenkov techniqueV candidates. Active galaxies have been observed to be highly variable at TeV energies. To test for episodic

California at Santa Cruz, University of

113

Search for Short Duration Bursts of TeV Gamma Rays with the Milagrito Telescope  

E-Print Network (OSTI)

OG 2.3.07 Search for Short Duration Bursts of TeV Gamma Rays with the Milagrito Telescope Gus for short duration bursts of TeV photons. Such bursts may result from "traditional" gamma-ray bursts to gamma-ray bursts, the final stages of black hole evaporation) the most compelling reason may

California at Santa Cruz, University of

114

Charge transport in mixed CdSe and CdTe colloidal nanocrystal films  

E-Print Network (OSTI)

We report the influence of trap states on charge transport through films of mixed CdTe and CdSe nanocrystals (NCs) between lateral electrodes, through layered films of CdTe and CdSe NCs in a layered geometry, and through ...

Bawendi, Moungi G.

115

Effects of Surface Composition on CdTe/CdS Device Performance  

DOE Green Energy (OSTI)

The atomic composition of the back surface of the CdTe layer in a CdTe/CdS photovoltiac (PV) device has a significant influence on the quality of the electrical contact to this layer. This paper reports the results of a systematic study that correlates the composition of the back surface with pre-contact processing and device performance.

Levi, D.; Albin, D.; King, D.

2000-01-01T23:59:59.000Z

116

Simple shear processing of bulk BI?TE? alloys  

E-Print Network (OSTI)

The objective of this work is to determine the appropriate extrusion conditions of cast Bi?Te? alloys via equal channel angular extrusion (ECAE) to produce material that has a fine grain size (5~30[]m), uniform grain morphology and low grain boundary misorientation for improving thermoelectric and mechanical properties. The range of variables examined in this study includes: alloy type (p- and n-type) extrusion temperature (400 ~ 525?C), extrusion route (A, B, C and E), extrusion speed (0.3 ~ 0.01 in/min), and the number of extrusions (1, 2, 4 and 8). The microstructure is characterized by a polarized optical microscopy. Successful extrusions were accomplished at a temperature and strain rate that enabled dynamic recrystallization. Holding in the hot die after extrusion encouraged grain growth. The post processed grain size is found to be strongly dependent on extrusion temperature and extrusion speed. The microstructural uniformity is found to be dependent on the number of extrusions and extrusion route. Uniform equiaxial grain of 10 to 30mm average size are obtained in the p-type alloy after four extrusion passes following route E at a temperature of 500?C and an extrusion speed of 0.1 in/min. The results encourage further work and indicate ECAE is a viable method of grain refinement of Bi?Te? alloys.

Im, Jae-taek

2001-01-01T23:59:59.000Z

117

Advanced CdTe Photovoltaic Technology: September 2007 - March 2009  

DOE Green Energy (OSTI)

During the last eighteen months, Abound Solar (formerly AVA Solar) has enjoyed significant success under the SAI program. During this time, a fully automated manufacturing line has been developed, fabricated and commissioned in Longmont, Colorado. The facility is fully integrated, converting glass and semiconductor materials into complete modules beneath its roof. At capacity, a glass panel will enter the factory every 10 seconds and emerge as a completed module two hours later. This facility is currently undergoing trials in preparation for large volume production of 120 x 60 cm thin film CdTe modules. Preceding the development of the large volume manufacturing capability, Abound Solar demonstrated long duration processing with excellent materials utilization for the manufacture of high efficiency 42 cm square modules. Abound Solar prototype modules have been measured with over 9% aperture area efficiency by NREL. Abound Solar demonstrated the ability to produce modules at industry leading low costs to NREL representatives. Costing models show manufacturing costs below $1/Watt and capital equipment costs below $1.50 per watt of annual manufacturing capacity. Under this SAI program, Abound Solar supported a significant research and development program at Colorado State University. The CSU team continues to make progress on device and materials analysis. Modeling for increased device performance and the effects of processing conditions on properties of CdTe PV were investigated.

Barth, K.

2011-05-01T23:59:59.000Z

118

CdTe Feedstock Development and Validation: Cooperative Research and Development Final Report, CRADA Number CRD-08-00280  

DOE Green Energy (OSTI)

The goal of this work was to evaluate different CdTe feedstock formulations (feedstock provided by Redlen) to determine if they would significantly improve CdTe performance with ancillary benefits associated with whether changes in feedstock would affect CdTe cell processing and possibly reliability of cells. Feedstock also included attempts to intentionally dope the CdTe with pre-selected elements.

Albin, D.

2011-05-01T23:59:59.000Z

119

Investigation of Junction Properties of CdS/CdTe Solar Cells and their Correlation to Device Properties (Presentation)  

DOE Green Energy (OSTI)

The objective of the Junction Studies are: (1) understand the nature of the junction in the CdTe/CdS device; (2) correlate the device fabrication parameters to the junction formation; and (3) develop a self consistent device model to explain the device properties. Detailed analysis of CdS/CdTe and SnO{sub 2}/CdTe devices prepared using CSS CdTe is discussed.

Dhere, R. G.; Zhang, Y.; Romero, M. J.; Asher, S. E.; Young, M.; To, B.; Noufi, R.; Gessert, T. A.

2008-05-01T23:59:59.000Z

120

Phase formation and phase transformations in Bi-Te films with nanoscale thickness  

Science Conference Proceedings (OSTI)

The processes of phase formation are studied in a binary Bi-Te system using the kinematic electron diffraction technique. It is established that, in the case of both simultaneous and layer-by-layer deposition of bismuth and tellurium and irrespective of the order of their deposition, phases with compositions Bi{sub 2}Te{sub 3} and BiTe are formed at the condensation plane in the amorphous and crystalline state, respectively. The amorphous Bi{sub 2}Te{sub 3} phase is stable at room temperature and crystallizes at a temperature of 423 K. It is shown that ordering of the phase BiTe is not a consequence of atomic order of the structure; rather, it is caused by the real structure of the object (by blocks)

Akhmedov, K. M. [National Academy of Sciences of Azerbaijan, Institute of Physics (Azerbaijan)], E-mail: axmedovqurban@rambler.ru

2008-09-15T23:59:59.000Z

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121

V-183: Cisco TelePresence TC and TE Bugs Let Remote Users Deny Service and  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

3: Cisco TelePresence TC and TE Bugs Let Remote Users Deny 3: Cisco TelePresence TC and TE Bugs Let Remote Users Deny Service and Remote Adjacent Authenticated Users Gain Root Shell Access V-183: Cisco TelePresence TC and TE Bugs Let Remote Users Deny Service and Remote Adjacent Authenticated Users Gain Root Shell Access June 21, 2013 - 6:00am Addthis PROBLEM: Three vulnerabilities were reported in Cisco TelePresence TC and TE PLATFORM: The following product models are affected by the vulnerabilities: Cisco TelePresence MX Series Cisco TelePresence System EX Series Cisco TelePresence Integrator C Series Cisco TelePresence Profiles Series running Cisco TelePresence Quick Set Series Cisco IP Video Phone E20 ABSTRACT: Cisco TelePresence TC and TE Software contain two vulnerabilities in the implementation of the Session Initiation Protocol (SIP) that could allow an

122

Health and environmental hazards of CdTe photovoltaic module production, use and decommissioning  

DOE Green Energy (OSTI)

Health and environmental (H&E) risks presented by CdTe photovoltaic module production, use and decommissioning have been reviewed and discussed by several authors. Several H&E concerns exit. The estimated risks are based on extrapolations of toxicity, environmental mobility, and bioavailability data for other inorganic cadmium compounds. Little information, however, is available about CdTe itself. In response to the increased interest in CdTe, Brookhaven National Laboratory (BNL) has been engaged in a cooperative research program with the National Institute of Environmental Health Sciences (NIEHS), the Fraunhofer Institute for Solid State Technology (IFT), and the GSF Institute of Chemical Ecology to develop fundamental toxicological and environmental data for CdTe. This paper describes the results of these studies, and their potential implications with respect to the H&E hazards presented by CdTe module production, use and decommissioning.

Moskowitz, P.D. [Brookhaven National Lab., Upton, NY (United States); Steinberger, H. [Fraunhofer Institut fur Festkorpertechnologie, Munchen (Germany); Thumm, W. [GSF-Institute of Ecological Chemistry, Oberschleissheim (Germany)

1995-02-01T23:59:59.000Z

123

Te Inclusions in CZT Detectors: New Method for Correcting Their Adverse Effects  

Science Conference Proceedings (OSTI)

Both Te inclusions and point defects can trap the charge carriers generated by ionizing particles in CdZnTe (CZT) detectors. The amount of charge trapped by point defects is proportional to the carriers drift time and can be corrected electronically. In the case of Te inclusions, the charge loss depends upon their random locations with respect to the electron cloud. Consequently, inclusions introduce fluctuations in the charge signals, which cannot be easily corrected. In this paper, we describe direct measurements of the cumulative effect of Te inclusions and its influence on the response of CZT detectors of different thicknesses and different sizes and concentrations of Te inclusions. We also discuss a means of partially correcting their adverse effects.

Bolotnikov, A.E.; Babalola, S.; Camarda, G.S.; Cui, Y.; Egarievwe, S.U.; Hawrami, R.; Hossain, A.; Yang, G.; James, R.B.

2009-10-25T23:59:59.000Z

124

Te Inclusions in CZT Detectors: New Method for Correcting Their Adverse Effects  

Science Conference Proceedings (OSTI)

Both Te inclusions and point defects can trap the charge carriers generated by ionizing particles in CdZnTe (CZT) detectors. The amount of charge trapped by point defects is proportional to the carriers' drift time and can be corrected electronically. In the case of Te inclusions, the charge loss depends upon their random locations with respect to the electron cloud. Consequently, inclusions introduce fluctuations in the charge signals, which cannot be easily corrected. In this paper, we describe direct measurements of the cumulative effect of Te inclusions and its influence on the response of CZT detectors of different thicknesses and different sizes and concentrations of Te inclusions. We also discuss a means of partially correcting their adverse effects.

Bolotnikov, A.; Babaloa, S; Camarda, G; Cui, Y; Egarievwe, S; Hawrami, R; Hossain, A; Yang, G; James, R

2010-01-01T23:59:59.000Z

125

Vibrational signatures of OTe and OTe-VCd in CdTe: A first principles study  

Science Conference Proceedings (OSTI)

Chen et al. [Phys. Rev. Lett. 96 (2006) 035508] experimentally observed vibrational signatures related to defects in oxygen-doped CdTe using ultrahigh resolution Fourier transform infrared (FTIR) spectroscopy. They observed an absorption peak at 350 cm{sup -1}. In addition, for samples grown under certain conditions, they observed two higher frequency peaks (1097 and 1108 cm{sup -1}) at low temperature that merged into one at room-temperature. They attributed the low-frequency peak (350 cm{sup -1}) to the vibration of O{sub Te} and the two higher frequency peaks to the vibrational modes of a O{sub Te}-V{sub Cd} complex. Subsequently, they reported similar modes around 1100 cm{sup -1} in O-doped CdSe [Phys. Rev. Lett. 101 (2008) 195502] which were attributed to an O{sub Se}-V{sub Cd} complex. We employed first-principles DFT calculations to calculate the vibrational modes of O{sub Te} and O{sub Te}-V{sub Cd} complex in CdTe. Our calculations show that the 350 cm{sup -1} mode is consistent with O{sub Te}. However, the frequencies of the modes around 1100 cm{sup -1} are more than twice the expected frequencies for O{sub Te}-V{sub Cd} complexes in CdTe (or O{sub Se}-V{sub Cd} in CdSe), indicating that the O{sub Te}-V{sub Cd} complex cannot be the cause of the observed 1100 cm{sup -1} modes. A search for a new defect model is in order.

Thienprasert, J.T. [Kasetsart University, Thailand; Limpijumnong, Sukit [Kasetsart University, Thailand; Janotti, Anderson [University of California, Santa Barbara; Van de Walle, C.G. [University of California, Santa Barbara; Zhang, Lijun [ORNL; Du, Mao-Hua [ORNL; Singh, David J [ORNL

2010-01-01T23:59:59.000Z

126

A GENERAL RELATIVISTIC EXTERNAL COMPTON-SCATTERING MODEL FOR TeV EMISSION FROM M87  

SciTech Connect

M87 is the first detected non-blazar extragalactic tera-electron-volt (TeV) source with rapid variation and a very flat spectrum in the TeV band. To explain the two peaks in the spectral energy distribution of the nucleus of M87, which is similar to that of blazars, the most commonly adopted models are the synchrotron self-Compton-scattering models and the external inverse Compton (EIC) scattering models. Considering that there is no correlated variation in the soft band (from radio to X-ray) matching the TeV variation and that the TeV sources should not suffer from {gamma}{gamma} absorption due to the flat TeV spectrum, the EIC models are advantageous in modeling the TeV emission from M87. In this paper, we propose a self-consistent EIC model to explain the flat TeV spectrum of M87 within the framework of fully general relativity, where the background soft photons are from the advection-dominated accretion flow around the central black hole, and the high-energy electrons are from the mini-jets that are powered by the magnetic reconnection in the main jet. In our model, both the TeV flares observed in the years 2005 and 2008 could be well explained: the {gamma}{gamma} absorption for TeV photons is very low, even inside the region very close to the black hole 20R{sub g} {approx} 50R{sub g} ; at the same region, the average EIC cooling time ({approx}10{sup 2} {approx} 10{sup 3} s) is short, which is consistent with the observed timescale of the TeV variation. Furthermore, we also discuss the possibility that the accompanying X-ray flare in 2008 is due to the direct synchrotron radiation of the mini-jets.

Cui Yudong; Yuan Yefei [Key Laboratory for Research in Galaxies and Cosmology, Department of Astronomy, University of Sciences and Technology of China, CAS, Hefei, Anhui 230026 (China); Li Yanrong; Wang Jianmin, E-mail: yfyuan@ustc.edu.cn [Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, CAS, 19B Yuquan Road, Beijing 100049 (China)

2012-02-20T23:59:59.000Z

127

Plasma graviton production in TeV-scale gravity  

E-Print Network (OSTI)

We develop the theory of interaction of classical plasma with Kaluza-Klein (KK) gravitons in the ADD model of TeV-scale gravity. Plasma is described within the kinetic approach as the system of charged particles and Maxwell field both confined on the brane. Interaction with multidimensional gravity living in the bulk with $n$ compact extra dimensions is introduced within the linearized theory. The KK gravitons emission rates are computed taking into account plasma collective effects through the two-point correlation functions of the fluctuations of the plasma energy-momentum tensor. Apart from known mechanisms (such as bremsstrahlung and gravi-Primakoff effect) we find essentially collective channels such as the coalescence of plasma waves into gravitons which may be manifest in turbulent plasmas. Our results indicate that commonly used rates of the KK gravitons production in stars and supernovae may be underestimated.

E. Yu. Melkumova

2010-12-14T23:59:59.000Z

128

Additional Characterization of Min-K TE-1400 Thermal Insulation  

Science Conference Proceedings (OSTI)

Min-K 1400TE (Thermal Ceramics, Augusta, Georgia) insulation material was further characterized at Oak Ridge National Laboratory (ORNL) for use in structural applications under gradient temperature conditions in an inert environment. Original characterization of Min-K was undertaken from April 1997 to July 2008 to determine its high temperature compressive strength and stress relaxation behavior up to 900 C in helium along with the formulation of a general model for the mechanical behavior exhibited by Min-K under these conditions. The additional testing described in this report was undertaken from April 2009 to June 2010 in an effort to further evaluate the mechanical behavior of Min-K when subjected to a variety of conditions including alternative test temperatures and time scales than previously measured. The behavior of Min-K under changing environments (temperature and strain), lateral loads, and additional isothermal temperatures was therefore explored.

Hemrick, James Gordon [ORNL; King, James [ORNL

2011-01-01T23:59:59.000Z

129

Development of Substrate Structure CdTe Photovoltaic Devices with Performance Exceeding 10%: Preprint  

DOE Green Energy (OSTI)

Most work on CdTe-based solar cells has focused on devices with a superstrate structure. This focus is due to the early success of the superstrate structure in producing high-efficiency cells, problems of suitable ohmic contacts for lightly doped CdTe, and the simplicity of the structure for manufacturing. The development of the CdCl2 heat treatment boosted CdTe technology and perpetuated the use of the superstrate structure. However, despite the beneficial attributes of the superstrate structure, devices with a substrate structure are attractive both commercially and scientifically. The substrate structure eliminates the need for transparent superstrates and thus allows the use of flexible metal and possibly plastic substrates. From a scientific perspective, it allows better control in forming the junction and direct access to the junction for detailed analysis. Research on such devices has been limited. The efficiency of these devices has been limited to around 8% due to low open-circuit voltage (Voc) and fill factor. In this paper, we present our recent device development efforts at NREL on substrate-structure CdTe devices. We have found that processing parameters required to fabricate high-efficiency substrate CdTe PV devices differ from those necessary for traditional superstrate CdTe devices. We have worked on a variety of contact materials including Cu-doped ZnTe and CuxTe. We will present a comparative analysis of the performance of these contacts. In addition, we have studied the influence of fabrication parameters on junction properties. We will present an overview of our development work, which has led to CdTe devices with Voc values of more than 860 mV and NREL-confirmed efficiencies approaching 11%.

Dhere, R. G.; Duenow, J. N.; DeHart, C. M.; Li, J. V.; Kuciauskas, D.; Gessert, T. A.

2012-08-01T23:59:59.000Z

130

Low cost sprayed CdTe solar cell research. First quarterly progress report, 15 August-14 November 1979  

DOE Green Energy (OSTI)

During the first quarter of this contract, facilities for the spray pyrolysis deposition of CdTe thin films using a process anolagous to that used to spray deposit device-quality films of CdS were prepared. A Te salt, ..beta..-(CH/sub 3/)/sub 2/TeI/sub 2/, suitable for use in the spray process was synthesized. The facilities were shown to function properly by the successful spraying of good quality CdS thin films. A number of initial spray experiments were conducted utilizing the ..beta..-(CH/sub 3/)/sub 2/TeI/sub 2/ and other inorganic tellurium-bearing compounds which also show great promise in producing low-cost sprayed CdTe solar cells. Initial chemical tests of these films indicated the presence of both Cd and Te, and x-ray diffraction analysis is presently underway to determine the actual concentration of CdTe.

Sienkiewicz, P.; Lis, S.; Serreze, H.B.; Entine, G.

1979-12-01T23:59:59.000Z

131

Recent results from the Milagro TeV gamma-ray observatory  

E-Print Network (OSTI)

Milagro is a gamma-ray observatory employing a water Cherenkov detector to observe extensive air showers produced by high-energy particles impacting in the Earth's atmosphere. We discuss the first detection of TeV gamma-rays from the Galactic plane and report the detection of an extended TeV source coincident with the EGRET source 3EG J0520+2556, and the observation of TeV emission from the Cygnus region of our Galaxy. We also summarize the status of our search for Very High Energy (VHE) emission from satellite-triggered Gamma Ray Bursts (GRBs) and discuss plans for the next generation water Cherenkov detector.

Parkinson, P M S

2005-01-01T23:59:59.000Z

132

Thin-film CdTe and CuInSe{sub 2} photovoltaic technologies  

DOE Green Energy (OSTI)

Total-area conversion efficiency of 15%--15.8% have been achieved for thin-film CdTe and CIS solar cells. Modules with power output of 5--53 W have been demonstrated by several groups world-wide. Critical processes and reaction pathways for achieving excellent PV devices have been eluciated. Research, development and technical issues have been identified, which could result in potential improvements in device and module performance. A 1-kW thin-film CdTe array has been installed and is being tested. Multimegawatt thin-film CdTe manufacturing plants are expected to be completed in 1-2 years.

Ullal, H.S.; Zweibel, K.; von Roedern, B.G.

1993-08-01T23:59:59.000Z

133

Chapter 1.19: Cadmium Telluride Photovoltaic Thin Film: CdTe  

Science Conference Proceedings (OSTI)

The chapter reviews the history, development, and present processes used to fabricate thin-film, CdTe-based photovoltaic (PV) devices. It is intended for readers who are generally familiar with the operation and material aspects of PV devices but desire a deeper understanding of the process sequences used in CdTe PV technology. The discussion identifies why certain processes may have commercial production advantages and how the various process steps can interact with each other to affect device performance and reliability. The chapter concludes with a discussion of considerations of large-area CdTe PV deployment including issues related to material availability and energy-payback time.

Gessert, T. A.

2012-01-01T23:59:59.000Z

134

Light-Induced Tellurium Enrichment on CdZnTe Crystal Surfaces Detected by Raman Spectroscopy  

Science Conference Proceedings (OSTI)

CdZnTe (CZT) crystals can be grown under controlled conditions to produce high-quality crystals to be used as room-temperature radiation detectors. Even the best crystal growth methods result in defects, such as tellurium secondary phases, that affect the crystal's performance. In this study, CZT crystals were analyzed by micro-Raman spectroscopy. The growth of Te rich areas on the surface was induced by low-power lasers. The growth was observed versus time with low-power Raman scattering and was observed immediately under higher-power conditions. The detector response was also measured after induced Te enrichment.

Hawkins, Samantha A.; Villa-Aleman, Eliel; Duff, Martine C.; Hunter, Doug B.; Burger, Arnold; Groza, Michael; Buliga, Vladimir; Black, David R. (SRNL); (NIST); (Fisk U)

2008-12-08T23:59:59.000Z

135

POLARIZATION STUDIES OF CdZnTe DETECTORS USING SYNCHROTRON X-RAY RADIATION.  

Science Conference Proceedings (OSTI)

New results on the effects of small-scale defects on the charge-carrier transport in single-crystal CdZnTe (CZT) material were produced. We conducted detailed studies of the role of Te inclusions in CZT by employing a highly collimated synchrotron x-ray radiation source available at Brookhaven's National Synchrotron Light Source (NSLS). We were able to induce polarization effects by irradiating specific areas with the detector. These measurements allowed the first quantitative comparison between areas that are free of Te inclusions and those with a relatively high concentration of inclusions. The results of these polaration studies will be reported.

CAMARDA,G.S.; BOLOTNIKOV, A.E.; CUI, Y.; HOSSAIN, A.; JAMES, R.B.

2007-07-01T23:59:59.000Z

136

XPS and AES Studies of Cu/CdTe(111)-B  

DOE Green Energy (OSTI)

Copper is frequently used as a p-type dopant to improve the performance of back contacts in CdTe thin-film solar cells. In this study, surface-analysis techniques are used to probe fundamental interactions between Cu and the CdTe(111)-B surface. The results presented here were facilitated by the newly constructed surface-analysis cluster tool in the Measurements and Characterization Division at NREL; they reveal a host of fundamental phenomena that occur in the Cu/CdTe system.

Teeter, G.; Gessert, T. A.; Asher, S. E.

2005-01-01T23:59:59.000Z

137

Spectroscopy of low energy solar neutrinos using CdTe detectors  

E-Print Network (OSTI)

The usage of a large amount of CdTe(CdZnTe) semiconductor detectors for solar neutrino spectroscopy in the low energy region is investigated. Several different coincidence signals can be formed on five different isotopes to measure the Be-7 neutrino line at 862 keV in real-time. The most promising one is the usage of Cd-116 resulting in 89 SNU. The presence of Te-125 permits even the real-time detection of pp-neutrinos. A possible antineutrino flux above 713 keV might be detected by capture on Cd-106 .

K. Zuber

2002-06-19T23:59:59.000Z

138

Spectroscopy of low energy solar neutrinos using CdTe detectors  

E-Print Network (OSTI)

The usage of a large amount of CdTe(CdZnTe) semiconductor detectors for solar neutrino spectroscopy in the low energy region is investigated. Several different coincidence signals can be formed on five different isotopes to measure the Be-7 neutrino line at 862 keV in real-time. The most promising one is the usage of Cd-116 resulting in 89 SNU. The presence of Te-125 permits even the real-time detection of pp-neutrinos. A possible antineutrino flux above 713 keV might be detected by capture on Cd-106 .

Zuber, K

2003-01-01T23:59:59.000Z

139

Cd1-xMnxTe semimagnetic semiconductors for ultrafast spintronics and magnetooptics  

Science Conference Proceedings (OSTI)

We present ultrafast optical characterization of Cd1-xMnxTe single crystals with high (x>0.5-Mn) concentration, studied by magnetooptical sampling and time-resolved magnetization modulation spectroscopy. We have demonstrated that ...

R. Rey-de-Castro; Daozhi Wang; A. Verevkin; A. Mycielski; R. Sobolewski

2005-01-01T23:59:59.000Z

140

Glass-like thermal transport in AgSbTe2 | ORNL  

NLE Websites -- All DOE Office Websites (Extended Search)

Glass-like thermal transport in AgSbTe2: nano-scale insights to improve thermoelectric efficiency May 16, 2013 Inelastic neutron scattering data showing the phonon dispersions...

Note: This page contains sample records for the topic "graphi te hoback" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Appendix B: CArBon dioxide CApture teChnology SheetS  

NLE Websites -- All DOE Office Websites (Extended Search)

teChnology uPDate, may 2013 eleCtroChemiCal membrane for Carbon DioxiDe CaPture & Power generation primary project goals FuelCell Energy, Inc. (FCE) is developing an...

142

Z' Bosons, the NuTeV Anomaly, and the Higgs Boson Mass  

E-Print Network (OSTI)

NuTeV Anomaly, and the Higgs Boson Mass Michael S. Chanowitzpredicted value of the Higgs boson mass, from ? 60 to ? 120from an increase in the Higgs boson mass. There is a vast

Chanowitz, Michael S

2009-01-01T23:59:59.000Z

143

Processing Effects on Junction Interdiffusion in CdS/CdTe Polycrystalline Devices  

DOE Green Energy (OSTI)

The performance of CdS/CdTe solar cells is strongly impacted by the process used to grow the CdS layer. CdS films grown by chemical-bath deposition (CBD) exhibit lower sublimation (CSS).

Albin, D.; Yan, Y.; King, D.; Moutinho, H.; Jones, K.; Matson, R.; Al-Jassim, M.

2000-01-01T23:59:59.000Z

144

ZB/WZ Band Offsets and Carrier Localization in CdTe Solar Cells  

DOE Green Energy (OSTI)

Using the first principles band-structure method, we studied systematically the stability and electronic structure of CdX (X=S, Se, and Te) semiconductors with the zinc-blende (ZB) and wurtzite (WZ) crystal structures.

Wei, S.-H.; Zhang, S. B.

2000-01-01T23:59:59.000Z

145

Mechanical properties of highly oriented FeSe0.5Te0.5 superconductor  

Science Conference Proceedings (OSTI)

We have synthesized highly oriented samples of the superconducting compound FeSe0.5Te0.5 and investigated its mechanical properties. These samples were characterized by scanning electron microscopy(SEM) with energy-dispersive analysis

Jorge Luiz Pimentel Jnior; Paulo Pureur; Cristiano Santos Lopes; Francisco Carlos Serbena; Carlos Eugnio Foerster; Simone Aparecida da Silva; Alcione Roberto Jurelo; Adilson Luiz Chinelatto

2012-01-01T23:59:59.000Z

146

Characterization of CdTe Nanoparticles Fabricated by Pulsed Electron Deposition Technique at Different Ablation Parameters  

Science Conference Proceedings (OSTI)

Telluride (CdTe) is a front-runner photovoltaic (PV) material because it has already attained efficiencies above 16%. The fabrication of CdTe nanoparticles has aroused considerable interest because of their potential application as active layer in organic/inorganic hybrid solar cells. They can also be used for sensitisation of wide band gap semiconductors. In this work, we explore pulsed electron beam deposition (PED) technique to fabricate CdTe nanoparticles. Two ablation parameters, namely background gas pressure and electron energy were varied to investigate their effects on the nanoparticle formation. AFM and optical transmission measurements indicate that we have fabricated CdTe nanocrystalline films exhibiting quantum confinement effect. These films contain scattered nanoparticles with diameters varying from 40 nm to 500 nm, which contribute to the optical absorption near the bulk bandgap energy. However, increasing the background pressure to 19 mTorr improves the nanocrystalline film uniformity.

Jackson, E.; Aga, R. Jr.; Steigerwald, A.; Ueda, A.; Pan, Z.; Collins, W. E.; Mu, R. [Department of Physics, Fisk University, 1000 17th Ave N, Nashville TN 37208 (United States)

2008-03-13T23:59:59.000Z

147

Low-cost CdZnTe devices for cascade cell application  

DOE Green Energy (OSTI)

This report describes a research program to develop a low-cost technique for producing Cd{sub 1-x}Zn{sub x}Te devices for cascade solar cell applications. The technique involves a two-stage process for fabricating such devices with a band gap of about 1.7 eV and a transparent contact layer of low-resistivity ZnTe. In the first stage, thin films of Cd, Zn, and Te are deposited in stacked layers as Cd{sub 1-x}An{sub x}Te. The second stage involves hearing and reacting the layers to form the compound. At first, electrodeposition was used for depositing the layers to successfully fabricate Dc{sub 1-x}Zn{sub x}Te thin-film devices. These films were also intrinsically doped with copper. For the first time, transparent ZnTe films of low resistivity were obtained in a two-stage process; preliminary solar cells using films with low Zn content were demonstrated. A second phase of the project involved growing films with higher Zn content (>15%). Such films were grown on CdS-coated substrates for fabricating devices. The effects of the solar-cell processing steps on the Cd{sub 1-x}Zn{sub x}Te and CdS/Cd{sub 1-x}Zn{sub x}Te interfaces were studied; results showed that the nature of the interface depended on the stoichiometry of the Cd{sub 1-x}Zn{sub x}Te thin film. A sharp interface was observed for the CdS/CdTe structures, but the interface became highly diffused as the Zn content in the absorber layer increased above 15%. The interaction between the CdS window layer and the Cd{sub 1-x}Zn{sub x}Te absorber layer was found to result from an exchange reaction between Zn in the absorber layer and the thin CdS film. 14 refs., 10 figs.

Basol, B.M.; Kapur, V.K. (International Solar Electric Technology, Inglewood, CA (USA))

1990-11-01T23:59:59.000Z

148

Deformation and shape transitions in hot rotating neutron deficient Te isotopes  

SciTech Connect

Evolution of the nuclear shapes and deformations under the influence of temperature and rotation is investigated in Te isotopes with neutron number ranging from the proton drip line to the stability valley. Spin dependent critical temperatures for the shape transitions in Te nuclei are computed. Shape transitions from prolate at low temperature and spin to oblate via triaxiality are seen with increasing neutron number and spin.

Aggarwal, Mamta [UM-DAE Centre for Excellence in Basic Sciences, University of Mumbai, Kalina Campus, Mumbai 400 098 (India); Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005 (India); Mazumdar, I. [Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005 (India)

2009-08-15T23:59:59.000Z

149

Preparation and properties of evaporated CdTe films compared with single-crystal CdTe. Progress report no. 6, February 1, 1982-April 30, 1982  

DOE Green Energy (OSTI)

Films of n-type CdTe:In have been deposited by hot-wall vacuum evaporation (HWVE) on 7059 glass substrates, BaF/sub 2/ single crystal substrates, metal (Pt, Cr, Mo, Al) coated glass substrates, and single crystal p-type CdTe substrates. Films deposited on 7059 glass show typically a dark resistivity of 2 x 10/sup 5/ ohm-cm and a light resistivity of 3 x 10/sup 2/ ohm-cm. With increasing In source temperature, the resistivity decreases, but actually increases slightly again if the T/sub In/ is raised above 600/sup 0/C. Photoexcitation increases the electron density but does not affect the electron mobility. It appears that the grains are depleted in the dark. Films deposited on BaF/sup 2/ show dark resistivity of about 5 ohm-cm and light resistivity of about 2 ohm-cm, corresponding to electron densities of about 3 x 10/sup 16/ cm/sup -3/ and electron mobilities of about 30 cm/sup 2//V-sec. For doping levels abpove 10/sup 16/ cm/sup -3/ photoexcitation increases the mobility, but not the electron density; it appears that the grains are not depleted in the dark in this case. Cr coated 7059 glass makes an ohmic contact to n-type CdTe films. A Schottky diode formed with a 100A thick Au layer showed V/sub oc/ = 0.46 V, J/sub sc/ = 9 mA/cm/sup 2/ and a solar efficiency of about 2%. An n/p homojunction device was made by HWVE deposition of a 1.5 ..mu..m thick n-type CdTe layer on a p-type CdTe single crystal substrate. Values of V/sub oc/ = 0.73 V and J/sub sc/ = 0.24 mA/cm/sup 2/ were obtained. Grain boundary investigations showed the additive quality of two independent grain boundaries when measured in series, and tested the effects of passivation by Au, Cu, Li and H/sub 2/ in p-type CdTe grain boundaries, and In in n-type CdTe grain boundaries. Marked decreases in grain boundary resistance were observed after Li diffusion and H/sub 2/ diffusion in p-type CdTe.

Bube, R H

1982-01-01T23:59:59.000Z

150

Preparation and properties of evaporated CdTe films compared with single crystal CdTe. Progress report No. 4, August 1-October 31, 1981  

DOE Green Energy (OSTI)

The hot-wall vacuum evaporation system is nearly complete and the first films are expected in early December. CdTe homojunction cells were theoretically modelled and to some extent tested experimentally using the n-type CdTe film on p-type CdTe crystal homojunction cells previously deposited at Linz. Modelling emphasizes the known importance of surface recombination velocity for such homojunction cells. The n-type layer on the experimental cell was thinned by etching from 5 micrometers to 1.5 micrometers, with a corresponding increase in short-circuit current from 0.1 to 1 mA/cm/sup 2/. This behavior is as theoretically expected; to obtain a short-circuit current of 11 mA/cm/sup 2/, as required for a 10% cell, requires a thickness of about 0.2 micrometers for a surface recombination velocity of 10/sup 6/ cm/sec and other realistic cell parameters. By doping experiments on single crystal CdTe, it has been shown that the hole density does decrease when the P dopant density is decreased below a critical value in CdTe:P crystals, thus eliminating the possibility that the major acceptors in the P-doped crystals were not P impurity. Attempts to heavily dope CdTe with As were less successful, but this may be due to the use of elemental As as the dopant in this case rather than a compound of the dopant. Cs was shown to be an effective dopant of CdTe and resistivities as low as 0.3 ohm-cm corresponding to hole densities in the low 10/sup 17/ cm/sup -3/ range were obtained. An apparent correlation between the low-temperature barrier height associated with a grain boundary in CdTe and the angle of mismatch between the two grains has been observed. Improved capacitance of grain boundary measurements should yield defect densities.

Bube, R H

151

Valence Band Structure of Highly Efficient p-type Thermoelectric PbTe-PbS Alloys  

Science Conference Proceedings (OSTI)

New experimental evidence is given relevant to the temperature-dependence of valence band structure of PbTe and PbTe1-xSx alloys (0.04 x 0.12), and its effect on the thermoelectric figure of merit zT. The x = 0.08 sample has zT ~ 1.55 at 773K. The magnetic field dependence of the high-temperature Hall resistivity of heavily p-type (> 1019 cm-3) Na-doped PbTe1-xSx reveals the presence of high-mobility electrons. This put in question prior analyses of the Hall coefficient and the conclusion that PbTe would be an indirect gap semiconductor at temperatures where its zT is optimal. Possible origins for these electrons are discussed: they can be induced by photoconductivity, or by the topology of the Fermi surface when the L and -bands merge. Negative values for the low-temperature thermopower are also observed. Our data show that PbTe continues to be a direct gap semiconductor at temperatures where the zT and S2 of p-type PbTe are optimal e.g. 700-900K. The previously suggested temperature induced rapid rise in energy of the heavy hole LVB relative to the light hole UVB is not supported by the experimental data.

Jaworski, C. M. [Ohio State University; Nielsen, Mechele [Ohio State University; Wang, Hsin [ORNL; Girard, Steven N. [Northwestern University, Evanston; Cai, Wei [ORNL; Porter, Wallace D [ORNL; Kanatzidis, Mercouri G. [Northwestern University, Evanston; Heremans, J. P. [Ohio State University

2013-01-01T23:59:59.000Z

152

Can TeVeS avoid Dark Matter on galactic scales?  

E-Print Network (OSTI)

A fully relativistic analysis of gravitational lensing in TeVeS is presented. By estimating the lensing masses for a set of six lenses from the CASTLES database, and then comparing them to the stellar mass, the deficit between the two is obtained and analysed. Considering a parametrised range for the TeVeS function $mu(y)$, which controls the strength of the modification to gravity, it is found that on galactic scales TeVeS requires additional dark matter with the commonly used $mu(y)$. A soft dependence of the results on the cosmological framework and the TeVeS free parameters is discussed. For one particular form of $mu(y)$, TeVeS is found to require very little dark matter. This choice is however ruled out by rotation curve data. The inability to simultaneously fit lensing and rotation curves for a single form of $mu(y)$ is a challenge to a "no dark matter" TeVeS proposal.

Nick E. Mavromatos; Mairi Sakellariadou; Muhammad Furqaan Yusaf

2009-01-25T23:59:59.000Z

153

Oxygen Incorporation During Fabrication of Substrate CdTe Photovoltaic Devices: Preprint  

DOE Green Energy (OSTI)

Recently, CdTe photovoltaic (PV) devices fabricated in the nonstandard substrate configuration have attracted increasing interest because of their potential compatibility with flexible substrates such as metal foils and polymer films. This compatibility could lead to the suitability of CdTe for roll-to-roll processing and building-integrated PV. Currently, however, the efficiencies of substrate CdTe devices reported in the literature are significantly lower ({approx}6%-8%) than those of high-performance superstrate devices ({approx}17%) because of significantly lower open-circuit voltage (Voc) and fill factor (FF). In our recent device development efforts, we have found that processing parameters required to fabricate high-efficiency substrate CdTe PV devices differ from those necessary for traditional superstrate CdTe devices. Here, we investigate how oxygen incorporation in the CdTe deposition, CdCl2 heat treatment, CdS deposition, and post-deposition heat treatment affect device characteristics through their effects on the junction. By adjusting whether oxygen is incorporated during these processing steps, we have achieved Voc values greater than 860 mV and efficiencies greater than 10%.

Duenow, J. N.; Dhere, R. G.; Kuciauskas, D.; Li, J. V.; Pankow, J. W.; DeHart, C. M.; Gessert, T. A.

2012-06-01T23:59:59.000Z

154

Defect Levels of Indium-doped CdMnTe Crystals  

Science Conference Proceedings (OSTI)

Using photoluminescence (PL) and current deep-level transient spectroscopy (I-DLTS), we investigated the electronic defects of indium-doped detector-grade CdMnTe:In (CMT:In) crystals grown by the vertical Bridgman method. We similarly analyzed CdZnTe:In (CZT:In) and undoped CdMnTe (CMT) crystals grown under the amount of same level of excess Te and/or indium doping level to detail the fundamental properties of the electronic defect structure more readily. Extended defects, existing in all the samples, were revealed by synchrotron white beam x-ray diffraction topography and scanning electron microscopy. The electronic structure of CMT is very similar to that of CZT, with shallow traps, A-centers, Cd vacancies, deep levels, and Te antisites. The 1.1-eV deep level, revealed by PL in earlier studies of CZT and CdTe, were attributed to dislocation-induced defects. In our I-DLTS measurements, the 1.1-eV traps showed different activation energies with applied bias voltage and an exponential dependence on the trap-filling time, which are typical characteristics of dislocation-induced defects. We propose a new defect-trap model for indium-doped CMT crystals.

K Kim; A Bolotinikov; G Camarda; R Gul; A Hossain; G Yang; Y Cui; R James

2011-12-31T23:59:59.000Z

155

Molecular Beam Epitaxial Growth of Bi2Te3 and Sb2Te3 Topological Insulators on GaAs (111) Substrates: A Potential Route to Fabricate Topological Insulator p-n Junction  

E-Print Network (OSTI)

High quality Bi2Te3 and Sb2Te3 topological insulators films were epitaxially grown on GaAs (111) substrate using solid source molecular beam epitaxy. Their growth and behavior on both vicinal and non-vicinal GaAs (111) substrates were investigated by reflection high-energy electron diffraction, atomic force microscopy, x-ray diffraction, and high resolution transmission electron microscopy. It is found that non-vicinal GaAs (111) substrate is better than a vicinal substrate to provide high quality Bi2Te3 and Sb2Te3 films. Hall and magnetoresistance measurements indicate that p type Sb2Te3 and n type Bi2Te3 topological insulator films can be directly grown on a GaAs (111) substrate, which may pave a way to fabricate topological insulator p-n junction on the same substrate, compatible with the fabrication process of present semiconductor optoelectronic devices.

Zhaoquan Zeng; Timothy A. Morgan; Dongsheng Fan; Chen Li; Yusuke Hirono; Xian Hu; Yanfei Zhao; Joon Sue Lee; Zhiming M. Wang; Jian Wang; Shuiqing Yu; Michael E. Hawkridge; Mourad Benamara; Gregory J. Salamo

2013-01-03T23:59:59.000Z

156

DEVELOPMENT OF CdZnTe RADIATION DETECTORS  

Science Conference Proceedings (OSTI)

Cadmium Zinc Telluride (CdZnTe or CZT) is a very attractive material for room-temperature semiconductor detectors because of its wide band-gap and high atomic number. Despite these advantages, CZT still presents some material limitations and poor hole mobility. In the past decade most of the developing CZT detectors focused on designing different electrode configurations, mainly to minimize the deleterious effect due to the poor hole mobility. A few different electrode geometries were designed and fabricated, such as pixelated anodes and Frisch-grid detectors developed at Brookhaven National Lab (BNL). However, crystal defects in CZT materials still limit the yield of detector-grade crystals, and, in general, dominate the detector's performance. In the past few years, our group's research extended to characterizing the CZT materials at the micro-scale, and to correlating crystal defects with the detector's performance. We built a set of unique tools for this purpose, including infrared (IR) transmission microscopy, X-ray micro-scale mapping using synchrotron light source, X-ray transmission- and reflection-topography, current deep level transient spectroscopy (I-DLTS), and photoluminescence measurements. Our most recent work on CZT detectors was directed towards detailing various crystal defects, studying the internal electrical field, and delineating the effects of thermal annealing on improving the material properties. In this paper, we report our most recent results.

BOLOTNIKOV, A.; CAMARDA, G.; HOSSAIN, A.; KIM, K.H.; YANG, G.; GUL, R.; CUI, Y.; AND JAMES, R.B.

2011-10-23T23:59:59.000Z

157

Development of a Total Energy, Environment and Asset Management (TE2AM tm) Curriculum  

Science Conference Proceedings (OSTI)

The University of Wisconsin Department of Engineering Professional Development (EPD) has completed the sponsored project entitled, Development of a Total Energy, Environment and Asset Management (TE2AM) Curriculum. The project involved the development of a structured professional development program to improve the knowledge, skills, capabilities, and competencies of engineers and operators of commercial buildings. TE2AM advances a radically different approach to commercial building design, operation, maintenance, and end-?of-?life disposition. By employing asset management principles to the lifecycle of a commercial building, owners and occupants will realize improved building performance, reduced energy consumption and positive environmental impacts. Through our commercialization plan, we intend to offer TE2AM courses and certificates to the professional community and continuously improve TE2AM course materials. The TE2AM project supports the DOE Strategic Theme 1 -? Energy Security; and will further advance the DOE Strategic Goal 1.4 Energy Productivity. Through participation in the TE2AM curriculum, engineers and operators of commercial buildings will be eligible for a professional certificate; denoting the completion of a prescribed series of learning activities. The project involved a comprehensive, rigorous approach to curriculum development, and accomplished the following goals: 1. Identify, analyze and prioritize key learning needs of engineers, architects and technical professionals as operators of commercial buildings. 2. Design and develop TE2AM curricula and instructional strategies to meet learning needs of the target learning community. 3. Establish partnerships with the sponsor and key stakeholders to enhance the development and delivery of learning programs. 4. Successfully commercialize and sustain the training and certificate programs for a substantial time following the term of the award. The project team was successful in achieving the goals and deliverables set forth in the original proposal. Though attempts were made to adhere to the original project timeline, the team requested, and was granted a 6-?month project extension, during which time the project was completed.

None

2012-12-31T23:59:59.000Z

158

A Search for a Light Charged Higgs Boson Decaying to cs at ?s = 7 TeV.  

E-Print Network (OSTI)

??A search for a light charged Higgs boson decaying into cs is presented using data recorded in pp collisions at ?s = 7 TeV. The (more)

Martyniuk, Alex Christopher

2011-01-01T23:59:59.000Z

159

Analysis of Alternate Methods to Obtain Stabilized Power Performance of CdTe and CIGS PV Modules (Presentation)  

DOE Green Energy (OSTI)

This presentation outlines an analysis of alternate methods to obtain stabilized power performance of CdTe and CIGS PV modules.

del Cueto, J. A.; Deline, C. A.; Rummel, S.

2011-02-01T23:59:59.000Z

160

Exploring alternative symmetry breaking mechanisms at the LHC with 7, 8 and 10 TeV total energy  

E-Print Network (OSTI)

In view of the annnouncement that in 2012 the LHC will run at 8 TeV, we study the possibility of detecting signals of alternative mechanisms of ElectroWeak Symmetry Breaking, described phenomenologically by unitarized models, at energies lower than 14 TeV. A complete calculation with six fermions in the final state is performed using the PHANTOM event generator. Our results indicate that at 8 TeV some of the scenarios with TeV scale resonances are likely to be identified while models with no resonances or with very heavy ones will be inaccessible, unless the available luminosity will be much higher than expected.

Alessandro Ballestrero; Diogo Buarque Franzosi; Ezio Maina

2012-03-13T23:59:59.000Z

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161

Component Overpressure Growth and Characterization of High Resistivity CdTe Crystals for Radiation Detectors  

Science Conference Proceedings (OSTI)

Spectrometer-grade CdTe single crystals with resistivities higher than 10{sup 9} {Omega} cm have been grown by the modified Bridgman method using zone-refined precursor materials (Cd and Te) under a Cd overpressure. The grown CdTe crystals had good charge-transport properties ({mu}{tau}{sub e} = 2 x 10{sup -3} cm{sup 2} V{sup -1}, {mu}{tau}{sub h} = 8 x 10{sup -5} cm{sup 2} V{sup -1}) and significantly reduced Te precipitates compared with crystals grown without Cd overpressure. The crystal growth conditions for the Bridgman system were optimized by computer modeling and simulation, using modified MASTRAPP program, and applied to crystal diameters of 14 mm (0.55'), 38 mm (1.5'), and 76 mm (3'). Details of the CdTe crystal growth operation, structural, electrical, and optical characterization measurements, detector fabrication, and testing using {sup 241}Am (60 keV) and {sup 137}Cs (662 keV) sources are presented.

Mandal, Krishna [EIC Laboratories, Inc.; Kang, Sung Hoon [EIC Laboratories, Inc.; Choi, Michael [EIC Laboratories, Inc.; Wei, Jiuan [State University of New York, Stony Brook; Zheng, Lili [State University of New York, Stony Brook; Zhang, Hui [State University of New York, Stony Brook; Jellison Jr, Gerald Earle [ORNL; Groza, Michael [Fisk University, Nashville, TN; Burger, Arnold [Fisk University, Nashville, TN

2007-01-01T23:59:59.000Z

162

Experiments Involving Correlations Between CdTe Solar Cell Fabrication History and Intrinsic Device Stability  

DOE Green Energy (OSTI)

An orthogonal full-factorial design was used to study the effect of CdS and CdTe layer thickness, oxygen ambient during vapor CdCl2 (VCC) and the use of nitric-phosphoric (NP) acid as a pre-contact etch on the initial and stressed performance of CdS/CdTe small-area devices. The best initial device efficiency (using thinner CdS, thicker CdTe, no oxygen during VCC, and NP etch) also showed poor stability. Increasing the CdS thickness significantly improved stability with only a slight decrease in resulting initial performance. All devices used a thin margin of CdTe around the perimeter of the backcontact that was shown to significantly reduce catastrophic degradation and improve overall test statistics. The latter degradation is modeled by the formation of a weak-diode/low shunt resistance localized near the edge of finished devices. This shunting is believed to occur through the CdS/CdTe interface, rather than along the device edge, and is exacerbated by thinner CdS films.

Albin, D.; McMahon, T.; Berniard, T.; Pankow, J.; Demtsu, S.; Noufi, R.

2005-02-01T23:59:59.000Z

163

Investigation of the Charge Collection Efficiency of CdMnTe Radiation Detectors  

SciTech Connect

This paper presents the growth, fabrication and characterization of indium-doped cadmium manganese telluride (CdMnTe) crystals grown by the vertical Bridgman technique. The 10 x 10 x 1.9 mm{sup 3} samples have been fabricated, and the charge collection properties of the CdMnTe detectors have been measured. Alpha-particle spectroscopy measurements have yielded an average charge collection efficiency approaching 100%. Ion beam induced charge (IBIC) measurements have been performed by raster scanning focused 5.5 MeV {sup 4}He beams onto the detectors. Spatially resolved charge collection efficiency maps have been produced for a range of detector bias voltages. Inhomogeneities in the charge transport of the CdMnTe crystals have been associated with chains of Te inclusions within the detector bulk, and the reduction in charge collection efficiency in their locality has been quantified. It has been shown that the role of Te inclusions in degrading charge collection is reduced with increasing values of bias voltage. IBIC measurements for a range of low biases have highlighted the evolution of the charge collection uniformity across the detectors.

Bolotnikov A.; Rafiei, R.; Boardman, D.; Sarbutt, A.; Prokopovich, A.; Kim, K.; Reinhard, M.I.; James, R.B.

2012-06-01T23:59:59.000Z

164

A Search for TeV Gamma-Ray Burst Emission with the Milagro Observatory  

E-Print Network (OSTI)

The Milagro telescope monitors the northern sky for 100 GeV - 100 TeV transient emission through continuous very high energy wide-field observations. The large effective area and low energy threshold of Milagro allow it to detect very high energy gamma-ray burst emission with much higher sensitivity than previous instruments, and a fluence sensitivity at TeV energies comparable to dedicated gamma-ray burst satellites at keV-MeV energies. Observation of gamma-ray burst emission at TeV energies could place important constraints on gamma-ray burst progenitor and emission models. This study details the development of a weighted analysis technique; the implementation of this technique to perform a real time search for TeV transients of 40 seconds to 3 hours duration in the Milagro data; and the results from more than one year of observation. Between May 2nd, 2001, and May 22nd, 2002, no TeV transients of 40 seconds to 3 hours duration were observed. Upper limits on both observed and emitted high energy gamma-ray burst emission are presented.

Miguel F. Morales

2003-08-06T23:59:59.000Z

165

An Experiment to Locate the Site of TeV Flaring in M87  

SciTech Connect

We describe a Chandra X-ray target-of-opportunity project designed to isolate the site of TeV flaring in the radio galaxy M87. To date, we have triggered the Chandra observations only once (2010 April) and by the time of the first of our nine observations, the TeV flare had ended. However, we found that the X-ray intensity of the unresolved nucleus was at an elevated level for our first observation. Of the more than 60 Chandra observations we have made of the M87 jet covering nine years, the nucleus was measured at a comparably high level only three times. Two of these occasions can be associated with TeV flaring, and at the time of the third event, there were no TeV monitoring activities. From the rapidity of the intensity drop of the nucleus, we infer that the size of the emitting region is of order a few light days x the unknown beaming factor; comparable to the same sort of estimate for the TeV emitting region. We also find evidence of spectral evolution in the X-ray band which seems consistent with radiative losses affecting the non-thermal population of the emitting electrons within the unresolved nucleus.

Harris, D.E.; /Harvard-Smithsonian Ctr. Astrophys.; Massaro, F.; /Harvard-Smithsonian Ctr. Astrophys. /KIPAC, Menlo Park /SLAC; Cheung, C.C.; /Natl. Acad. Sci. /Naval Research Lab, Wash., D.C.; Horns, D.; Raue, M.; /Hamburg U.; Stawarz, L.; /JAXA, Sagamihara /Jagiellonian U., Astron. Observ.; Wagner, S.; /Heidelberg Observ.; Colin, P.; /Munich, Max Planck Inst.; Mazin, D.; /Barcelona, IFAE; Wagner, R.; /Munich, Max Planck Inst.; Beilicke, M.; /McDonnell Ctr. Space Sci.; LeBohec, S.; Hui, M.; /Utah U.; Mukherjee, R.; /Barnard Coll.

2012-05-18T23:59:59.000Z

166

Synthesis, crystal and electronic structure, and physical properties of the new lanthanum copper telluride La{sub 3}Cu{sub 5}Te{sub 7}  

SciTech Connect

The new lanthanum copper telluride La{sub 3}Cu{sub 5-x}Te{sub 7} has been obtained by annealing the elements at 1073 K. Single-crystal X-ray diffraction studies revealed that the title compound crystallizes in a new structure type, space group Pnma (no. 62) with lattice dimensions of a=8.2326(3) A, b=25.9466(9) A, c=7.3402(3) A, V=1567.9(1) A{sup 3}, Z=4 for La{sub 3}Cu{sub 4.86(4)}Te{sub 7}. The structure of La{sub 3}Cu{sub 5-x}Te{sub 7} is remarkably complex. The Cu and Te atoms build up a three-dimensional covalent network. The coordination polyhedra include trigonal LaTe{sub 6} prisms, capped trigonal LaTe{sub 7} prisms, CuTe{sub 4} tetrahedra, and CuTe{sub 3} pyramids. All Cu sites exhibit deficiencies of various extents. Electrical property measurements on a sintered pellet of La{sub 3}Cu{sub 4.86}Te{sub 7} indicate that it is a p-type semiconductor in accordance with the electronic structure calculations. -- Graphical abstract: Oligomeric unit comprising interconnected CuTe{sub 3} pyramids and CuTe{sub 4} tetrahedra. Display Omitted Research highlights: {yields} La{sub 3}Cu{sub 5-x}Te{sub 7} adopts a new structure type. {yields} All Cu sites exhibit deficiencies of various extents. {yields} The coordination polyhedra include trigonal LaTe{sub 6} prisms, capped trigonal LaTe{sub 7} prisms, CuTe{sub 4} tetrahedra and CuTe{sub 3} pyramids. {yields} La{sub 3}Cu{sub 5-x}Te{sub 7} is a p-type semiconductor.

Zelinska, Mariya; Assoud, Abdeljalil [Department of Chemistry, University of Waterloo, Waterloo, ON, Canada N2L 3G1 (Canada); Kleinke, Holger, E-mail: kleinke@uwaterloo.c [Department of Chemistry, University of Waterloo, Waterloo, ON, Canada N2L 3G1 (Canada)

2011-03-15T23:59:59.000Z

167

Suzanne G.E. te Velthuis - Argonne National Laboratories, Materials Sicence  

NLE Websites -- All DOE Office Websites (Extended Search)

NXRS > Suzanne G.E. te Velthuis NXRS > Suzanne G.E. te Velthuis Suzanne G.E. te Velthuis Physicist Bldg. 223, B-205 Phone 630-252-1075 This e-mail address is being protected from spambots. You need JavaScript enabled to view it. Quick Links Selected Publications Selected Invited Talks Present Position Physicist, Materials Science Division, Argonne National Laboratory (2005-Present). Education Ph.D. Degree, Deft University of Technology, The Netherlands (1999). Masters Degree in Applied Physics, Eindhoven University of Technology, The Netherlands (1993). Professional Expirence Assistant Scientist, Materials Science Division, Argonne National Laboratory, (2001-2005). Post-doctoral Scientist, Intense Pulsed Neutron Source, Argonne National Laboratory (1999-2001). Researcher in training (leading to PhD degree), Delft University of Technology, The Netherlands (1994 -1998).

168

Hybrid model of GeV-TeV gamma ray emission from Galactic Center  

E-Print Network (OSTI)

The observations of high energy $\\gamma$-ray emission from the Galactic center (GC) by HESS, and recently by Fermi, suggest the cosmic ray acceleration in the GC and possibly around the supermassive black hole. In this work we propose a lepton-hadron hybrid model to explain simultaneously the GeV-TeV $\\gamma$-ray emission. Both electrons and hadronic cosmic rays were accelerated during the past activity of the GC. Then these particles would diffuse outwards and interact with the interstellar gas and background radiation field. The collisions between hadronic cosmic rays with gas is responsible to the TeV $\\gamma$-ray emission detected by HESS. With fast cooling in the strong radiation field, the electrons would cool down and radiate GeV photons through inverse Compton scattering off the soft background photons. This scenario provides a natural explanation of the observed GeV-TeV spectral shape of $\\gamma$-rays.

Yi-Qing Guo; Qiang Yuan; Cheng Liu; Ai-Feng Li

2013-03-26T23:59:59.000Z

169

Experimental study of double-{beta} decay modes using a CdZnTe detector array  

SciTech Connect

An array of sixteen 1 cm{sup 3} CdZnTe semiconductor detectors was operated at the Gran Sasso Underground Laboratory (LNGS) to further investigate the feasibility of double-{beta} decay searches with such devices. As one of the double-{beta} decay experiments with the highest granularity the 4x4 array accumulated an overall exposure of 18 kg days. The setup and performance of the array is described. Half-life limits for various double-{beta} decay modes of Cd, Zn, and Te isotopes are obtained. No signal has been found, but several limits beyond 10{sup 20} years have been performed. They are an order of magnitude better than those obtained with this technology before and comparable to most other experimental approaches for the isotopes under investigation. An improved limit for the {beta}{sup +}/EC decay of {sup 120}Te is given.

Dawson, J. V. [Laboratoire Astroparticule et Cosmologie, 10 rue Alice Domon et Leonie Duquet, F-75205 Paris (France); Goessling, C.; Koettig, T.; Muenstermann, D.; Rajek, S.; Schulz, O. [Lehrstuhl fuer Experimentelle Physik IV, Technische Universitaet Dortmund, Otto-Hahn Str. 4, D-44227 Dortmund (Germany); Janutta, B.; Zuber, K. [Institut fuer Kern- und Teilchenphysik, Technische Universitaet Dresden, Zellescher Weg 19, D-01069 Dresden (Germany); Junker, M. [Laboratori Nazionali del Gran Sasso, Assergi (Italy); Reeve, C. [University of Sussex, Falmer, Brighton BN1 9QH (United Kingdom); Wilson, J. R. [University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom)

2009-08-15T23:59:59.000Z

170

Experimental Realization of a Three-Dimensional Topological Insulator, Bi 2Te3  

SciTech Connect

Three-dimensional topological insulators are a new state of quantum matter with a bulk gap and odd number of relativistic Dirac fermions on the surface. By investigating the surface state of Bi{sub 2}Te{sub 3} with angle-resolved photoemission spectroscopy, we demonstrate that the surface state consists of a single nondegenerate Dirac cone. Furthermore, with appropriate hole doping, the Fermi level can be tuned to intersect only the surface states, indicating a full energy gap for the bulk states. Our results establish that Bi{sub 2}Te{sub 3} is a simple model system for the three-dimensional topological insulator with a single Dirac cone on the surface. The large bulk gap of Bi{sub 2}Te{sub 3} also points to promising potential for high-temperature spintronics applications.

Siemons, W.

2010-02-24T23:59:59.000Z

171

Energy spectrum of charge carriers in Ag{sub 2}Te  

Science Conference Proceedings (OSTI)

On the basis of investigations of the temperature and concentration dependences of kinetic coefficients (the Hall coefficientR, the electrical conductivity {sigma}, and thermopower {alpha}{sub 0}) in n-type Ag{sub 2}Te, it is established that Ag atoms in Ag{sub 2}Te create the shallow donor levels located at a distance of (0.002-7 x 10{sup -5}T) eV from the bottom of the conduction band. It is shown that silver telluride has n-type conductivity starting with the deficiency of Ag {>=} 0.01 at % in the stoichiometric composition, and it is practically impossible to achieve the stoichiometric composition in Ag{sub 2}Te.

Aliev, F. F., E-mail: farzali@physics.ab.az; Jafarov, M. B. [Academy of Sciences of Azerbaijan, Institute of Physics (Azerbaijan)

2008-11-15T23:59:59.000Z

172

Abidjan, Côte d'Ivoire: Energy Resources | Open Energy Information  

Open Energy Info (EERE)

Abidjan, Côte d'Ivoire: Energy Resources Abidjan, Côte d'Ivoire: Energy Resources Jump to: navigation, search Name Abidjan, Côte d'Ivoire Equivalent URI DBpedia GeoNames ID 2293538 Coordinates 5.341111°, -4.028056° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":5.341111,"lon":-4.028056,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

173

Advances in the In-House CdTe Research Activities at NREL  

DOE Green Energy (OSTI)

NREL in-house CdTe research activities have impacted a broad range of recent program priorities. Studies aimed at industrially relevant applications have produced new materials and processes that enhance the performance of devices based on commercial materials (e.g., soda-lime glass, SnO2:F). Preliminary tests of the effectiveness of these novel components using large-scale processes have been encouraging. Similarly, electro- and nano-probe techniques have been developed and used to study the evolution and function of CdTe grain boundaries. Finally, cathodoluminescence (CL) and photoluminescence (PL) studies on single-crystal samples have yielded improved understanding of how various processes may combine to produce important defects in CdTe films.

Gessert, T.; Wu, X.; Dhere, R.; Moutinho, H.; Smith, S.; Romero, M.; Zhou, J.; Duda, A.; Corwine, C.

2005-01-01T23:59:59.000Z

174

Spiral growth of topological insulator Sb{sub 2}Te{sub 3} nanoplates  

SciTech Connect

Sb{sub 2}Te{sub 3} nanoplates synthesized by vapor phase deposition method have been systemically investigated employing atomic force microscopy, which exhibit regular spiral structures on the surface. The height of spiral steps is determined to be 1 nm corresponding to one quintuple layer, with an inter-step separation ranging from 500 nm to 1 {mu}m. Growth mechanism of spiral structures on the Sb{sub 2}Te{sub 3} nanoplate surface is elucidated, which can be applied to other layered materials with van der Waals epitaxy growth. The electrostatic properties of Sb{sub 2}Te{sub 3} nanoplates with spiral structures are also simultaneously characterized.

Hao Guolin; Qi Xiang; Fan Yinping; Xue Lin; Peng Xiangyang; Wei Xiaolin; Zhong Jianxin [Hunan Key Laboratory for Micro-Nano Energy Materials and Devices, Xiangtan University, Hunan 411105 (China) and Laboratory for Quantum Engineering and Micro-Nano Energy Technology and Faculty of Materials and Optoelectronic Physics, Xiangtan University, Hunan 411105 (China)] [Hunan Key Laboratory for Micro-Nano Energy Materials and Devices, Xiangtan University, Hunan 411105 (China) and Laboratory for Quantum Engineering and Micro-Nano Energy Technology and Faculty of Materials and Optoelectronic Physics, Xiangtan University, Hunan 411105 (China)

2013-01-07T23:59:59.000Z

175

Dark Current Transients in Thin-Film CdTe Solar Cells: Preprint  

DOE Green Energy (OSTI)

This conference paper describes the Dark current transients measured by changing the voltage bias in a stepwise fashion on CdTe cells results in minutes-long transients after each step. Transients measured at room temperature are controlled by carrier trapping that corresponds to the well known voltage transient phenomena[1]. Transients measured on the same CdTe cell at elevated temperature (60C and 90C) show a much slower decay process. We associate this physical process with''shunt'' current paths induced with reverse bias and removed with forward bias. A different back contact process may produce an opposite voltage dependence. The lack of these transients may be required for the fabrication of ''stable'' thin-film CdTe solar cells.

McMahon, T. J.

2002-05-01T23:59:59.000Z

176

Z' Bosons, the NuTeV Anomaly, and the Higgs Boson Mass  

SciTech Connect

Fits to the precision electroweak data that include the NuTeV measurement are considered in family universal, anomaly free U(1) extensions of the Standard Model. In data sets from which the hadronic asymmetries are excluded, some of the Z{prime} models can double the predicted value of the Higgs boson mass, from {approx} 60 to {approx} 120 GeV, removing the tension with the LEP II lower bound, while also modestly improving the {chi}{sup 2} confidence level. The effect of the Z{prime} models on both m{sub H} and the {chi}{sup 2} confidence level is increased when the NuTeV measurement is included in the fit. Both the original NuTeV data and a revised estimate by the PDG are considered.

Chanowitz, Michael S

2009-03-03T23:59:59.000Z

177

Adhesion effect of interface layers on pattern fabrication with GeSbTe as laser thermal lithography film  

Science Conference Proceedings (OSTI)

Adhesion of pattern structures is a very important issue in laser thermal lithography. In this paper, Si"3N"4 and ZnS-SiO"2 were investigated as interface layers to improve patterns' adhesion to substrate on pattern fabrication with Ge"2Sb"2Te"5 as laser ... Keywords: Adhesion, GeSbTe, Interface layers, Thermal lithography, Thin films, Wet etching

Changmeng Deng; Yongyou Geng; Yiqun Wu; Yang Wang; Jinsong Wei

2013-03-01T23:59:59.000Z

178

Advances in large-area Hg1-xCdxTe photovoltaic detectors for remote-sensing applications  

Science Conference Proceedings (OSTI)

State-of-the-art large-area photovoltaic (PV) detectors fabricated in HgCdTe grown by molecular beam epitaxy (MBE) have been demonstrated for the Crosstrack Infrared Sounder (CrIS) instrument. Large-area devices (1 mm in diameter) yielded excellent electrical ... Keywords: HgCdTe, crosstrack infrared sounder, molecular beam epitaxy (MBE), photovoltaic detectors, remote sensing

P. S. Wijewarnasuriya; M. Zandian; J. Phillips; D. Edwall; R. E. Dewames; G. Hildebrandt; J. Bajaj; J. M. Arias; A. I. D'Souza; F. Moore

2002-07-01T23:59:59.000Z

179

Fabrication and characterization of CdTe nano pattern on flexible substrates by nano imprinting and electrodeposition  

Science Conference Proceedings (OSTI)

Nano imprinting technology and the electrodeposition method were applied to make CdTe nano patterns on flexible substrates. An ammonia based aqueous solution was prepared at pH 10.7 and indium tin oxide (ITO)/polyethylene naphthalate (PEN) film with ... Keywords: CdTe nano pattern, Electrodeposition, Flexible substrate, Nano imprinting

Seungju Chun; Kang-Soo Han; Ju-Hyeon Shin; Heon Lee; Donghwan Kim

2010-11-01T23:59:59.000Z

180

High efficiency thin film CdTe and a-Si based solar cells  

DOE Green Energy (OSTI)

This report describes work done by the University of Toledo during the first year of this subcontract. During this time, the CdTe group constructed a second dual magnetron sputter deposition facility; optimized reactive sputtering for ZnTe:N films to achieve 10 ohm-cm resistivity and {approximately}9% efficiency cells with a copper-free ZnTe:N/Ni contact; identified Cu-related photoluminescence features and studied their correlation with cell performance including their dependence on temperature and E-fields; studied band-tail absorption in CdS{sub x}Te{sub 1{minus}x} films at 10 K and 300 K; collaborated with the National CdTe PV Team on (1) studies of high-resistivity tin oxide (HRT) layers from ITN Energy Systems, (2) fabrication of cells on the HRT layers with 0, 300, and 800-nm CdS, and (3) preparation of ZnTe:N-based contacts on First Solar materials for stress testing; and collaborated with Brooklyn College for ellipsometry studies of CdS{sub x}Te{sub 1{minus}x} alloy films, and with the University of Buffalo/Brookhaven NSLS for synchrotron X-ray fluorescence studies of interdiffusion in CdS/CdTe bilayers. The a-Si group established a baseline for fabricating a-Si-based solar cells with single, tandem, and triple-junction structures; fabricated a-Si/a-SiGe/a-SiGe triple-junction solar cells with an initial efficiency of 9.7% during the second quarter, and 10.6% during the fourth quarter (after 1166 hours of light-soaking under 1-sun light intensity at 50 C, the 10.6% solar cells stabilized at about 9%); fabricated wide-bandgap a-Si top cells, the highest Voc achieved for the single-junction top cell was 1.02 V, and top cells with high FF (up to 74%) were fabricated routinely; fabricated high-quality narrow-bandgap a-SiGe solar cells with 8.3% efficiency; found that bandgap-graded buffer layers improve the performance (Voc and FF) of the narrow-bandgap a-SiGe bottom cells; and found that a small amount of oxygen partial pressure ({approximately}2 {times} 10{sup {minus}5} torr) was beneficial for growing high-quality films from ITO targets.

Compaan, A. D.; Deng, X.; Bohn, R. G.

2000-01-04T23:59:59.000Z

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181

ZnTe:O phosphor development for x-ray imaging applications  

Science Conference Proceedings (OSTI)

An efficient ZnTe:O x-ray powder phosphor was prepared by a dry synthesis process using gaseous doping and etching medias. The x-ray luminescent properties were evaluated and compared to standard commercial phosphors exhibited an x-ray luminescent efficiency equivalent to 76% of Gd{sub 2}O{sub 2}S:Tb and an equal resolution of 2.5 lines/mm. In addition, the fast decay time, low afterglow, and superior spectral match to conventional charge-coupled devices-indicate that ZnTe:O is a very promising phosphor candidate for x-ray imaging applications.

Kang, Z.T.; Summers, C.J.; Menkara, H.; Wagner, B.K.; Durst, R.; Diawara, Y.; Mednikova, G.; Thorson, T. [Phosphor Technology Center of Excellence, School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245 (United States); Georgia Tech Research Institute, Georgia Institute of Technology, Atlanta, Georgia 30332-0826 (United States); Bruker AXS 5465 East Cheryl Parkway, Madison Wisconson 53711 (United States)

2006-03-13T23:59:59.000Z

182

Ultrahigh Energy Cosmic Rays and Prompt TeV Gamma Rays from Gamma Ray Bursts  

E-Print Network (OSTI)

Gamma Ray Bursts (GRBs) have been proposed as one {\\it possible} class of sources of the Ultrahigh Energy Cosmic Ray (UHECR) events observed up to energies $\\gsim10^{20}\\ev$. The synchrotron radiation of the highest energy protons accelerated within the GRB source should produce gamma rays up to TeV energies. Here we briefly discuss the implications on the energetics of the GRB from the point of view of the detectability of the prompt TeV gamma rays of proton-synchrotron origin in GRBs in the up-coming ICECUBE muon detector in the south pole.

Pijushpani Bhattacharjee; Nayantara Gupta

2003-05-12T23:59:59.000Z

183

Search for heavy narrow dilepton resonances in pp collisions at $\\sqrt{s}$ = 7 TeV and $\\sqrt{s}$ = 8 TeV  

E-Print Network (OSTI)

An updated search for heavy narrow resonances decaying to muon or electron pairs using the CMS detector is presented. Data samples from pp collisions at $\\sqrt{s}$ = 7 TeV and 8 TeV at the LHC, with integrated luminosities of up to 5.3 and 4.1 inverse femtobarns, respectively, are combined. No evidence for a heavy narrow resonance is observed. The analysis of the combined data sets excludes, at 95% confidence level, a Sequential Standard Model Z'$_{SSM}$ resonance lighter than 2590 GeV, a superstring-inspired Z'$_{\\psi}$ lighter than 2260 GeV, and Kaluza-Klein gravitons lighter than 2390 (2030) GeV, assuming that the coupling parameter $k/\\bar{M}_{Pl}$ is 0.10 (0.05). These are the most stringent limits to date.

Chatrchyan, Serguei; Sirunyan, Albert M; Tumasyan, Armen; Adam, Wolfgang; Aguilo, Ernest; Bergauer, Thomas; Dragicevic, Marko; Er, Janos; Fabjan, Christian; Friedl, Markus; Fruehwirth, Rudolf; Ghete, Vasile Mihai; Hrmann, Natascha; Hrubec, Josef; Jeitler, Manfred; Kiesenhofer, Wolfgang; Knnz, Valentin; Krammer, Manfred; Krtschmer, Ilse; Liko, Dietrich; Mikulec, Ivan; Pernicka, Manfred; Rabady, Dinyar; Rahbaran, Babak; Rohringer, Christine; Rohringer, Herbert; Schfbeck, Robert; Strauss, Josef; Taurok, Anton; Waltenberger, Wolfgang; Wulz, Claudia-Elisabeth; Mossolov, Vladimir; Shumeiko, Nikolai; Suarez Gonzalez, Juan; Bansal, Monika; Bansal, Sunil; Cornelis, Tom; De Wolf, Eddi A; Janssen, Xavier; Luyckx, Sten; Mucibello, Luca; Ochesanu, Silvia; Roland, Benoit; Rougny, Romain; Selvaggi, Michele; Van Haevermaet, Hans; Van Mechelen, Pierre; Van Remortel, Nick; Van Spilbeeck, Alex; Blekman, Freya; Blyweert, Stijn; D'Hondt, Jorgen; Gonzalez Suarez, Rebeca; Kalogeropoulos, Alexis; Maes, Michael; Olbrechts, Annik; Tavernier, Stefaan; Van Doninck, Walter; Van Mulders, Petra; Van Onsem, Gerrit Patrick; Villella, Ilaria; Clerbaux, Barbara; De Lentdecker, Gilles; Dero, Vincent; Gay, Arnaud; Hreus, Tomas; Lonard, Alexandre; Marage, Pierre Edouard; Mohammadi, Abdollah; Reis, Thomas; Thomas, Laurent; Vander Velde, Catherine; Vanlaer, Pascal; Wang, Jian; Adler, Volker; Beernaert, Kelly; Cimmino, Anna; Costantini, Silvia; Garcia, Guillaume; Grunewald, Martin; Klein, Benjamin; Lellouch, Jrmie; Marinov, Andrey; Mccartin, Joseph; Ocampo Rios, Alberto Andres; Ryckbosch, Dirk; Sigamani, Michael; Strobbe, Nadja; Thyssen, Filip; Tytgat, Michael; Walsh, Sinead; Yazgan, Efe; Zaganidis, Nicolas; Basegmez, Suzan; Bruno, Giacomo; Castello, Roberto; Ceard, Ludivine; Delaere, Christophe; Du Pree, Tristan; Favart, Denis; Forthomme, Laurent; Giammanco, Andrea; Hollar, Jonathan; Lemaitre, Vincent; Liao, Junhui; Militaru, Otilia; Nuttens, Claude; Pagano, Davide; Pin, Arnaud; Piotrzkowski, Krzysztof; Vizan Garcia, Jesus Manuel; Beliy, Nikita; Caebergs, Thierry; Daubie, Evelyne; Hammad, Gregory Habib; Alves, Gilvan; Correa Martins Junior, Marcos; Martins, Thiago; Pol, Maria Elena; Henrique Gomes E Souza, Moacyr; Ald Jnior, Walter Luiz; Carvalho, Wagner; Custdio, Analu; Da Costa, Eliza Melo; De Jesus Damiao, Dilson; De Oliveira Martins, Carley; Fonseca De Souza, Sandro; Malbouisson, Helena; Malek, Magdalena; Matos Figueiredo, Diego; Mundim, Luiz; Nogima, Helio; Prado Da Silva, Wanda Lucia; Santoro, Alberto; Soares Jorge, Luana; Sznajder, Andre; Vilela Pereira, Antonio; Souza Dos Anjos, Tiago; Bernardes, Cesar Augusto; De Almeida Dias, Flavia; Tomei, Thiago; De Moraes Gregores, Eduardo; Lagana, Caio; Da Cunha Marinho, Franciole; Mercadante, Pedro G; Novaes, Sergio F; Padula, Sandra; Genchev, Vladimir; Iaydjiev, Plamen; Piperov, Stefan; Rodozov, Mircho; Stoykova, Stefka; Sultanov, Georgi; Tcholakov, Vanio; Trayanov, Rumen; Vutova, Mariana; Dimitrov, Anton; Hadjiiska, Roumyana; Kozhuharov, Venelin; Litov, Leander; Pavlov, Borislav; Petkov, Peicho; Bian, Jian-Guo; Chen, Guo-Ming; Chen, He-Sheng; Jiang, Chun-Hua; Liang, Dong; Liang, Song; Meng, Xiangwei; Tao, Junquan; Wang, Jian; Wang, Xianyou; Wang, Zheng; Xiao, Hong; Xu, Ming; Zang, Jingjing; Zhang, Zhen; Asawatangtrakuldee, Chayanit; Ban, Yong; Guo, Yifei; Li, Wenbo; Liu, Shuai; Mao, Yajun; Qian, Si-Jin; Teng, Haiyun; Wang, Dayong; Zhang, Linlin; Zou, Wei; Avila, Carlos; Carrillo Montoya, Camilo Andres; Gomez, Juan Pablo; Gomez Moreno, Bernardo; Osorio Oliveros, Andres Felipe; Sanabria, Juan Carlos; Godinovic, Nikola; Lelas, Damir; Plestina, Roko; Polic, Dunja; Puljak, Ivica; Antunovic, Zeljko; Kovac, Marko; Brigljevic, Vuko; Duric, Senka; Kadija, Kreso; Luetic, Jelena; Mekterovic, Darko; Morovic, Srecko; Tikvica, Lucija; Attikis, Alexandros; Galanti, Mario; Mavromanolakis, Georgios; Mousa, Jehad; Nicolaou, Charalambos; Ptochos, Fotios; Razis, Panos A; Finger, Miroslav; Finger Jr, Michael; Assran, Yasser; Elgammal, Sherif; Ellithi Kamel, Ali; Kuotb Awad, Alaa Metwaly; Mahmoud, Mohammed; Radi, Amr; Kadastik, Mario; Mntel, Mait; Murumaa, Marion; Raidal, Martti; Rebane, Liis; Tiko, Andres; Eerola, Paula; Fedi, Giacomo; Voutilainen, Mikko; Hrknen, Jaakko; Heikkinen, Mika Aatos; Karimki, Veikko; Kinnunen, Ritva; Kortelainen, Matti J; Lampn, Tapio; Lassila-Perini, Kati; Lehti, Sami; Lindn, Tomas; Luukka, Panja-Riina; Menp, Teppo; Peltola, Timo; Tuominen, Eija; Tuominiemi, Jorma; Tuovinen, Esa; Ungaro, Donatella; Wendland, Lauri; Korpela, Arja; Tuuva, Tuure

2013-01-01T23:59:59.000Z

184

Search for heavy narrow dilepton resonances in pp collisions at sqrt(s) = 7 TeV and sqrt(s) = 8 TeV  

E-Print Network (OSTI)

An updated search for heavy narrow resonances decaying to muon or electron pairs using the CMS detector is presented. Data samples from pp collisions at sqrt(s) = 7 TeV and 8 TeV at the LHC, with integrated luminosities of up to 5.3 and 4.1 inverse femtobarns, respectively, are combined. No evidence for a heavy narrow resonance is observed. The analysis of the combined data sets excludes, at 95% confidence level, a Sequential Standard Model Z'[SSM] resonance lighter than 2590 GeV, a superstring-inspired Z'[psi] lighter than 2260 GeV, and Kaluza-Klein gravitons lighter than 2390 (2030) GeV, assuming that the coupling parameter k/M-bar[Pl] is 0.10 (0.05). These are the most stringent limits to date.

CMS Collaboration

2012-12-26T23:59:59.000Z

185

The comprehensive phase evolution for Bi[subscript 2]Te[subscript 3] topological compound as function of pressure  

Science Conference Proceedings (OSTI)

The recently discovered three-dimensional topological insulator Bi{sub 2}Te{sub 3} is studied as function of pressure in terms of crystal structures, resistance, and Hall coefficient. The superconductivity is found in phase I (ambient phase) Bi{sub 2}Te{sub 3} with T{sub c}-3 K, which is related to the topological features. The evolution of crystal structure with pressure is investigated by high pressure synchrotron radiation experiments that reveal structural transitions occurring at about 8 GPa, 13 GPa, and 16 GPa, respectively. Furthermore, the high pressure phases of Bi{sub 2}Te{sub 3} are also superconducting but with much higher T{sub c}-8 K. The superconducting transitions are compared with those for Bi, Te elements. A global phase diagram of Bi{sub 2}Te{sub 3} as function of pressure up to 30 GPa is obtained.

Zhang, S.J.; Zhang, J.L.; Yu, X.H.; Zhu, J.; Kong, P.P.; Feng, S.M.; Liu, Q.Q.; Yang, L.X.; Wang, X.C.; Cao, L.Z.; Yang, W.G.; Wang, L.; Mao, H.K.; Zhao, Y.S.; Liu, H.Z.; Dai, X.; Fang, Z.; Zhang, S.C.; Jin, C.Q. (Stanford); (Harbin); (UST - China); (CIW); (Chinese Aca. Sci.); (LANL)

2012-06-26T23:59:59.000Z

186

Coherent optical phonon spectroscopy studies of femtosecond-laser modified Sb{sub 2}Te{sub 3} films  

Science Conference Proceedings (OSTI)

We performed time-resolved reflectivity measurements to monitor changes in optical phonon modes in Sb{sub 2}Te{sub 3} thin films under femtosecond laser irradiation. We found that a phonon mode at 3.64 THz appears after high-fluence laser irradiation, in addition to the phonon modes of Sb{sub 2}Te{sub 3}. We determined that the additional mode is due to Te segregation as a result of laser-induced decomposition of the Sb{sub 2}Te{sub 3} film. This experiment clearly illustrates the irreversible effects of femtosecond laser irradiation during the measurement of coherent optical phonon dynamics in Sb{sub 2}Te{sub 3}.

Li Yuwei; Wang Guoyu [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States); Center for Solar and Thermal Energy Conversion, University of Michigan, Michigan 48109 (United States); Stoica, Vladimir A. [Center for Solar and Thermal Energy Conversion, University of Michigan, Michigan 48109 (United States); Applied Physics Program, University of Michigan, Ann Arbor, Michigan 48109 (United States); Endicott, Lynn [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States); Uher, Ctirad; Clarke, Roy [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States); Center for Solar and Thermal Energy Conversion, University of Michigan, Michigan 48109 (United States); Applied Physics Program, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2010-10-25T23:59:59.000Z

187

Preparation and properties of evaporated CdTe films compared with single-crystal CdTe. Progress report No. 5, November 1, 1981-January 31, 1982  

DOE Green Energy (OSTI)

The hot-wall vacuum evaporator system has been put into use with successful deposition of seven thin films of n-type CdTe on glass. Microprobe analysis indicated that the films were stoichiometric CdTe. Optical transmission showed a well-defined absorption edge. Film resistivities on glass were reduced from 1.7 x 10/sup 8/ ohm-cm, to 6 x 10/sup 4/ ohm-cm by In doping; film resistivities under AM1.5 illumination are 2.0 x 10/sup 4/ and 5 x 10/sup 2/ ohm-cm, respectively compared to the dark values given above. Temperature dependence of the dark conductivity of the undoped CdTe film indicates an activation energy of 0.79 eV; in the light the activation energy was reduced to 0.1 eV. The high dark resistivity and activation energy indicate high intergrain potential barriers, which could produce the high resistivities observed even with fairly high free electron densities in the grains. Comparison will be sought between these results and those found for films deposited epitaxially on single crystal substrates. A detailed summary of absorption constant vs wavelength data for CdTe has been assembled for both single crystal and thin film materials. The absorption constant for thin film material appears to vary from 2 x 10/sup 4/ cm/sup -1/ at 8000A to 10/sup 5/ cm/sup -1/ at 5000A; single crystal values may be slightly higher. EBIC and light scanning techniques are being developed for characterizing grain boundary effects in bicrystals, and to evaluate the effects of passivation techniques. Defect densities at a grain boundary in a p-type bicrystal were found to range from 2 x 10/sup 12/ to 8 x 10/sup 12/ cm/sup -2/eV/sup -1/, using data derived from the J-V dependence of the grain boundary.

Bube, R H

1982-01-01T23:59:59.000Z

188

Sb[subscript 2]Te[subscript 3] and Bi[subscript 2]Te[subscript 3] Thin Films Grown by Room-Temperature MBE  

Science Conference Proceedings (OSTI)

Sb{sub 2}Te3 and Bi{sub 2}Te3 thin films were grown on SiO{sub 2} and BaF{sub 2} substrates at room temperature using molecular beam epitaxy. Metallic layers with thicknesses of 0.2 nm were alternately deposited at room temperature, and the films were subsequently annealed at 250 C for 2 h. x-Ray diffraction and energy-filtered transmission electron microscopy (TEM) combined with high-accuracy energy-dispersive x-ray spectrometry revealed stoichiometric films, grain sizes of less than 500 nm, and a texture. High-quality in-plane thermoelectric properties were obtained for Sb{sub 2}Te3 films at room temperature, i.e., low charge carrier density (2.6 x 10{sup 19} cm{sup -3}, large thermopower (130 {micro}V K{sup -1}), large charge carrier mobility (402 cm{sup 2} V{sup -1} s{sup -1}), and resulting large power factor (29 {micro}W cm{sup -1} K{sup -2}). Bi{sub 2}Te3 films also showed low charge carrier density (2.7 x 10{sup 19} cm{sup -3}), moderate thermopower (-153 {micro}V K{sup -1}), but very low charge carrier mobility (80 cm{sup 2} V{sup -1} s{sup -1}), yielding low power factor (8 {micro}W cm{sup -1} K{sup -2}). The low mobilities were attributed to Bi-rich grain boundary phases identified by analytical energy-filtered TEM.

Aabdin, Z.; Peranio, N.; Winkler, M.; Bessas, D.; Knig, J.; Hermann, R.P.; Bttner, H.; Eibl, O. (Julich); (Tubingen); (Fraunhofer)

2012-10-23T23:59:59.000Z

189

Overcoming degradation mechanisms in CdTe solar cells: First annual report, August 1998--August 1999  

DOE Green Energy (OSTI)

The authors have studied the importance of chemical processes for the stability of CdTe solar cells, in particular, diffusion in the ohmic contact/absorber junction regions. Both whole cells and test systems containing only the ohmic contact and the absorber are used. They found several experimental methods to be useable tools to follow the effects of impurity diffusion on the CdTe grain boundaries, grain bulk, and surface. In addition, they have explored alternative contacting schemes. The first year of activities led to the following tentative conclusions: Grain boundaries in CdTe/CdS cells are NOT fully passivated and are expected to be electrically active; There appears to be fast ionic diffusion in the vicinity of the Cu/HgTe/graphite back-contact, possibly enhanced by grain boundary diffusion; The macroscopic response to stress is different for cells with identical back-contact, but from different manufacturers. Different factors and/or different reactions to identical factors are possibly at work here; and Ni-P appears to be a promising back-contact material.

Cahen, D.; Gartsman, K.; Hodes, G.; Rotlevy, O.; Visoly-Fisher, I,; Dobson, K.

2000-02-28T23:59:59.000Z

190

Results from a search for the 0 {nu}{beta}{beta}-decay of {sup 130}Te  

SciTech Connect

A detailed description of the CUORICINO {sup 130}Te neutrinoless double-beta (0 {nu}{beta}{beta}) decay experiment is given and recent results are reported. CUORICINO is an array of 62 tellurium oxide (TeO{sub 2}) bolometers with an active mass of 40.7 kg. It is cooled to {approx}8-10 mK by a dilution refrigerator shielded from environmental radioactivity and energetic neutrons. It is running in the Laboratori Nazionali del Gran Sasso (LNGS) in Assergi, Italy. These data represent an exposure of 11.83 kg yr or 91 mole-years of {sup 130}Te. No evidence for 0 {nu}{beta}{beta}-decay was observed and a limit of T{sub 1/2}{sup 0} {sup {nu}}({sup 130}Te){>=}3.0x10{sup 24} y (90% CL) is set. This corresponds to an upper limit on the effective mass, , between 0.19 and 0.68 eV when analyzed with the many published nuclear structure calculations. In the context of these nuclear models, the values fall within the range corresponding to the claim of evidence of 0 {nu}{beta}{beta}-decay by H. V. Klapdor-Kleingrothaus et al. The experiment continues to acquire data.

Arnaboldi, C.; Brofferio, C.; Capelli, S.; Clemenza, M.; Fiorini, E.; Nucciotti, A.; Pavan, M.; Sisti, M. [Dipartimento di Fisica dell'Universita di Milano-Bicocca, I-20126 Milano (Italy); Sezione INFN di Milano-Bicocca, I-20126 Milano (Italy); Artusa, D. R.; Avignone III, F. T.; Bandac, I.; Creswick, R. J.; Farach, H. A.; Rosenfeld, C. [Department of Physics and Astronomy, University of South Carolina, Columbia, SC 29208 (United States); Balata, M.; Bucci, C.; Giachero, A.; Gorla, P.; Nisi, S. [INFN Laboratori Nazionali del Gran Sasso, I-67010, Assergi (L'Aquila) (Italy); Barucci, M. [Dipartimento di Fisica dell'Universita di Firenze, I-50019 Firenze (Italy); Sezione INFN di Firenze, I-50019, Firenze (Italy)] (and others)

2008-09-15T23:59:59.000Z

191

Physical properties of Ce3-xTe4 below room temperature  

Science Conference Proceedings (OSTI)

The physical properties of polycrystalline Ce{sub 3-x}Te{sub 4} were investigated by measurements of the thermoelectric properties, Hall coefficient, heat capacity, and magnetization. The fully filled, metallic x = 0 compound displays a soft ferromagnetic transition near 4 K, and analysis of the corresponding heat capacity anomaly suggests a doublet ground state for Ce{sup 3+}. The transition is suppressed to below 2 K in the insulating x = 0.33 composition, revealing that magnetic order in Ce{sub 3-x}Te{sub 4} is driven by a Ruderman-Kittel-Kasuya-Yosida (RKKY)-type interaction. The thermoelectric properties trend with composition as expected from simple electron counting, and the transport properties in Ce{sub 3}Te{sub 4} are observed to be similar to those in La{sub 3}Te{sub 4}. Trends in the low-temperature thermal conductivity data reveal that the phonons are efficiently scattered by electrons, while all compositions examined have a lattice thermal conductivity near 1.2 W/m K{sup -1} at 200 K.

May, Andrew F [ORNL; McGuire, Michael A [ORNL; Cantoni, Claudia [ORNL; Sales, Brian C [ORNL

2012-01-01T23:59:59.000Z

192

Degradation and Capacitance-Voltage Hysteresis in CdTe Devices: Preprint  

DOE Green Energy (OSTI)

CdS/CdTe cells on CTO/ZTO TCO show greater intial performance than SnO2-gased substrates due to superior optical and electrical properties of the oxide layers and more rigorous CdCl2 processing. Performance unfiormity was a problem.

Albin, D. S.; Dhere, R. G.; Glynn, S. C.; DelCueto, J.; Metzger W. K.

2009-07-01T23:59:59.000Z

193

p-Doping limit and donor compensation in CdTe polycrystalline thin film solar cells  

E-Print Network (OSTI)

everything accelerates. ARCO solar produces more than 1 MW PV cells in `80, being the first in the world, the Million Solar Roofs in the US, and many more. Besides these programs, the efficiency of CdTe thin film PV energy source is the photovoltaic (PV) cell, which converts sunlight to electrical current, without any

Bieber, Michael

194

Room-temperature oxygen sensitization in highly textured, nanocrystalline PbTe films: A mechanistic study  

E-Print Network (OSTI)

In this paper, we report large mid-wave infrared photoconductivity in highly textured, nanocrystalline PbTe films thermally evaporated on Si at room temperature. Responsivity as high as 25 V/W is measured at the 3.5 ?m ...

Wang, Jianfei

195

Appendix B: CArBon dioxide CApture teChnology SheetS  

NLE Websites -- All DOE Office Websites (Extended Search)

B-54 Pre-Combustion membranes u.s. DePartment of energy aDvanCeD Carbon DioxiDe CaPture r&D Program: teChnology uPDate, may 2013 aDvanCeD hyDrogen transPort membranes for Coal...

196

Search for supersymmetric charged Higgs bosons at the TeVatron  

SciTech Connect

The data collected at the TeVatron RunIIa have been used to look for supersymmetric charged Higgs boson and Left-Right suspersymmetric doubly charged Higgs boson. No signal of such bosons has been found and this note reports on the current analyses and their observed excluded domains in models parameter space.

Grenier, Gerald; /Lyon, IPN

2007-10-01T23:59:59.000Z

197

Search for supersymmetric charged Higgs bosons at the TeVatron  

E-Print Network (OSTI)

The data collected at the TeVatron RunIIa have been used to look for supersymmetric charged Higgs boson and Left-Right suspersymmetric doubly charged Higgs boson. No signal of such bosons has been found and this note reports on the current analyses and their observed excluded domains in models parameter space.

Gerald Grenier

2007-10-03T23:59:59.000Z

198

Search for supersymmetric charged Higgs bosons at the TeVatron  

E-Print Network (OSTI)

The data collected at the TeVatron RunIIa have been used to look for supersymmetric charged Higgs boson and Left-Right suspersymmetric doubly charged Higgs boson. No signal of such bosons has been found and this note reports on the current analyses and their observed excluded domains in models parameter space.

Grenier, Gerald

2007-01-01T23:59:59.000Z

199

Accelerated Stress Testing and Diagnostic Analysis of Degradation in CdTe Solar Cells  

DOE Green Energy (OSTI)

The primary goal of this study was to ascertain the presence and types of mechanisms affecting CdS/CdTe device stability in the temperature range of 60 to 120 ..deg..C. It should be noted that the results presented were specific to cells made using the specific growth conditions described.

Albin, D. S.

2008-11-01T23:59:59.000Z

200

Comparison of Minority Carrier Lifetime Measurements in Superstrate and Substrate CdTe PV Devices: Preprint  

DOE Green Energy (OSTI)

We discuss typical and alternative procedures to analyze time-resolved photoluminescence (TRPL) measurements of minority carrier lifetime (MCL) with the hope of enhancing our understanding of how this technique may be used to better analyze CdTe photovoltaic (PV) device functionality. Historically, TRPL measurements of the fast recombination rate (t1) have provided insightful correlation with broad device functionality. However, we have more recently found that t1 does not correlate as well with smaller changes in device performance, nor does it correlate well with performance differences observed between superstrate and substrate CdTe PV devices. This study presents TRPL data for both superstrate and substrate CdTe devices where both t1 and the slower TRPL decay (t2) are analyzed. The study shows that changes in performance expected from small changes in device processing may correlate better with t2. Numerical modeling further suggests that, for devices that are expected to have similar drift field in the depletion region, effects of changes in bulk MCL and interface recombination should be more pronounced in t2. Although this technique may provide future guidance to improving CdS/CdTe device performance, it is often difficult to extract statistically precise values for t2, and therefore t2 data may demonstrate significant scatter when correlated with performance parameters.

Gessert, T. A.; Dhere, R. G.; Duenow, J. N.; Kuciauskas, D.; Kanevce, A.; Bergeson, J. D.

2011-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "graphi te hoback" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Higgs Coupling Measurements at a 1 TeV Linear Collider  

SciTech Connect

Methods for extracting Higgs boson signals at a 1 TeV center-of-mass energy e{sup +}e{sup -} linear collider are described. In addition, estimates are given for the accuracy with which branching fractions can be measured for Higgs boson decays to b{bar b} WW, gg, and {gamma}{gamma}.

Barklow, T

2003-12-18T23:59:59.000Z

202

PyR@TE: Renormalization Group Equations for General Gauge Theories  

E-Print Network (OSTI)

Although the two-loop renormalization group equations for a general gauge field theory have been known for quite some time, deriving them for specific models has often been difficult in practice. This is mainly due to the fact that, albeit straightforward, the involved calculations are quite long, tedious and prone to error. The present work is an attempt to facilitate the practical use of the renormalization group equations in model building. To that end, we have developed two completely independent sets of programs written in Python and Mathematica, respectively. The Mathematica scripts will be part of an upcoming release of SARAH 4. The present article describes the collection of Python routines that we dubbed PyR@TE which is an acronym for "Python Renormalization group equations At Two-loop for Everyone". In PyR@TE, once the user specifies the gauge group and the particle content of the model, the routines automatically generate the full two-loop renormalization group equations for all (dimensionless and dimensionful) parameters. The results can optionally be exported to Latex and Mathematica, or stored in a Python data structure for further processing by other programs. For ease of use, we have implemented an interactive mode for PyR@TE in form of an IPython Notebook. As a first application, we have generated with PyR@TE the renormalization group equations for several non-supersymmetric extensions of the Standard Model and found some discrepancies with the existing literature.

Florian Lyonnet; Ingo Schienbein; Florian Staub; Akin Wingerter

2013-09-26T23:59:59.000Z

203

Appendix B: CArBon dioxide CApture teChnology SheetS  

NLE Websites -- All DOE Office Websites (Extended Search)

solvents B-6 Pre-Combustion solvents u.s. DePartment of energy aDvanCeD Carbon DioxiDe CaPture r&D Program: teChnology uPDate, may 2013 Co 2 CaPture from igCC gas streams using...

204

Spray Deposition of High Quality CuInSe2 and CdTe Films: Preprint  

DOE Green Energy (OSTI)

A number of different ink and deposition approaches have been used for the deposition of CuInSe2 (CIS), Cu(In,Ga)Se2 (CIGS), and CdTe films. For CIS and CIGS, soluble precursors containing Cu, In, and Ga have been developed and used in two ways to produce CIS films. In the first, In-containing precursor films were sprayed on Mo-coated glass substrates and converted by rapid thermal processing (RTP) to In2Se3. Then a Cu-containing film was sprayed down on top of the In2Se3 and the stacked films were again thermally processed to give CIS. In the second approach, the Cu-, In-, and Ga-containing inks were combined in the proper ratio to produce a mixed Cu-In-Ga ink that was sprayed on substrates and thermally processed to give CIGS films directly. For CdTe deposition, ink consisting of CdTe nanoparticles dispersed in methanol was prepared and used to spray precursor films. Annealing these precursor films in the presence of CdCl2 produced large-grained CdTe films. The films were characterized by x-ray diffraction (XRD) and scanning electron microscopy (SEM). Optimized spray and processing conditions are crucial to obtain dense, crystalline films.

Curtis, C. J.; van Hest, M.; Miedaner, A.; Leisch, J.; Hersh, P.; Nekuda, J.; Ginley, D. S.

2008-05-01T23:59:59.000Z

205

Design and Test of a 100MW X Band TE01 Window  

Science Conference Proceedings (OSTI)

Research at Stanford Linear Accelerator Center (SLAC) is in progress on a TeV-scale linear collider that will operate at 5-10 times the energy of present generation accelerators. This will require development of high power X-Band sources generating 50-100 MW per source. Conventional pillbox window designs are capable of transmitting peak rf powers up to about 30 MW, well below the desired level required for the use of a single window per tube. SLAC has developed a 75 MW TE{sub 01} window [1] that uses a 'traveling wave' design to minimize fields at the window face. Irises match to the dielectric window impedance, resulting in a pure traveling wave in the ceramic and minimum fields on the window face. The use of the TE{sub 01} mode also has zero electric field on the braze fillet. Unfortunately, in-band resonances prevented this window design from achieving the desired 75MW power level. It was believed the resonances resulted from sudden steps in the circular guide to match the 38mm input diameter to the overmoded (TE{sub 01} and TE{sub 02} mode propagating) 65 mm diameter of the window ceramic. Calabazas Creek Research Inc. is currently developing a traveling wave window using compact, numerically optimized, parabolic tapers to match the input diameter of 38mm to the window ceramic diameter of 76mm (Figure 1). The design is projected to handle 100 MW of pulse power with a peak field at the window face of 3.6 MV/m. Cold test of the window has shown the return loss to be better than -25 dB over a 100 MHz bandwidth and to be resonance free (Figure 2). The window is scheduled for high-power testing in July 2003 at the SLAC.

Neilson, J.; Ives, L.; Tantawi, S.G.; /Calabazas Creek Res., Saratoga /SLAC

2008-03-24T23:59:59.000Z

206

Novel ways of depositing ZnTe films by a solution growth technique. Final subcontract report, 1 January 1990--1 January 1992  

DOE Green Energy (OSTI)

An electrochemical process has been successfully developed for the reproducible deposition of ZnTe and copper-doped ZnTe films suitable as transparent ohmic contacts for CdS/CdTe solar cells. The development of this method and optimization of key processing steps in the fabrication of CdS/CdTe/ZnTe:Cu devices has allowed IEC to achieve cell performance results of FF>70% and {eta} {approximately}10%. Preliminary efforts have indicated that the deposition methods investigated are potentially feasible for the formation of other II-VI compounds for use in polycrystalline thin film solar devices and should be the focus of future work.

Birkmire, R.W.; McCandless, B.E.; Yokimcus, T.A.; Mondal, A. [Delaware Univ., Newark, DE (United States). Inst. of Energy Conversion

1992-10-01T23:59:59.000Z

207

Band offsets for mismatched interfaces: The special case of ZnO on CdTe (001)  

SciTech Connect

High-quality planar interfaces between ZnO and CdTe would be useful in optoelectronic applications, but appear difficult to achieve given the rather different crystal structures (CdTe is zinc blende with cubic lattice constant a = 6.482 , ZnO is hexagonal wurtzite with a = 3.253 and c = 5.213 .) However, ZnO has been reported to occur in some epitaxially stabilized films in the zinc blende structure with an fcc primitive lattice constant close to the hexagonal a value. Observing that this value equals half of the CdTe cubic lattice constant to within 1%, we propose that (001)-oriented cubic ZnO films could be grown epitaxially on a CdTe (001) surface in an R45 ?2??2 configuration. Many terminations and alignments (in-plane fractional translations) are possible, and we describe density-functional total-energy electronic-structure calculations on several configurations to identify the most likely form of the interface, and to predict valence-band offsets between CdTe and ZnO in each case. Growth of ZnO on Te-terminated CdTe (001) is predicted to produce small or even negative (CdTe below ZnO) valence band offsets, resulting in a Type I band alignment. Growth on Cd-terminated CdTe is predicted to produce large positive offsets for a type II alignment as needed, for example, in solar cells. We also describe recent experiments that corroborate some of these predictions.

Jaffe, John E.; Kaspar, Tiffany C.; Droubay, Timothy; Varga, Tamas

2013-08-02T23:59:59.000Z

208

Syntheses, crystal structures, and characterization of two new Tl{sup +}-Cu{sup 2+}-Te{sup 6+} oxides: Tl{sub 4}CuTeO{sub 6} and Tl{sub 6}CuTe{sub 2}O{sub 10}  

SciTech Connect

Crystals and polycrystalline powders of two new oxide materials, Tl{sub 4}CuTeO{sub 6} and Tl{sub 6}CuTe{sub 2}O{sub 10}, have been synthesized by hydrothermal and solid-state methods. The materials were structurally characterized by single-crystal X-ray diffraction. Tl{sub 4}CuTeO{sub 6} and Tl{sub 6}CuTe{sub 2}O{sub 10} exhibit one dimensional anionic slabs of [CuTeO{sub 6}]{sup 4-} and [CuTe{sub 2}O{sub 10}]{sup 6-}, respectively. Common to both slabs is the occurrence of Cu{sup 2+}O{sub 4} distorted squares and Te{sup 6+}O{sub 6} octahedra. The slabs are separated by Tl{sup +} cations. For Tl{sub 4}CuTeO{sub 6}, magnetic measurements indicate a maximum at {approx}8 K in the temperature dependence of the susceptibility. Low temperature neutron diffraction data confirm no long-range magnetic ordering occurs and the susceptibility was adequately accounted for by fits to a Heisenberg alternating chain model. For Tl{sub 6}CuTe{sub 2}O{sub 10} on the other hand, magnetic measurements revealed paramagnetism with no evidence of long-range magnetic ordering. Infrared, UV-vis spectra, thermogravimetric, and differential thermal analyses are also reported. Crystal data: Tl{sub 4}CuTeO{sub 6}, Triclinic, space group P-1 (No. 2), a=5.8629(8) A, b=8.7848(11) A, c=9.2572(12) A, {alpha}=66.0460(10), {beta}=74.2010(10), {gamma}=79.254(2), V=417.70(9) A{sup 3}, and Z=2; Tl{sub 6}CuTe{sub 2}O{sub 10}, orthorhombic, space group Pnma (No. 62), a=10.8628(6) A, b=11.4962(7) A, c=10.7238(6) A, V=1339.20(13) A{sup 3}, and Z=4. - Graphical Abstract: Two new oxide materials, Tl{sub 4}CuTeO{sub 6} and Tl{sub 6}CuTe{sub 2}O{sub 10}, have been synthesized and characterized. The materials exhibit one dimensional crystal structures consisting of CuO{sub 4} and TeO{sub 6} polyhedra. Highlights: Black-Right-Pointing-Pointer Two New Tl-Te-Cu-oxides have been synthesized and structurally characterized. Black-Right-Pointing-Pointer For Tl{sub 4}CuTeO{sub 6}, magnetic measurements indicate a maximum at {approx}8 K. Black-Right-Pointing-Pointer Low temperature neutron diffraction data confirm no long-range magnetic ordering. Black-Right-Pointing-Pointer For Tl{sub 6}CuTe{sub 2}O{sub 10} magnetic measurements revealed no long-range magnetic ordering.

Yeon, Jeongho; Kim, Sang-Hwan [Department of Chemistry, University of Houston, 136 Fleming Building, Houston, TX 77204-5003 (United States)] [Department of Chemistry, University of Houston, 136 Fleming Building, Houston, TX 77204-5003 (United States); Green, Mark A. [Department of Materials Science and Engineering, University of Maryland, College Park, MD, 20742-2115 and NIST Center for Neutron Research, National Institute of Standard and Technology, 100 Bureau Drive, Gaithersburg, MD 20899-6103 (United States)] [Department of Materials Science and Engineering, University of Maryland, College Park, MD, 20742-2115 and NIST Center for Neutron Research, National Institute of Standard and Technology, 100 Bureau Drive, Gaithersburg, MD 20899-6103 (United States); Bhatti, Kanwal Preet; Leighton, C. [Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455-0132 (United States)] [Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455-0132 (United States); Shiv Halasyamani, P., E-mail: psh@uh.edu [Department of Chemistry, University of Houston, 136 Fleming Building, Houston, TX 77204-5003 (United States)

2012-12-15T23:59:59.000Z

209

Direct Correlation of CdTe Solar Cell Stabiity with Mobile Ion Charge Generation During Accelerated Lifetime Testing: Preprint  

DOE Green Energy (OSTI)

CdS/CdTe cells deposited on CTO/ZTO TCO substrates show greater degradation than similar devices fabricated on cSnO2/iSnO2 substrates.

Albin, D. S.; Dhere, R. G.; Glynn, S. C.; Metzger, W. K.

2009-06-01T23:59:59.000Z

210

On 30 November, energy record for the LHC, twin beams at 1.18 TeV  

E-Print Network (OSTI)

Soon after midnight on November 30 the LHC beats its new world record with two beams ramped to 1.18 TeV simultaneously. The beams were dumped 45 minutes later.

CERN Photo Service

2009-01-01T23:59:59.000Z

211

Expanding the Limits of CdTe PV Performance: Phase I Annual Report, 7 February 2006 - 30 June 2007  

DOE Green Energy (OSTI)

First Solar made 9 CdTe PV devices; found two front- and one back-side structures that show improved Jsc and Voc, respectively, compared to base device structure; best cell efficiency was 14.13%.

Meyers, P.

2007-12-01T23:59:59.000Z

212

CdSe/CdTe type-II superlattices grown on GaSb (001) substrates by molecular beam epitaxy  

SciTech Connect

CdSe/CdTe superlattices are grown on GaSb substrates using molecular beam epitaxy. X-ray diffraction measurements and cross-sectional transmission electron microscopy images indicate high crystalline quality. Photoluminescence (PL) measurements show the effective bandgap varies with the superlattice layer thicknesses and confirm the CdSe/CdTe heterostructure has a type-II band edge alignment. The valence band offset between unstrained CdTe and CdSe is determined as 0.63 {+-} 0.06 eV by fitting the measured PL peak positions using the envelope function approximation and the Kronig-Penney model. These results suggest that CdSe/CdTe superlattices are promising candidates for multi-junction solar cells and other optoelectronic devices based on GaSb substrates.

Li Jingjing; Liu Shi; Wang Shumin; Ding Ding; Johnson, Shane R.; Zhang Yonghang [Center for Photonics Innovation, Arizona State University, Tempe, Arizona 85287 (United States); School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287 (United States); Liu Xinyu; Furdyna, Jacek K. [Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Smith, David J. [Center for Photonics Innovation, Arizona State University, Tempe, Arizona 85287 (United States); Department of Physics, Arizona State University, Tempe, Arizona 85287 (United States)

2012-03-19T23:59:59.000Z

213

High efficiency thin film CdTe solar cells. Second quarterly progress report, June 19-September 18, 1979  

DOE Green Energy (OSTI)

During the second quarter of this program primary emphasis was put into depositing and evaluating both n and p-type CdTe films on a variety of conducting and non-conducting substrates. Improvements in the deposition apparatus permitted preparation of a large number of CdTe films and numerous analytic techniques available at Tufts University were utilized to examine these films. It was found that the introduction of a thin (100 A). In layer between the ITO and the CdTe significantly reduced the previously observed barrier present at the ITO/n-CdTe interface without adversely reducing optical transmission. While the resistivity of the films is still rather high, very recent results show that proper changes in procedure are capable of markedly lowering the resistivity. Preliminary Schottky barrier devices have been made which show promising photovoltaic characteristics.

Serreze, H.B.; Entine, G.; Goldner, R.B.

1979-10-01T23:59:59.000Z

214

Measurement of the W+W- Cross Section in ?s=7??TeV pp Collisions with ATLAS  

E-Print Network (OSTI)

This Letter presents a measurement of the W[superscript +]W[superscript -] production cross section in ?s=7??TeV pp collisions by the ATLAS experiment, using 34??pb[superscript -1] of integrated luminosity produced by the ...

Taylor, Frank E.

215

Modeling Cu Migration in CdTe Solar Cells Under Device-Processing and Long-Term Stability Conditions (Poster)  

DOE Green Energy (OSTI)

An impurity migration model for systems with material interfaces is applied to Cu migration in CdTe solar cells. In the model, diffusion fluxes are calculated from the Cu chemical potential gradient. Inputs to the model include Cu diffusivities, solubilities, and segregation enthalpies in CdTe, CdS and contact materials. The model yields transient and equilibrium Cu distributions in CdTe devices during device processing and under field-deployed conditions. Preliminary results for Cu migration in CdTe PV devices using available diffusivity and solubility data from the literature show that Cu segregates in the CdS, a phenomenon that is commonly observed in devices after back-contact processing and/or stress conditions.

Teeter, G.; Asher, S.

2008-05-01T23:59:59.000Z

216

Disordered stoichiometric nanorods and ordered off-stoichiometric nanoparticles in n-type thermoelectric Bi?Te?.?Se?.?  

E-Print Network (OSTI)

N-type Bi?Te?.?Se?.? bulk thermoelectric materials with peak ZT values up to ?1 were examined by transmission electron microscopy and electron diffraction. Two nanostructural features were found: (i) a structural modulation ...

Carlton, Chris E.

217

Low cost sprayed CdTe solar cell research. Second quarterly report, November 15, 1979-February 14, 1980  

DOE Green Energy (OSTI)

A comprehensive series of experiments was performed with the aim of optimizing parameters in the chemical spray deposition (CSD) of CdTe thin films. Two approaches have shown great promise. X-ray diffraction analysis has shown that CdTe can be produced from solutions containing CdCl/sub 2/ and (NH/sub 4/)TeO/sub 4/ with either hydrazine dihydrochloride or oxalic acid as the reducing agent. Films produced from the oxalic acid experiments have yielded encouraging infrared scans, and as a result this approach has received the most effort. In addition, good quality, photoconductive, CdS films have been produced via traditional methods and characterized using optical and electrical measurements. Overall film uniformity for both CdS and CdTe has been improved by the installation of a stainless steel, gravity fed, spray nozzle and mechanical linkage.

Sienkiewicz, P.; Lis, S.; Serreze, H.B.; Entine, G.

1980-03-01T23:59:59.000Z

218

Thin Metal Oxide Films to Modify a Window Layer in CdTe-Based Solar Cells for Improved Performance  

Science Conference Proceedings (OSTI)

We report on CdS/CdTe photovoltaic devices that contain a thin Ta2O5 film deposited onto the CdS window layer by sputtering. We show that for thicknesses below 5 nm, Ta2O5 films between CdS and CdTe positively affect the solar cell performance, improving JSC, VOC, and the cell power conversion efficiency despite the insulating nature of the interlayer material. Using the Ta2O5 interlayer, a VOC gain of over 100 mV was demonstrated compared to a CdTe/CdS baseline. Application of a 1nm Ta2O5 interlayer enabled the fabrication of CdTe solar cells with extremely thin (less than 30 nm) CdS window layers. The efficiency of these cells exceeded that of a base line cell with 95 nm of CdS.

Lemmon, John P.; Polikarpov, Evgueni; Bennett, Wendy D.; Kovarik, Libor

2012-05-05T23:59:59.000Z

219

Performance improvement of Ge-Sb-Te material by GaSb doping for phase change memory  

SciTech Connect

Effects of GaSb doping on phase change characteristics of Ge-Sb-Te material are investigated by in situ resistance and x-ray diffraction measurement, optical spectroscopy, and x-ray photoelectron spectroscopy. The crystallization temperature and data retention of Ge-Sb-Te material increase significantly by the addition of GaSb, which results from the high thermal stability of amorphous GaSb. In addition, GaSb-doped Ge-Sb-Te material exhibits faster crystallization speed due to the change in electronic states as a result of the formation of chemical bonds with Ga element. Incorporation of GaSb is highly effective way to enhance the comprehensive performance of Ge-Sb-Te material for phase change memory.

Lu, Yegang [State Key Laboratory of Functional Materials for Informatics, Laboratory of Nanotechnology, Shanghai Institute of Micro-system and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China) [State Key Laboratory of Functional Materials for Informatics, Laboratory of Nanotechnology, Shanghai Institute of Micro-system and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Faculty of Information Science and Engineering, Ningbo University, Ningbo 315211 (China); Graduate School of Chinese Academy of Sciences, Beijing 100049 (China); Zhang, Zhonghua; Song, Sannian; Cheng, Limin; Song, Zhitang [State Key Laboratory of Functional Materials for Informatics, Laboratory of Nanotechnology, Shanghai Institute of Micro-system and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China)] [State Key Laboratory of Functional Materials for Informatics, Laboratory of Nanotechnology, Shanghai Institute of Micro-system and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Shen, Xiang; Wang, Guoxiang; Dai, Shixun [Faculty of Information Science and Engineering, Ningbo University, Ningbo 315211 (China)] [Faculty of Information Science and Engineering, Ningbo University, Ningbo 315211 (China)

2013-06-17T23:59:59.000Z

220

Modeling Cu Migration in CdTe Solar Cells Under Device-Processing and Long-Term Stability Conditions: Preprint  

DOE Green Energy (OSTI)

An impurity migration model for systems with material interfaces is applied to Cu migration in CdTe solar cells. In the model, diffusion fluxes are calculated from the Cu chemical potential gradient. Inputs to the model include Cu diffusivities, solubilities, and segregation enthalpies in CdTe, CdS and contact materials. The model yields transient and equilibrium Cu distributions in CdTe devices during device processing and under field-deployed conditions. Preliminary results for Cu migration in CdTe photovoltaic devices using available diffusivity and solubility data from the literature show that Cu segregates in the CdS, a phenomenon that is commonly observed in devices after back-contact processing and/or stress conditions.

Teeter, G.; Asher, S.

2008-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "graphi te hoback" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Correlations of Capacitance-Voltage Hysteresis with Thin-Film CdTe Solar Cell Performance During Accelerated Lifetime Testing  

SciTech Connect

In this paper we present the correlation of CdTe solar cell performance with capacitance-voltage hysteresis, defined presently as the difference in capacitance measured at zero-volt bias when collecting such data with different pre-measurement bias conditions. These correlations were obtained on CdTe cells stressed under conditions of 1-sun illumination, open-circuit bias, and an acceleration temperature of approximately 100 degrees C.

Albin, D.; del Cueto, J.

2011-03-01T23:59:59.000Z

222

EGS4 calculations for a Cd-Zn-Te detector to measure synchrotron radiation at PEP-II  

SciTech Connect

Calculations have been performed with the EGS4 Code System for a CdZnTe semiconductor detector to be used in background studies of synchrotron radiation at PEP-II. The simulations take into account K-shell fluorescent-photon production in a CdZnTe mixture, electron-hole pair collection and electronic-noise broadening. The results are compared with measurements made with encapsulated {sup 241}Am, {sup 133}Ba and {sup 109}Cd sources.

Nelson, W.R. [Stanford Univ., CA (US). Stanford Linear Accelerator Center; Borak, T.; Malchow, R.; Toki, W. [Colorado State Univ., Fort Collins, CO (US); Kadyk, J. [Lawrence Berkeley National Lab., CA (US)

1997-08-20T23:59:59.000Z

223

EGS4 CALCULATIONS FOR A Cd-Zn-Te DETECTOR TO? y MEASURE SYNCHROTRON RADIATION AT PEP-II  

E-Print Network (OSTI)

Calculations have been performed with the EGS4 Code System for a CdZnTe semiconductor detector to be used in background studies of synchrotron radiation at PEP-II. The simulations take into account K-shell uorescent-photon production in a CdZnTe mixture, electron-hole pair collection and electronic-noise broadening. The results are compared with measurements made with encapsulated 241 Am, 133 Ba and 109 Cd sources.

W. R. Nelson; T. Borak; R. Malchow; W. Toki; J. Kadyk

1997-01-01T23:59:59.000Z

224

Process Development for High Voc CdTe Solar Cells: Phase I, Annual Technical Report, October 2005 - September 2006  

DOE Green Energy (OSTI)

The focus of this project is the open-circuit voltage of the CdTe thin-film solar cell. CdTe continues to be one of the leading materials for large-scale cost-effective production of photovoltaics, but the efficiency of the CdTe solar cell has been stagnant for the last few years. At the manufacturing front, the CdTe technology is fast paced and moving forward with U.S.-based First Solar LLC leading the world in CdTe module production. To support the industry efforts and continue the advancement of this technology, it will be necessary to continue improvements in solar cell efficiency. A closer look at the state-of-the-art performance levels puts the three solar cell efficiency parameters of short-circuit current density (JSC), open-circuit voltage (VOC), and fill factor (FF) in the 24-26 mA/cm2, 844?850 mV, and 74%-76% ranges respectively. During the late 1090s, efforts to improve cell efficiency were primarily concerned with increasing JSC, simply by using thinner CdS window layers to enhance the blue response (<510 nm) of the CdTe cell. These efforts led to underscoring the important role 'buffers' (or high-resistivity transparent films) play in CdTe cells. The use of transparent bi-layers (low-p/high-p) as the front contact is becoming a 'standard' feature of the CdTe cell.

Ferekides, C. S.; Morel, D. L.

2007-04-01T23:59:59.000Z

225

Search for new particles decaying to diject in 7 TeV proton-proton collisions at CMS  

SciTech Connect

This thesis presents a measurement of the dijet invariant mass spectrum and search for new particles decaying to dijets at CMS in 7 TeV pp collisions using data corresponding to an integrated luminosity of 2.875 pb{sup -1}. The measured dijet mass distribution is compared to QCD prediction from PYTHIA . It is required the pseudorapidity separation of the two jets to satisfy |Dh| < 1.3 with each jet inside the region of |{eta}| < 2.5. The observed dijet mass spectrum is fitted by a smooth function to search for dijet resonances. Since there is no evidence for dijet resonances, the upper limits at 95% Confidence Level (C.L.) on the resonance cross section are set. These generic cross section limits are compared with theoretical predictions for the cross section for several models of new particles: string resonances, axigluons, colorons, excited quarks, E{sub 6} diquarks, Randall-Sundrum gravitons, W' and Z'. It is excluded at 95% C.L. string resonances in the mass range 0.50 < M(S) < 2.50 TeV, excited quarks in the mass range 0.50 < M(q*) < 1.58 TeV, axigluons and colorons in the mass ranges 0.50 < M(A) < 1.17 TeV and 1.47 < M(A) < 1.52 TeV, and E{sub 6} diquarks in the mass ranges 0.50 < M(D) < 0.58 TeV, 0.97 < M(D) < 1.08 TeV, and 1.45 < M(D) < 1.60 TeV. These exclusions extend previously published limits on all models.

Ozturk, Sertac; /Cukurova U.

2011-03-01T23:59:59.000Z

226

Glass-like phonon scattering from a spontaneous nanostructure in AgSbTe2  

Science Conference Proceedings (OSTI)

Materials with very low thermal conductivity are of high interest for both thermoelectric and optical phase-change applications. Synthetic nanostructuring is most promising to suppress thermal conductivity by scattering phonons, but challenges remain in producing bulk samples. We show that in crystalline AgSbTe2, a spontaneously-forming nanostructure leads to a suppression of thermal conductivity to a glass-like level. Our mappings of phonon mean-free-paths provide a novel bottom- up microscopic account of thermal conductivity, and also reveal intrinsic anisotropies associated with the nanostructure. Ground-state degeneracy in AgSbTe2 leads to the natural formation of nanoscale domains with different orderings on the cation sublattice, and correlated atomic displacements, which efficiently scatter phonons. This mechanism is general and points to a new avenue in nano- scale engineering of materials, to achieve low thermal conductivities for efficient thermoelectric converters and phase-change memory devices.

Abernathy, Douglas L [ORNL; Ehlers, Georg [ORNL; Huq, Ashfia [ORNL; Ma, Jie [ORNL; May, Andrew F [ORNL; McGuire, Michael A [ORNL; Sales, Brian C [ORNL; Delaire, Olivier A [ORNL; Hong, Tao [ORNL; Tian, Wei [ORNL

2013-01-01T23:59:59.000Z

227

Appendix B: CArBon dioxide CApture teChnology SheetS  

NLE Websites -- All DOE Office Websites (Extended Search)

sorbents sorbents B-14 Pre-Combustion sorbents u.s. DePartment of energy aDvanCeD Carbon DioxiDe CaPture r&D Program: teChnology uPDate, may 2013 aDvanCeD Carbon DioxiDe CaPture teChnology for low-rank Coal integrateD gasifiCation CombineD CyCle (igCC) systems primary project goals TDA will investigate the technical and economic advantages of using an integrated carbon dioxide (CO 2 ) sorbent and water-gas shift (WGS) catalyst system in an integrated gasifi- cation combined cycle (IGCC) power plant, fueled with low-rank coal, and designed to capture more than 90% of the CO 2 emissions. technical goals * TDA will evaluate the physical mix of the sorbent and catalyst pellets within the same

228

EE&RE, Session: CdTe - Progress and Roadmap Alignment (Presentation)  

DOE Green Energy (OSTI)

This project supports the Solar America Initiative by: (1) assistance to SAI Incubators (Primestar Solar, AvA Solar); (2) providing industry with baseline understanding of CdS/CdTe device formation and reliability--incorporation of low-cost, high quality TCOs, functionality and options for buffer layers, effect of various CdS options, effect of and importance CdSTe alloy formation, effect and options for CdCl{sub 2} treatment, effect and options for back contact, and effect of residual impurities during all stages of device formation; (3) understanding modes and mechanisms of cell-level stability; and (4) establishment of CdTe PDIL Tool for rapid material and process screening.

Gessert, T.

2008-04-01T23:59:59.000Z

229

Investigation of Cd1-xMgxTe Alloys for Tandem Solar Cell Applications (Poster)  

DOE Green Energy (OSTI)

Fabrication and characterization of Cd{sub 1-x}Mg{sub x}Te(CMT) alloys and to determine their potential for device applications. Main emphasis is on the development of the devices in 1.5 to 1.8 eV range for the top cell of two-junction tandem solar cells. The conclusions are: (1) CMT alloy films with a wide composition range were fabricated; (2) the optical band gap shows a systematic variation with composition and CMT alloy films withstood the commonly used device processing steps for CdTe; and (3) they have fabricated cells with 5% efficiency in the energy gap range of 1.5 to 1.7 eV and established the viability of CMT for device applications.

Dhere, R.; Ramanathan, K.; Scharf, J.; Moutinho, H.; To, B.; Duda, A.; Noufi, R.

2006-05-01T23:59:59.000Z

230

Thermoelectric properties of AgGaTe$_2$ and related chalcopyrite structure materials  

Science Conference Proceedings (OSTI)

We present an analysis of the potential thermoelectric performance of p-type AgGaTe$_{2}$, which has already shown a $ZT$ of 0.8 with partial optimization, and observe that the same band structure features, such as a mixture of light and heavy bands and isotropic transport, that lead to this good performance are present in certain other ternary chalcopyrite structure semiconductors. We find that optimal performance of AgGaTe$_2$ will be found for hole concentrations between 4 $\\times 10^{19}$ and 2 $\\times 10^{20}$cm$^{-3}$ at 900 K, and 2 $\\times 10^{19}$ and 10$^{20}$ cm$^{-3}$ at 700 K, and that certain other chalcopyrite semiconductors might show good thermoelectric performance at similar doping ranges and temperatures if not for higher lattice thermal conductivity.

Parker, David S [ORNL; Singh, David J [ORNL

2012-01-01T23:59:59.000Z

231

Photoluminescence studies of type-II CdSe/CdTe superlattices  

SciTech Connect

CdSe/CdTe type-II superlattices grown on GaSb substrates by molecular beam epitaxy are studied using time-resolved and steady-state photoluminescence (PL) spectroscopy at 10 K. The relatively long carrier lifetime of 188 ns observed in time-resolved PL measurements shows good material quality. The steady-state PL peak position exhibits a blue shift with increasing excess carrier concentration. Self-consistent solutions of the Schroedinger and Poisson equations show that this effect can be explained by band bending as a result of the spatial separation of electrons and holes, which is critical confirmation of a strong type-II band edge alignment between CdSe and CdTe.

Li Jingjing; Johnson, Shane R.; Wang Shumin; Ding Ding; Ning Cunzheng; Zhang Yonghang [Center for Photonics Innovation, Arizona State University, Tempe, Arizona 85287-5706 (United States); School of Electrical, Computer, and Energy Engineering, Arizona State University, Tempe, Arizona 85287-5706 (United States); Yin Leijun [Center for Photonics Innovation, Arizona State University, Tempe, Arizona 85287-5706 (United States); Department of Physics, Arizona State University, Tempe, Arizona 85287-1504 (United States); Skromme, B. J. [School of Electrical, Computer, and Energy Engineering, Arizona State University, Tempe, Arizona 85287-5706 (United States); Liu Xinyu; Furdyna, Jacek K. [Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States)

2012-08-06T23:59:59.000Z

232

Search for microscopic black holes in pp collisions at sqrt(s) = 8 TeV  

E-Print Network (OSTI)

A search for microscopic black holes and string balls is presented, based on a data sample of pp collisions at sqrt(s) = 8 TeV recorded by the CMS experiment at the Large Hadron Collider and corresponding to an integrated luminosity of 12 inverse femtobarns. No excess of events with energetic multiparticle final states, typical of black hole production or of similar new physics processes, is observed. Given the agreement of the observations with the expected standard model background, which is dominated by QCD multijet production, 95% confidence limits are set on the production of semiclassical or quantum black holes, or of string balls, corresponding to the exclusions of masses below 4.3 to 6.2 TeV, depending on model assumptions. In addition, model-independent limits are set on new physics processes resulting in energetic multiparticle final states.

CMS Collaboration

2013-03-21T23:59:59.000Z

233

CdS/CdTe Thin-Film Solar Cell with a Zinc Stannate Buffer Layer  

DOE Green Energy (OSTI)

This paper describes an improved CdS/CdTe polycrystalline thin-film solar-cell device structure that integrates a zinc stannate (Zn2SnO4 or ZTO) buffer layer between the transparent conductive oxide (TCO) layer and the CdS window layer. Zinc stannate films have a high bandgap, high transmittance, low absorptance, and low surface roughness. In addition, these films are chemically stable and exhibit higher resistivities that are roughly matched to that of the CdS window layer in the device structure. Preliminary device results have demonstrated that by integrating a ZTO buffer layer in both SnO2-based and Cd2SnO4 (CTO)-based CdS/CdTe devices, performance and reproducibility can be significantly enhanced

Wu, X.; Sheldon, P.; Mahathongdy, Y.; Ribelin, R.; Mason, A.; Moutinho, H. R.; Coutts, T. J.

1998-10-28T23:59:59.000Z

234

Effect of Extended Defects in Planar and Pixelated CdZnTe Detectors  

Science Conference Proceedings (OSTI)

We evaluated a spectroscopy-grade 15 x 15 x 7 mm{sup 3} CdZnTe (CZT) crystal with a high {mu}{tau}-product, > 10{sup -2} cm{sup 2}/V, but impaired by microscopic extended defects, such as walls of dislocations, low-angle and sub-grain boundaries, and Te inclusions. First, we evaluated a planar detector fabricated from this crystal using a Microscale X-ray Detector Mapping (MXDM) technique. Then, we fabricated from the same crystal a pixel detector to study local non-uniformities of the electric field. The measured X-ray response maps confirmed the presence of non-uniformities in the charge transport, and they showed that the global- and local-distortions of the internal E-field correlated to the extended defects and space-charge buildup on the side surfaces.

C Camarda; K Andreini; A Bolotnikov; Y Cui; A Hossain; R Gul; K Kim; L Marchini; L Xu; et al.

2011-12-31T23:59:59.000Z

235

The High-Resolution Lightweight Telescope for the EUV (HiLiTE)  

SciTech Connect

The High-resolution Lightweight Telescope for the EUV (HiLiTE) is a Cassegrain telescope that will be made entirely of Silicon Carbide (SiC), optical substrates and metering structure alike. Using multilayer coatings, this instrument will be tuned to operate at the 465 {angstrom} Ne VII emission line, formed in solar transition region plasma at {approx}500,000 K. HiLiTE will have an aperture of 30 cm, angular resolution of {approx}0.2 arc seconds and operate at a cadence of {approx}5 seconds or less, having a mass that is about 1/4 that of one of the 20 cm aperture telescopes on the Atmospheric Imaging Assembly (AIA) instrument aboard NASA's Solar Dynamics Observatory (SDO). This new instrument technology thus serves as a path finder to a post-AIA, Explorer-class missions.

Martinez-Galarce, D S; Boerner, P; Soufli, R; De Pontieu, B; Katz, N; Title, A; Gullikson, E M; Robinson, J C; Baker, S L

2008-06-02T23:59:59.000Z

236

Crystallization Times of Ge-Te Phase Change Materials as a Function of Composition  

Science Conference Proceedings (OSTI)

The crystallization times of Ge-Te phase change materials with variable Ge concentrations (29.5-72.4 at. %) were studied. A very strong dependence of the crystallization time on the composition for as-deposited, amorphous films was confirmed, with a minimum for the stoichiometric composition GeTe. The dependence is weaker for melt-quenched, amorphous material and crystallization times are between one to almost four orders of magnitude shorter than for as-deposited materials. This is promising for applications because recrystallization from the melt-quenched phase is the relevant process for optical and solid state memory, and fast crystallization and weak dependence on compositional variations are desirable.

S Raoux; H Cheng; M Caldwell; H Wong

2011-12-31T23:59:59.000Z

237

Development of high-efficiency, thin-film CdTe solar cells. Final subcontract report, 1 February 1992--30 November 1995  

DOE Green Energy (OSTI)

This report describes work performed by the Georgia Institute of Technology (GIT) to bring the polycrystalline CdTe cell efficiency a step closer to the practically achievable efficiency of 18% through fundamental understanding of detects and loss mechanisms, the role of chemical and heat treatments, and investigation of now process techniques. The objective was addressed by a combination of in-depth characterization, modeling, materials growth, device fabrication, and `transport analyses of Au/Cu/CdTe/CdS/SnO {sub 2} glass front-wall heterojunction solar cells. GiT attempted to understand the loss mechanism(s) in each layer and interface by a step-by-step investigation of this multilayer cell structure. The first step was to understand, quantify, and reduce the reflectance and photocurrent loss in polycrystalline CdTe solar calls. The second step involved the investigation of detects and loss mechanisms associated with the CdTe layer and the CdTe/CdS interface. The third stop was to investigate the effect of chemical and heat treatments on CdTe films and cells. The fourth step was to achieve a better and reliable contact to CdTe solar cells by improving the fundamental understanding. Of the effects of Cu on cell efficiency. Finally, the research involved the investigation of the effect of crystallinity and grain boundaries on Cu incorporation in the CdTe films, including the fabrication of CdTe solar calls with larger CdTe grain size.

Rohatgi, A.; Chou, H.C.; Kamra, S.; Bhat, A. [Georgia Inst. of Tech., Atlanta, GA (United States)

1996-01-01T23:59:59.000Z

238

Electron scattering by acceptor centers in p-Ag{sub 2}Te at low temperatures  

Science Conference Proceedings (OSTI)

Resonant electron scattering in p-Ag{sub 2}Te at acceptor concentrations N{sub a} < 4.2 x 10{sup 16} cm{sup -3} has been observed in the temperature range of 50-80 K. The contribution of the resonant scattering to the temperature dependences of the conductivity {sigma}(T) and thermopower {alpha}{sub 0}(T) has been calculated. It is shown that this contribution exceeds that of charge carrier scattering by acoustic phonons.

Aliev, F. F., E-mail: farzali@physics.ab.az; Jafarov, M. B.; Askerova, G. Z. [Azerbaijan National Academy of Sciences, Institute of Physics (Azerbaijan); Gojaev, E. M. [Azerbaijan Technical University (Azerbaijan)

2010-08-15T23:59:59.000Z

239

Fabrication of stable, large-area, thin-film CdTe photovoltaic modules  

DOE Green Energy (OSTI)

Solar Cells, Inc (SCI) has a program to produce 60 cm X 120 cm solar modules based on CdTe films. The method of choice for semiconductor deposition is condensation from high temperature vapor's. Early work focussed on Close Spaced Sublimation and Chemical Vapor Deposition using elemental sources, but later equipment designs no longer strictly conform to either category. Small area efficiency has been confirmed by NREL at 9.3% on a 0.22 cm{sup 2} device (825 mV Voc, 18.2 mA/cm{sup 2} Jsc, and 0.62 FF) deposited on a 100 cm{sup 2} substrate. On 8 cell, 64 cm{sup 2} submodules, the best result to date is 7.3% (5.9 V Voc, 130 mA Isc, and 0.61 FF). CdS, CdTe, and ZnTe films have been deposited onto 60 cm X 120 cm substrates - single cells produced from this material have exceeded 8% efficiency, 64 cm{sup 2} submodules have exceeded 5%. Module efficiency is limited by mechanical defects - mostly shunts - associated with processing after deposition of the semiconductor layer's. Present best result is 1.4% total area efficiency. In anticipation of more advanced designs, CdTe films have also been deposited from apparatus employing elemental sources. This project is in an early stage and has produced only rudimentary results. A pro-active Safety, Health, Environmental and Disposal program has been developed. Results to date indicate that both employees and the environment have been protected against overexposure to hazards including toxic chemicals.

Nolan, J.F.; Meyers, P.V. (Solar Cells, Inc., Toledo, OH (United States))

1992-09-01T23:59:59.000Z

240

Thermographic analyses of the growth of Cd1-xZnxTe single crystals  

SciTech Connect

Bulk Cd1-xZnxTe (0

Kopach, O.V.; Bolotnikov, A.; Shcherbak, Larysa P.; Fochuk, Petro M.; and James, Ralph B.

2010-08-01T23:59:59.000Z

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241

Beam-induced backgrounds in the CLIC 3 TeV CM energy interaction region  

E-Print Network (OSTI)

Luminosity spectrum and accelerator background levels strongly influence the experimental conditions and have an important impact on detector design. The expected rates of the main beam-beam products at CLIC 3 TeV CM energy, taking into account for machine imperfections, are computed. Among the other machine-induced background the photon fans from the Incoherent Synchrotron Radiation (ISR) photons emitted in the final doublet are evaluated.

B. Dalena; J. Esberg; D. Schulte

2012-02-02T23:59:59.000Z

242

Photon + Jet production at sqrt{s}=1.96 TeV  

E-Print Network (OSTI)

Prompt photon production results by the CDF and D\\OCollaborations in the Tevatron Run II at a center of mass energy of $\\sqrt{s}$=1.96 TeV are presented. Cross sections for central isolated photons, photon+jet production and photons produced in association with a heavy flavor quark are reported. The measurements are compared to Next-to-Leading order perturbative QCD predictions.

C. Deluca

2009-05-13T23:59:59.000Z

243

Luminosity limitations at the multi-TeV linear collider energy frontier  

E-Print Network (OSTI)

To achieve the desired high luminosity in e+ e- linear colliders with centre-of-mass energies above the TeV scale, careful optimisation of the beam parameters is necessary. Constraints arising from the RF structure design, the beam-beam interaction, the damping ring and the beam delivery system have to be taken into account and compromises between different requirements have to be found. The nature of these different constraints is discussed and the resulting limits for the luminosity are detailed.

Schulte, Daniel

2002-01-01T23:59:59.000Z

244

TeV Observations of Markarian 501 with the Milagrito Water Cherenkov Detector  

E-Print Network (OSTI)

The Milagrito water Cherenkov detector near Los Alamos, New Mexico, operated as a sky monitor at energies of a few TeV between February 1997 and May 1998 including the period of the strong, long-lasting 1997 flare of Markarian 501. Milagrito served as a test run for the full Milagro detector. An event excess with a significance of 3.7 sigma from Markarian 501 was observed, in agreement with expectations.

R. Atkins

1999-09-04T23:59:59.000Z

245

Conductivity anisotropy in the doped Bi{sub 2}Te{sub 3} single crystals  

Science Conference Proceedings (OSTI)

Temperature dependences (temperature range T = 0.5-300 K) of resistivity in the plane of layers and in the direction perpendicular to the layers, and the galvanomagnetic effects in undoped and doped Bi{sub 2}Te{sub 3} single crystals are studied (magnetic field H < 80 kOe, T = 0.5-4.2 K). It is shown that upon doping of Bi{sub 2}Te{sub 3} with the Group III atoms (In and B), conductivity anisotropy increases mainly due to an increase in resistivity in the direction perpendicular to the layers. This fact makes it possible to assume that the atoms of these impurities are incorporated mainly into the van der Waal gaps between the layers upon doping. It is also revealed that, upon doping of Bi{sub 2}Te{sub 3} with In and B, the temperature dependence of conductivity becomes weaker, which indicates an increase in the role of scattering by defects in scattering mechanisms. The concentrations and mobilities of charge carriers, values of the Hall factor conditioned by the anisotropy of effective masses and orientation of ellipsoids with respect to crystallographic axes, areas of the extreme section of the Fermi surface by the plane perpendicular to the direction of the magnetic field, and the Fermi energy are evaluated.

Abdullaev, N. A., E-mail: anadir@azintex.com; Kakhramanov, S. Sh.; Kerimova, T. G.; Mustafayeva, K. M. [Azerbaijan National Academy of Sciences, Institute of Physics (Azerbaijan); Nemov, S. A. [St. Petersburg State Polytechnical University (Russian Federation)

2009-02-15T23:59:59.000Z

246

Study of Four Young TeV Pulsar Wind Nebulae with a Spectral Evolution Model  

E-Print Network (OSTI)

We study four young Pulsar Wind Nebulae (PWNe) detected in TeV gamma-rays, G21.5-0.9, G54.1+0.3, Kes 75, and G0.9+0.1, using the spectral evolution model developed and applied to the Crab Nebula in our previous work. We model the evolution of magnetic field and particle distribution function inside a uniformly expanding PWN considering a time-dependent injection from the pulsar and radiative and adiabatic losses. Considering uncertainties in the interstellar radiation field (ISRF) and their distance, we study two cases for each PWN. Because TeV PWNe have a large TeV gamma-rays to X-rays flux ratio, the magnetic energy of the PWNe accounts for only a small fraction of the total energy injected (typically a few x 10^{-3}). The gamma-ray emission is dominated by inverse Compton scattering off the infrared photons of the ISRF. A broken power-law distribution function for the injected particles reproduces the observed spectrum well, except for G0.9+0.1. For G0.9+0.1, we do not need a low energy counterpart because...

Tanaka, Shuta J

2011-01-01T23:59:59.000Z

247

Time dependent modelisation of TeV blazars by a stratified jet model  

E-Print Network (OSTI)

We present a new time-dependent inhomogeneous jet model of non-thermal blazar emission. Ultra-relativistic leptons are injected at the base of a jet and propagate along it. We assume continuous reacceleration and cooling, producing a relativistic quasi-maxwellian (or "pile-up") particle energy distribution. The synchrotron and Synchrotron-Self Compton jet emissivity are computed at each altitude. Klein-Nishina effects as well as intrinsic gamma-gamma absorption are included in the computation. Due to the pair production optical depth, considerable particle density enhancement can occur, particularly during flaring states.Time-dependent jet emission can be computed by varying the particle injection, but due to the sensitivity of pair production process, only small variations of the injected density are required during the flares. The stratification of the jet emission, together with a pile-up distribution, allows significantly lower bulk Lorentz factors, compared to one-zone models. Applying this model to the case of PKS 2155-304 and its big TeV flare observed in 2006, we can reproduce simultaneously the average broad band spectrum of this source from radio to TeV, as well as TeV light curve of the flare with bulk Lorentz factor lower than 15.

Timoth Boutelier; Gilles Henri; Pierre-Olivier Petrucci

2008-10-01T23:59:59.000Z

248

An inhomogeneous jet model for the rapid variability of TeV blazars  

E-Print Network (OSTI)

We present a new time-dependent inhomogeneous jet model of non-thermal blazar emission, which reproduces the entire spectral energy distribution together with the rapid gamma-ray variability. Ultra-relativistic leptons are injected at the base of a jet and propagate along the jet structure. We assume continuous reacceleration and cooling, producing a relativistic quasi-maxwellian (or "pile-up") particle energy distribution. The synchrotron and Synchrotron-Self Compton jet emissivity are computed at each altitude. Klein-Nishina effects as well as intrinsic gamma-gamma absorption are included in the computation. Due to the pair production optical depth, considerable particle density enhancement can occur, particularly during flaring states. Time-dependent jet emission can be computed by varying the particle injection, but due to the sensitivity of pair production process, only small variations of the injected density are required during the flares. The stratification of the jet emission, together with a pile-up distribution, allows significantly lower bulk Lorentz factors, compared to one-zone models. Applying this model to the case of PKS2155-304 and its big TeV flare observed in 2006, we can reproduce simultaneously the average broad band spectrum of this source as well as the TeV spectra and TeV light curve of the flare with bulk Lorentz factor lower than 15.

Timoth Boutelier; Gilles Henri; Pierre-Olivier Petrucci

2008-07-31T23:59:59.000Z

249

Investigation of Cd1-XMgxTe Alloys for Tandem Solar Cell Applications: Preprint  

DOE Green Energy (OSTI)

Theoretical modeling of two-junction tandem solar cells shows that for optimal device performance, the bandgap of the top cell should be in the range of 1.6 to 1.8 eV. Cd1-xMgxTe (CMT) alloys have a lattice constant close to that of CdTe, and the addition of a small amount of Mg changes the bandgap considerably. In this paper, we present our work on developing CMT for solar cell applications. CMT films were prepared by vacuum deposition with co-evaporation of CdTe and Mg on substrates heated to 300-400 C. Films with a composition in the range of x = 0 to 0.66 were fabricated, and optical analysis of the films showed that the bandgap of the samples ranged from 1.5 to 2.3 eV and varied linearly with composition. For the fabrication of devices using these alloy films, we also investigated the effect of post-deposition CdCl2 heat treatment. We have investigated junctions between CdS and CMT alloys in the bandgap range of 1.5 to 1.8 eV for tandem cell applications. We have also worked on the ohmic contacts to the CMT alloy films using Cu/Au bilayers, and the preliminary data shows a significant effect of the contact processing on the device performance.

Dhere, R.; Ramanathan, K.; Scharf, J.; Moutinho, H.; To, B.; Duda, A.; Noufi, R.

2006-05-01T23:59:59.000Z

250

Thin Film CIGS and CdTe Photovoltaic Technologies: Commercialization, Critical Issues, and Applications; Preprint  

DOE Green Energy (OSTI)

We report here on the major commercialization aspects of thin-film photovoltaic (PV) technologies based on CIGS and CdTe (a-Si and thin-Si are also reported for completeness on the status of thin-film PV). Worldwide silicon (Si) based PV technologies continues to dominate at more than 94% of the market share, with the share of thin-film PV at less than 6%. However, the market share for thin-film PV in the United States continues to grow rapidly over the past several years and in CY 2006, they had a substantial contribution of about 44%, compared to less than 10% in CY 2003. In CY 2007, thin-film PV market share is expected to surpass that of Si technology in the United States. Worldwide estimated projections for CY 2010 are that thin-film PV production capacity will be more than 3700 MW. A 40-MW thin-film CdTe solar field is currently being installed in Saxony, Germany, and will be completed in early CY 2009. The total project cost is Euro 130 million, which equates to an installed PV system price of Euro 3.25/-watt averaged over the entire solar project. This is the lowest price for any installed PV system in the world today. Critical research, development, and technology issues for thin-film CIGS and CdTe are also elucidated in this paper.

Ullal, H. S.; von Roedern, B.

2007-09-01T23:59:59.000Z

251

Overcoming Degradation Mechanisms in CdTe Solar Cells: Final Report, July 1998--September 2001  

DOE Green Energy (OSTI)

This report describes the stability of CdTe solar cells, with special focus on possible effects of diffusion from the contact to the absorber towards other cell components. Both whole cells and test systems containing only the ohmic contact and the absorber or only the window were used. We found that NiTe2 is a promising back-contact material. We also found that Cu as such is not the dominant factor in the most common and quickest type of degradation of these cells. An additional factor appears to be the formation of an oxide film on CdTe grains, which can be associated with the formation of the additional back-contact barrier that has been deduced from electrical characterization. Further observations were: Cell degradation appears to be promoted by H2O, O2, and illumination, in that order; less efficient cells are less stable than more efficient ones; some cells have been stabilized by heating in ultra-dry and O2-free inert atmosphere (N2 was used by us) before use, against subsequent degradation; and cells can recover by heating in dry N2 or by sitting on the shelf in ambient atmosphere.

Cahen, D.; Hodes, G.; Gartsman, K.

2002-03-01T23:59:59.000Z

252

Effect of Te Inclusions on the Performance of Cdznte Radiation Detectors  

Science Conference Proceedings (OSTI)

Te inclusions existing at high concentrations in CdZnTe (CZT) material can degrade the performance of CZT detectors. These microscopic defects trap the free electrons generated by incident radiation, so entailing significant fluctuations in the total collected charge and thereby strongly affecting the energy resolution of thick (long-drift) detectors. Such effects were demonstrated in thin planar detectors, and, in many cases, they proved to be the dominant cause of the low performance of thick detectors, wherein the fluctuations in the charge losses accumulate along the charge's drift path. We continued studying this effect using different tools and techniques. We employed a dedicated beamline recently established at BNL's National Synchrotron Light Source for characterizing semiconductor radiation detectors, along with an IR transmission microscope system, the combination of which allowed us to correlate the concentration of defects with the devices' performances. We present here our new results from testing over 50 CZT samples grown by different techniques. Our goals are to establish tolerable limits on the size and concentrations of these detrimental Te inclusions in CZT material, and to provide feedback to crystal growers to reduce their numbers in the material.

Bolotnikov, A.; Abdul-Jabbar, N; Babalola, O; Camarda, G; Cui, Y; Hossain, A; Jackson, E; Jackson, H; James, J; et. al.

2009-01-01T23:59:59.000Z

253

Development of high-efficiency, thin-film CdTe solar cells. Annual subcontract report, January 1, 1993--December 31, 1993  

DOE Green Energy (OSTI)

Polycrystalline thin film CdTe solar cells are one of the leading candidates for terrestrial photovoltaic applications. Theoretical calculations project an efficiency of 27% for single crystal, single junction CdTe cells, and the practically achievable efficiency for polycrystalline CdTe cells is 18-20%. Polycrystalline CdTe cells made by different groups show a significant variation in short circuit currents, open circuit voltages, and cell efficiencies. A better understanding of carrier loss and transport mechanism is crucial for explaining these differences, improving the yield, and bridging the gap between current and practically achievable limits in CdTe cell efficiencies. The goal of this program is to improve the understanding of the loss mechanisms in thin film CdS/CdTe solar cells and to improve their efficiency by characterizing the properties of the films as well as the finished devices.

Rohatgi, A.; Chou, H.C.; Kamra, S.; Bhat, A. [Georgia Institute of Technology, Atlanta, GA (United States)

1994-09-01T23:59:59.000Z

254

Development of CdS/CdTe Tin Film Devices for St. Gobain Coated Glass: Cooperative Research and Development Final Report, CRADA Number CRD-08-317  

DOE Green Energy (OSTI)

Research performed at NREL to produce CdS/CdTe devices on St. Gobain coated-glass material to establish a baseline CdS/CdTe device process and determine baseline device performance parameters on St. Gobain material. Performance of these baseline devices compared to similar devices produced by applying the established baseline CdS/CdTe process on alternative St. Gobain coated-glass materials.

Gessert, T.

2012-04-01T23:59:59.000Z

255

Room-temperature MBE deposition, thermoelectric properties, and advanced structural characterization of binary Bi[subscript 2]Te[subscript 3] and Sb[subscript 2]Te[subscript 3] thin films  

Science Conference Proceedings (OSTI)

Sb{sub 2}Te{sub 3} and Bi{sub 2}Te{sub 3} thin films were grown at room temperature on SiO{sub 2} and BaF{sub 2} substrates using molecular beam epitaxy. A layer-by-layer growth was achieved such that metallic layers of the elements with 0.2 nm thickness were deposited. The layer structure in the as-deposited films was confirmed by X-ray diffraction and was seen more clearly in Sb{sub 2}Te{sub 3} thin films. Subsequent annealing was done at 250 C for 2 h and produced the Sb{sub 2}Te{sub 3} and Bi{sub 2}Te{sub 3} crystal structure as confirmed by high-energy X-ray diffraction. This preparation process is referred to as nano-alloying and it was demonstrated to yield single-phase thin films of these compounds. In the thin films a significant texture could be identified with the crystal c axis being almost parallel to the growth direction for Sb{sub 2}Te{sub 3} and tilted by about 30{sup o} for Bi{sub 2}Te{sub 3} thin films. In-plane transport properties were measured for the annealed films at room temperature. Both films yielded a charge carrier density of about 2.6 x 10{sup 19} cm{sup -3}. The Sb{sub 2}Te{sub 3} films were p-type, had a thermopower of +130 {micro}V K{sup -1}, and surprisingly high mobilities of 402 cm{sup 2} V{sup -1} s{sup -1}. The Bi{sub 2}Te{sub 3} films were n-type, showed a thermopower of -153 {micro}V K{sup -1}, and yielded significantly smaller mobilities of 80 cm2 V{sup -1} s{sup -1}. The chemical composition and microstructure of the films were investigated by transmission electron microscopy (TEM) on cross sections of the thin films. The grain sizes were about 500 nm for the Sb{sub 2}Te{sub 3} and 250 nm for the Bi{sub 2}Te{sub 3} films. In the Bi{sub 2}Te{sub 3} thin film, energy-filtered TEM allowed to image a Bi-rich grain boundary phase, several nanometers thick. This secondary phase explains the poor mobilities of the Bi{sub 2}Te{sub 3} thin film. With these results the high potential of the nano-alloying deposition technique for growing films with a more complex layer architecture is demonstrated.

Peranio, N.; Winkler, M.; Bessas, D.; Aabdin, Z.; Knig, J.; Bttner, H.; Hermann, R.P.; Eibl, O. (Julich); (Tubingen); (Fraunhofer)

2012-10-23T23:59:59.000Z

256

Manufacturing Process Optimization to Improve Stability, Yield and Efficiency of CdS/CdTe PV Devices: Final Report, December 2004 - January 2009  

DOE Green Energy (OSTI)

The research by Colorado State University advances the understanding of device stability, efficiency, and process yield for CdTe PV devices.

Sampath, W. S.; Enzenroth, A.; Barth, K.

2009-03-01T23:59:59.000Z

257

The Crystallization Behavior of Stochiometric and Off-stochiometric Ga-Sb-Te Materials for Phase-Change Memory  

Science Conference Proceedings (OSTI)

The stoichiometric Ga{sub 4}Sb{sub 6}Te{sub 3} and Ga-Sb materials were systematically studied. The alloy Ga{sub 4}Sb{sub 6}Te{sub 3} shows a fast crystallization speed, very high crystallization temperature, T{sub x}, and high electrical contrast. Although stoichiometric GaSb has similar performance and even faster crystallization speed, the electrical contrast is much lower. The other off-stoichiometric compounds we studied all have higher T{sub x} than Ge{sub 2}Sb{sub 2}Te{sub 5} indicating a good amorphous stability. By raising the Sb/Te ratio with GaSb incorporation, T{sub x} and the recrystallization time of melt-quenched, amorphous samples can be effectively increased. The stoichiometric Ga{sub 4}Sb{sub 6}Te{sub 3} with less likelihood of phase-segregation compared to nonstoichiometric compounds is a promising candidate for phase-change memory.

H Cheng; S Raoux; J Jordan-Sweet

2011-12-31T23:59:59.000Z

258

Investigation of Junction Properties in CdS/CdTe Solar Cells and Their Correlation to Device Properties: Preprint  

DOE Green Energy (OSTI)

Secondary-ion mass spectrometry analysis of the CdS/CdTe interface shows that S diffusion in CdTe increases with substrate temperature and CdCl2 heat treatment. There is also an accumulation of Cl at the interface for CdCl2-treated samples. Modulated photo-reflectance studies shows that devices with CdCl2 heat treatment and open-circuit voltage (Voc) of 835 mV have a distinct high electric-field region in the layer with bandgap of 1.45 eV. Electron-beam induced current measurements reveal a one-sided junction for high Voc devices. The nature of the junction changes with processing. For heterojunction devices, the depletion region includes the highly defective CdS/CdTe interface, which would increase the recombination current and consequently the dark current, leading to lower Voc. In the case of CdCl2-treated cells, the n+-p junction and its high electric-field results in the junction between structurally compatible CdTe and the Te-rich CdSTe alloy, and thus, in higher Voc.

Dhere, R. G.; Zhang, Y.; Romero, M. J.; Asher, S. E.; Young, M.; To, B.; Noufi, R.; Gessert, T. A.

2008-05-01T23:59:59.000Z

259

The Fate of MAb targeted Cd125mTe/ZnS nanoparaticles in vivo  

Science Conference Proceedings (OSTI)

Nanoparticles (NP) have potential as carriers for drugs and radioisotopes. Quantitative measures of NP biodistribution in vivo are needed to determine the effectiveness of these carriers. We have used a model system of radiolabeled quantum dots to document the competition between efficient vascular targeting and interaction of the NP with the reticuloendothelial (RE) system. We have prepared (125m)Te-labeled CdTe NP that are capped with ZnS. Te-125m has a half-life and decay characteristics very similar to those for (125)I. The synthesized particles are stable in aqueous solution and are derivatized with mercaptoacetic acid and then conjugated with specific antibody. To evaluate specific targeting, we used the monoclonal antibody MAb 201B that binds to murine thrombomodulin expressed in the lumen of lung blood vessels. The MAb-targeted NP were tested for targeting performance in vivo using single-photon emission computed tomography (SPECT)/computed tomography (CT) imaging, tissue autoradiography and standard organ biodistribution techniques. Biodistribution was also determined in mice that had been depleted of phagocytic cells by use of clodronate-loaded liposomes. Cd(125m)Te/ZnS NP coupled with MAb 201B retained radioisotope and antibody activity and accumulated in lung (>400% injected dose [ID]/g) within 1 h of intravenous injection. Control antibody-coupled NP did not accumulate in lung (<10% ID/g) but accumulated in liver and spleen. Images from microSPECT/CT and autoradiography studies of the targeted NP document this specific uptake and demonstrate uniform distribution in lung with minor accumulation in liver and spleen. Within a few hours, a large fraction of lung-targeted NP redistributed to spleen and liver or was excreted. We hypothesized that NP attract phagocytic cells that engulfed and removed them from circulation. This was confirmed by comparing biodistribution of targeted NP in normal mice versus those depleted of phagocytic cells. In mice treated with clodronate liposomes, accumulation of NP in liver was reduced by fivefold, while accumulation in lung at 1 h was enhanced by approximately 50%. By 24 h, loss of the targeted NP from lung was inhibited by several-fold, while accumulation in liver and spleen remained constant. Thus, the treated mice had a much larger accumulation and retention of the NP at the target site and a decrease in dose to other organs except spleen. Nanoparticles composed of CdTe, labeled with (125m)Te and capped with ZnS, can be targeted with MAb to sites in the lumen of lung vasculature. In clodronate-treated mice, which have a temporary depletion of phagocytic cells, accumulation in liver was reduced dramatically, whereas that in spleen was not. The targeting to lung was several-fold more efficient in clodronate-treated mice due to larger initial accumulation and better retention of the MAb-targeted NP at that site. This model system indicates that targeting of NP preparations is a competition between the effectiveness of the targeting agent and the natural tendency for RE uptake of the particles. Temporary inhibition of the RE system may enhance the usefulness of NP for drug and radioisotope delivery.

Kennel, Steve J [ORNL; Woodward, Jonathan [ORNL; Rondinone, Adam Justin [ORNL; Wall, Jonathan [ORNL; Mirzadeh, Saed [ORNL

2008-01-01T23:59:59.000Z

260

Energy spectrum of charge carriers in Ag{sub 2}Te  

Science Conference Proceedings (OSTI)

Conductivity {sigma}(T) and Hall constant R(B, T) are studied for Ag{sub 2}Te with excess 0.1% of Te. The change in the R sign from (-) to (+) is found in dependences R(B) at various temperatures. In the temperature dependences of R in a range of 1-3 kG, two extrema are found, namely, minimum at T {approx} 60 and maximum at T {approx} 80 K, and at B {>=} 5 kG, the double change in sign of R from (-) to (+) and from (+) to (-) is found. Temperatures of sign inversion for R depend on the magnetic field. At B = 15 kG, the sign of R varies from (-) to (+) at T {approx} 38 K, and from (+) to (-) at T {approx} 70 K. It is found approximately in the region of the change in the sign of R(T), the concentration n(T) and electrical conductivity pass through the minimum. It is established that the minima of n(T) and {sigma}(T), extrema in R(T), and sign inversion for R(T) from (-) to (+) as well as the overestimated temperature dependence n{infinity}T{sup 4} are caused by localization of conduction electrons at acceptor levels entering the conduction band of Ag{sub 2}Te. The values of parameters of electrons (n, {mu}{sub n}) and holes (p, {mu}{sub p}) at the points of the change in the sign of R(T) from (-) to (+) and from (+) to (-) are determined.

Aliyev, S. A.; Agayev, Z. F., E-mail: agayevz@rambler.ru; Selimzadeh, R. I. [National Academy of Sciences of Azerbaijan, Institute of Physics (Azerbaijan)

2008-12-15T23:59:59.000Z

Note: This page contains sample records for the topic "graphi te hoback" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Quantum Anomalous Hall Effect in Hg_1-yMn_yTe Quantum Wells  

SciTech Connect

The quantum Hall effect is usually observed when the two-dimensional electron gas is subjected to an external magnetic field, so that their quantum states form Landau levels. In this work we predict that a new phenomenon, the quantum anomalous Hall effect, can be realized in Hg{sub 1-y}Mn{sub y}Te quantum wells, without the external magnetic field and the associated Landau levels. This effect arises purely from the spin polarization of the Mn atoms, and the quantized Hall conductance is predicted for a range of quantum well thickness and the concentration of the Mn atoms. This effect enables dissipationless charge current in spintronics devices.

Liu, Chao-Xing; /Tsinghua U., Beijing /Stanford U., Phys. Dept.; Qi, Xiao-Liang; /Stanford U., Phys. Dept.; Dai, Xi; Fang, Zhong; /Beijing, Inst. Phys.; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.

2010-03-19T23:59:59.000Z

262

Effect of annealing on the electrical properties of thallium-doped PbTe single crystals  

Science Conference Proceedings (OSTI)

It is found that electrical parameters of PbTe single crystals, the character of the dependences of these parameters on temperature and Tl impurity concentration, and the conductivity type (signs of {alpha} and R) are governed to a great extent by the temperature of preliminary annealing. The cause of this effect is that the concentration of doubly charged vacancies in the tellurium sublattice increases with an increase in the annealing temperature, as a result of which the formation of electrically neutral or singly charged complexes of impurity-vacancy type becomes more likely.

Ahmedova, G. A., E-mail: gulgunahmed@yahoo.com; Abdinova, G. J.; Abdinov, J. Sh. [National Academy of Sciences of Azerbaijan, Abdullaev Institute of Physics (Azerbaijan)

2011-02-15T23:59:59.000Z

263

TeV Scale Quantum Gravity and Mirror Supernovae as Sources of Gamma Ray Bursts  

E-Print Network (OSTI)

Mirror matter models have been suggested recently as an explanation of neutrino puzzles and microlensing anomalies. We show that mirror supernovae can be a copious source of energetic gamma rays if one assumes that the quantum gravity scale is in the TeV range. We show that under certain assumptions plausible in the mirror models, the gamma energies could be degraded to the 10 MeV range (and perhaps even further) so as to provide an explanation of observed gamma ray bursts. This mechanism for the origin of the gamma ray bursts has the advantage that it neatly avoids the ``baryon load problem''.

R. N. Mohapatra; S. Nussinov; V. L. Teplitz

1999-09-22T23:59:59.000Z

264

Technical evaluation of Solar Cells, Inc., CdTe modules and array at NREL  

DOE Green Energy (OSTI)

The Engineering and Technology Validation Team at the National Renewable Energy Laboratory (NREL) conducts in-situ technical evaluations of polycrystalline thin-film photovoltaic (PV) modules and arrays. This paper focuses on the technical evaluation of Solar Cells, Inc., (SCI) cadmium telluride (CdTe) module and array performance by attempting to correlate individual module and array performance. This is done by examining the performance and stability of the modules and array over a period of more than one year. Temperature coefficients for module and array parameters (P{sub max}V{sub oc}, V{sub max}, I{sub sc}, I{sub max}) are also calculated.

Kroposki, B.; Strand, T.; Hansen, R. [and others

1996-05-01T23:59:59.000Z

265

Plasmon-graviton conversion in a magnetic field in TeV-scale gravity  

E-Print Network (OSTI)

Kaluza-Klein (KK) gravitons emission rates due to plasmon-graviton conversion in magnetic field are computed within the ADD model of TeV-scale gravity. Plasma is described in the kinetic approach as the system of charged particles and Maxwell field both confined on the brane. Interaction with multidimensional gravity living in the bulk with $n$ compact extra dimensions is introduced within the linearized theory. Plasma collective effects enter through the two-point correlation function of the fluctuations of the energy-momentum tensor. The estimate for magnetic stars is presented leading to the lower limit of the D-dimensional Plank mass.

Melkumova, E Yu

2011-01-01T23:59:59.000Z

266

Scrutinizing the ZW+W- vertex at the Large Hadron Collider at 7 TeV  

E-Print Network (OSTI)

We analyze the potential of the CERN Large Hadron Collider running at 7 TeV to search for deviations from the Standard Model predictions for the triple gauge boson coupling ZW+W- assuming an integrated luminosity of 1 fb^{-1}. We show that the study of W+W- and W^\\pm Z productions, followed by the leptonic decay of the weak gauge bosons can improve the present sensitivity on the anomalous couplings \\Delta g_1^Z, \\Delta \\kappa_Z, \\lambda_Z, g_4^Z, and \\tilde{\\lambda}_Z at the 2\\sigma level.

O. J. P. Eboli; J. Gonzalez-Fraile; M. C. Gonzalez-Garcia

2010-06-17T23:59:59.000Z

267

Size-Dependent Polar Ordering on Colloidal GeTe Nanocrystals  

SciTech Connect

The question of the nature and stability of polar ordering in nanoscale ferroelectrics is examined with colloidal nanocrystals of germanium telluride (GeTe). We provide atomic-scale evidence for room-temperature polar ordering in individual nanocrystals using aberration-corrected transmission electron microscopy and demonstrate a reversible, size-dependent polar-nonpolar phase transition of displacive character in nanocrystal ensembles. A substantial linear component of the distortion is observed, which is in contrast with theoretical reports predicting a toroidal state.

M Polking; J Urban; D Milliron; H Zheng; E Chan; M Caldwell; S Raoux; C Kisielowski; J Ager; et al.

2011-12-31T23:59:59.000Z

268

Unconventional fermions: The Price of Quark-Lepton Unification at TeV Scales  

E-Print Network (OSTI)

The early petite unification (PUT) of quarks and leptons at TeV scales with sin^2 theta_W(M^2_Z) used as a constraint, necessitates the introduction of extra quarks and leptons with unconventional electric charges (up to 4/3 for the quarks and 2 for the leptons). This talk, in honor of Paul Frampton's 60th birthday, will be devoted to the motivation and construction of models of early unification and to their implications, including the issues of rare decays and unconventional fermions.

P. Q. Hung

2004-06-23T23:59:59.000Z

269

Effect of Sub-Bandgap Illumination on the Internal Electric Field of CdZnTe  

SciTech Connect

Post-growth manipulation of the internal electric field in CdZnTe crystals using sub-bandgap illumination is measured as a function of temperature through infrared (IR) transmission measurements. Using near sub-bandgap IR illumination, both the optical de-trapping of charge carriers and the reduction in carrier recombination increased the mobility lifetime in the crystal. The increased carrier transport is a direct result of decreased hole and electron trapping in addition to other underlying mechanisms. Concentration of the electric field near the cathode is also observed. We measured the electric field distribution with sub-bandgap illumination as a function of temperature via the Pockels effect.

Washington, A.

2011-09-16T23:59:59.000Z

270

Flexible Micro Thermoelectric Generator based on Electroplated Bi2Te3  

E-Print Network (OSTI)

We present and discuss the fabrication process and the performance of a flexible micro thermoelectric generator with electroplated Bi2Te3 thermocouples in a SU-8 mold. Demonstrator devices generate 278uWcm-2 at dTmeas=40K across the experimental set up. Based on model calculations, a temperature difference of dTG=21.4K across the generator is assumed. Due to the flexible design and the chosen generator materials, the performance stays high even for curved contact surfaces. The measurement results correlate well with the model based design optimization predictions.

Schwyter, E; Durrer, L; Hierold, Ch

2008-01-01T23:59:59.000Z

271

High-Efficiency CdTe and CIGS Thin-Film Solar Cells: Highlights and Challenges  

Science Conference Proceedings (OSTI)

Thin-film photovoltaic (PV) modules of CdTe and Cu(In,Ga)Se{sub 2} (CIGS) have the potential to reach cost-effective PV-generated electricity. These technologies have transitioned from the laboratory to the market place. Pilot production and first-time manufacturing are ramping up to higher capacity and enjoying a flood of venture-capital funding. CIGS solar cells and modules have achieved 19.5% and 13% efficiencies, respectively. Likewise, CdTe cells and modules have reached 16.5% and 10.2% efficiencies, respectively. Even higher efficiencies from the laboratory and from the manufacturing line are only a matter of time. Manufacturing-line yield continues to improve and is surpassing 85%. Long-term stability has been demonstrated for both technologies; however, some failures in the field have also been observed, emphasizing the critical need for understanding degradation mechanisms and packaging options. These two thin-film technologies have a common device/module structure: substrate, base electrode, absorber, junction layer, top electrode, patterning steps for monolithic integration, and encapsulation. The monolithic integration of thin-film solar cells can lead to significant manufacturing cost reduction compared to crystalline Si technology. The CdTe and CIGS modules share common structural elements. In principle, this commonality should lead to similar manufacturing cost per unit area, and thus, the module efficiency becomes the discriminating factor that determines the cost per watt. The long-term potential of the two technologies require R&D emphasis on science and engineering-based challenges to find solutions to achieve targeted cost-effective module performance, and in-field durability. Some of the challenges are common to both, e.g., in-situ process control and diagnostics, thinner absorber, understanding degradation mechanisms, protection from water vapor, and innovation in high-speed processing and module design. Other topics are specific to the technology, such as lower-cost and fast-deposition processes for CIGS, and improved back contact and voltage for CdTe devices.

Noufi, R.; Zweibel, K.

2006-01-01T23:59:59.000Z

272

Role of polycrystallinity in CdTe and CuInSe[sub 2] photovoltaic cells  

DOE Green Energy (OSTI)

The limiting role of polycrystallinity in thin-film solar calls has been reduced somewhat during the past year, and efficiencies of both CdTe and CuInSe[sub 2] cells are approaching 15%. Quantitative separation of loss mechanisms shows that individual losses, with the exception of forward recombination current, can be made comparable to their single crystal counterparts. One general manifestation of the extraneous trapping states in that the voltage of all polycrystalline thin-film cells drifts upward by 10--50 mV following the onset of illumination.

Sites, J.R. (Colorado State Univ., Fort Collins, CO (United States))

1992-11-01T23:59:59.000Z

273

Role of Copper in the Performance of CdS/CdTe Solar Cells: Preprint  

DOE Green Energy (OSTI)

The performance of CdS/CdTe solar cells made with evaporated Cu as a primary back contact was studied through current-voltage (JV) at different intensities, quantum efficiency (QE) under light and voltage bias, capacitance-voltage (CV), and drive-level capacitance profiling (DLCP) measurements. The results show that while modest amounts of Cu enhance cell performance, excessive amounts degrade device quality and reduce performance. The analysis is supported with numerical simulations to reproduce and explain some of the experimental results.

Demtsu, S.; Albin, D.; Sites, J.

2006-05-01T23:59:59.000Z

274

Role of Copper in the Performance of CdS/CdTe Solar Cells (Poster)  

DOE Green Energy (OSTI)

The performance of CdS/CdTe solar cells made with evaporated Cu as a primary back contact was studied through current-voltage (JV) at different intensities, quantum efficiency (QE) under light and voltage bias, capacitance-voltage (CV), and drive-level capacitance profiling (DLCP) measurements. The results show that while modest amounts of Cu enhance cell performance, excessive amounts degrade device quality and reduce performance. The analysis is supported with numerical simulations to reproduce and explain some of the experimental results.

Demtsu, S.; Albin, D.; Sites, J.

2006-05-01T23:59:59.000Z

275

Shell model calculation for Te and Sn isotopes in the vicinity of {sup 100}Sn  

SciTech Connect

New Shell Model calculations for even-even isotopes {sup 104-108}Sn and {sup 106,108}Te, in the vicinity of {sup 100}Sn have been performed. The calculations have been carried out using the windows version of NuShell-MSU. The two body matrix elements TBMEs of the effective interaction between valence nucleons are obtained from the renormalized two body effective interaction based on G-matrix derived from the CD-bonn nucleon-nucleon potential. The single particle energies of the proton and neutron valence spaces orbitals are defined from the available spectra of lightest odd isotopes of Sb and Sn respectively.

Yakhelef, A.; Bouldjedri, A. [Physics Department, Farhat abbas University, Setif (Algeria); Physics Department, Hadj Lakhdar University, Batna (Algeria)

2012-06-27T23:59:59.000Z

276

Synchrotron X-ray Based Characterization of CdZnTe Crystals  

Science Conference Proceedings (OSTI)

Synthetic CdZnTe (CZT) crystals can be used for the room temperature-based detection of gamma radiation. Structural/morphological heterogeneities within CZT, such as secondary phases (namely, precipitates and inclusions), can negatively affect detector performance. We used a synchrotron-based x-ray technique, specifically extended x-ray absorption fine-structure (EXAFS) spectroscopy, to determine whether there are differences on a local structural level between intact CZT of high and low radiation detector performance. These studies were complemented by data on radiation detector performance and transmission infrared (IR) imaging. The EXAFS studies revealed no detectable local structural differences between the two types of CZT materials.

Duff,M.; Hunter, D.; Nuessle, P.; Black, D.; Burdette, H.; Woicik, J.; Burger, A.; Groza, M.

2007-01-01T23:59:59.000Z

277

Hidden from View: Neutrino Masses, Dark Matter and TeV-Scale Leptogenesis in a Neutrinophilic 2HDM  

E-Print Network (OSTI)

We consider a simple extension of the Standard Model providing dark matter and a TeV-scale seesaw mechanism that also allows for viable leptogenesis. In addition to the Standard Model degrees of freedom, the model contains a neutrinophilic Higgs doublet, a scalar singlet, and six singlet fermions (including three right-handed Majorana neutrinos) that are charged under a local $U(1)^\\prime$ gauge symmetry. We show how the $U(1)^\\prime$ charge assignments and the choice of scalar potential can lead to a TeV-scale seesaw mechanism and $\\mathcal{O}(1)$ neutrino Yukawa couplings in a straightforward way. While this scenario has all the ingredients one would expect for significant experimental signatures, including several new TeV scale degrees of freedom, we find that most distinctive features associated with neutrino mass generation, leptogenesis and the dark sector are likely to remain inaccessible in the absence of additional lepton flavor symmetries.

Wei Chao; Michael J. Ramsey-Musolf

2012-12-22T23:59:59.000Z

278

Guideline to good practices for control and calibration of measuring and test equipment (M TE) at DOE nuclear facilities  

Science Conference Proceedings (OSTI)

The purpose of the Guideline to Good Practices for Control and Calibration of Measuring and Test Equipment (M TE) at DOE Nuclear Facilities is to provide contractor maintenance organizations with information that may be used for the development and implementation of a rigorously controlled maintenance program directed at controlling and calibrating M TE used for maintenance tasks at DOE nuclear facilities. This document is intended to be an example guideline for the implementation of DOE Order 4330.4A, Maintenance Management Program, Chapter II, Element 11. DOE contractors should not feel obligated to adopt all parts of this guide. Rather, they should use the information contained herein as a guide for developing an M TE program applicable to their facility.

Not Available

1993-03-01T23:59:59.000Z

279

Reduction of surface leakage current by surface passivation of CdZn Te and other materials using hyperthermal oxygen atoms  

DOE Patents (OSTI)

Reduction of surface leakage current by surface passivation of Cd.sub.1-x Zn.sub.x Te and other materials using hyperthermal oxygen atoms. Surface effects are important in the performance of CdZnTe room-temperature radiation detectors used as spectrometers since the dark current is often dominated by surface leakage. A process using high-kinetic-energy, neutral oxygen atoms (.about.3 eV) to treat the surface of CdZnTe detectors at or near ambient temperatures is described. Improvements in detector performance include significantly reduced leakage current which results in lower detector noise and greater energy resolution for radiation measurements of gamma- and X-rays, thereby increasing the accuracy and sensitivity of measurements of radionuclides having complex gamma-ray spectra, including special nuclear materials.

Hoffbauer, Mark A. (Los Alamos, NM); Prettyman, Thomas H. (Los Alamos, NM)

2001-01-01T23:59:59.000Z

280

{gamma}-ray spectroscopy of neutron-deficient {sup 110}Te. I. Low- and intermediate-spin structures  

SciTech Connect

Excited states have been populated in {sub 52}{sup 110}Te via the {sup 58}Ni({sup 58}Ni,{alpha}2p{gamma}) reaction at 250 MeV. The Gammasphere {gamma}-ray spectrometer was augmented with ancillary detectors for charged-particle and neutron detection in order to provide clean channel selection. The known level scheme of {sup 110}Te has been greatly expanded with the addition of many new structures. Above spin 8{sup +}, negative-parity structures become yrast. The level scheme of {sup 110}Te below 30({Dirac_h}/2{pi}) is discussed in this paper, including possible evidence for octupole correlations inferred from strong B(E1) strengths.

Paul, E. S.; Boston, A. J.; Nolan, P. J.; Semple, A. T. [Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 7ZE (United Kingdom); Chiara, C. J.; Fossan, D. B.; Lane, G. J.; Sears, J. M.; Starosta, K. [Department of Physics and Astronomy, State University of New York at Stony Brook, Stony Brook, New York 11794-3800 (United States); Devlin, M.; LaFosse, D. R.; Sarantites, D. G. [Department of Chemistry, Washington University, St. Louis, Missouri 63130 (United States); Freeman, S. J.; Leddy, M. J. [Schuster Laboratory, University of Manchester, Brunswick Street, Manchester M13 9PL (United Kingdom); Lee, I. Y.; Macchiavelli, A. O. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Smith, J. F. [Department of Physics and Astronomy, State University of New York at Stony Brook, Stony Brook, New York 11794-3800 (United States); Schuster Laboratory, University of Manchester, Brunswick Street, Manchester M13 9PL (United Kingdom)

2007-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "graphi te hoback" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

RECYCLING OF CdTe PHOTOVOLTAIC MODULES: RECOVERY OF CADMIUM AND TELLURIUM Vasilis Fthenakis1, Paul Duby2, Wenming Wang1, Christopher Graves2 & Anuta Belova2  

E-Print Network (OSTI)

RECYCLING OF CdTe PHOTOVOLTAIC MODULES: RECOVERY OF CADMIUM AND TELLURIUM Vasilis Fthenakis1, Paul the recovery of tellurium. Keywords: Photovoltaic, Recycling, CdTe 1. INTRODUCTION Photovoltaic modules on a larger scale cell (i.e., 5 L) which prod

282

CANGAROO-III OBSERVATION OF TeV GAMMA RAYS FROM THE VICINITY OF PSR B1706-44  

Science Conference Proceedings (OSTI)

Observation by the CANGAROO-III stereoscopic system of the Imaging Cherenkov Telescope has detected extended emission of TeV gamma rays in the vicinity of the pulsar PSR B1706-44. The strength of the signal observed as gamma-ray-like events varies when we apply different ways of emulating background events. The reason for such uncertainties is argued in relevance to gamma rays embedded in the 'OFF-source data', that is, unknown sources and diffuse emission in the Galactic plane, namely, the existence of a complex structure of TeV gamma-ray emission around PSR B1706-44.

Enomoto, R.; Kifune, T. [Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Kushida, J.; Hattori, T.; Ishioka, H.; Kawachi, A. [Department of Physics, Tokai University, Hiratsuka, Kanagawa 259-1292 (Japan); Nakamori, T. [Department of Basic Physics, Tokyo Institute of Technology, Meguro, Tokyo, 152-8551 (Japan); Bicknell, G. V. [Research School of Astronomy and Astrophysics, Australian National University, ACT 2611 (Australia); Clay, R. W. [School of Chemistry and Physics, University of Adelaide, SA 5005 (Australia); Edwards, P. G. [Narrabri Observatory of the Australia Telescope National Facility, CSIRO, Epping, NSW 2121 (Australia); Gunji, S.; Inoue, K. [Department of Physics, Yamagata University, Yamagata 990-8560 (Japan); Hara, S. [Ibaraki Prefectural University of Health Sciences, Ami, Ibaraki 300-0394 (Japan); Hara, T. [Faculty of Management Information, Yamanashi Gakuin University, Kofu, Yamanashi 400-8575 (Japan); Hayashi, S.; Kajino, F. [Department of Physics, Konan University, Kobe, Hyogo 658-8501 (Japan); Higashi, Y.; Kabuki, S. [Department of Physics, Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan); Hirai, Y. [Faculty of Science, Ibaraki University, Mito, Ibaraki 310-8512 (Japan); Katagiri, H. [Department of Physical Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan)

2009-10-01T23:59:59.000Z

283

Structural, thermal, optical, and photoacoustic study of nanocrystalline Bi{sub 2}Te{sub 3} produced by mechanical alloying  

SciTech Connect

Nanocrystalline Bi{sub 2}Te{sub 3} was produced by mechanical alloying and its properties were investigated by differential scanning calorimetry (DSC) x-ray diffraction (XRD), Raman spectroscopy (RS), and photoacoustic spectroscopy (PAS). Combining the XRD and RS results, the volume fraction of the interfacial component in as-milled and annealed samples was estimated. The PAS results suggest that the contribution of the interfacial component to the thermal diffusivity of nanostructured Bi{sub 2}Te{sub 3} is very significant.

Souza, S. M.; Triches, D. M.; Poffo, C. M. [Departamento de Engenharia Mecanica, Universidade Federal de Santa Catarina, Campus Universitario Trindade, C.P. 476, Florianopolis, Santa Catarina 88040-900 (Brazil); Lima, J. C. de; Grandi, T. A. [Departamento de Fisica, Universidade Federal de Santa Catarina, Campus Trindade, C.P. 476, Florianopolis, Santa Catarina 88040-900 (Brazil); Biasi, R. S. de [Secao de Engenharia Mecanica e de Materiais, Instituto Militar de Engenharia, 22290-270 Rio de Janeiro-RJ (Brazil)

2011-01-01T23:59:59.000Z

284

WE?G?500?08: Novel Multilayer Detector Design Using Polycrystalline CdTe for Radiation Therapy Imaging Applications  

Science Conference Proceedings (OSTI)

Purpose: In radiation therapy treatments the standard approach of taking a planar portal or CIAO image offers setup verifications crucial to accurate radiation delivery. A substantial detector thickness necessary for MV photon absorption is a limitation due to large signal spreading; the requirements of large areas (up to 4040 cm) and commercial viability dictate the use of non?crystalline semiconductors. We propose a detector based on thin?film CdTe technologies recently developed for photovoltaic applications. It utilizes a stack of CdTe photovoltaic layers

2013-01-01T23:59:59.000Z

285

Crystal Defects in CdZnTe Crystals Grown by the Modified Low-Pressure Bridgman Method  

Science Conference Proceedings (OSTI)

Cadmium Zinc Telluride (CZT) is among the most promising materials for room-temperature X- and gamma-ray detectors. However, crystal defects such as Te inclusions and subgrain boundaries significantly hamper their performances. In this work, we evaluated CZT crystals grown by the modified low-pressure Bridgman technique at the IMEM Institute, Parma. We characterized the crystals by IR microscopy to identify the sizes and concentrations of the Te inclusions, along with high spatial resolution X-ray response mapping to measure the uniformity of their charge-transport properties. In addition, we employed white X-ray beam diffraction topography to analyze their crystalline structure.

Bolotnikov A.; Marchini, L.; Zappettini, M.; Zha, M.; Zambelli, N.; Camarda, G.S.; James, R.B.

2012-04-13T23:59:59.000Z

286

High-spin structures of 124-131Te: Competition of proton and neutron pair breakings  

E-Print Network (OSTI)

The 124-131Te nuclei have been produced as fission fragments in two fusion reactions induced by heavy-ions (12C + 238U at 90 MeV bombarding energy and 18O + 208Pb at 85 MeV) and studied with the Euroball array. Their high-spin level schemes have been extended to higher excitation energy from the triple gamma-ray coincidence data. The gamma-gamma angular correlations have been analyzed in order to assign spin and parity values to many observed states. Moreover the half-lives of isomeric states have been measured from the delayed coincidences between the fission-fragment detector SAPhIR and Euroball, as well as from the timing information of the Ge detectors. The behaviors of the yrast structures identified in the present work are first discussed in comparison with the general features known in the mass region, particularly the breakings of neutron pairs occupying the nuh11/2 orbit identified in the neighboring Sn nuclei. The experimental level schemes are then compared to shell-model calculations performed in this work. The analysis of the wave functions shows the effects of the proton-pair breaking along the yrast lines of the heavy Te isotopes.

A. Astier; M. -G. Porquet; Ts. Venkova; Ch. Theisen; G. Duchene; F. Azaiez; G. Barreau; D. Curien; I. Deloncle; O. Dorvaux; B. J. P. Gall; M. Houry; R. Lucas; N. Redon; M. Rousseau; O. Stezowski

2013-12-17T23:59:59.000Z

287

Innovative sputtering techniques for CIS and CdTe submodule fabrication  

DOE Green Energy (OSTI)

This report describes work done during Phase 1 of the subject subcontract. The subcontract was designed to study innovative deposition techniques, such as the rotating cylindrical magnetron sputtering system and electrodeposition for large-area, low-cost copper indium diselenide (CIS) and cadmium telluride (CdTe) devices. A key issue for photovoltaics (PV) in terrestrial and future space applications is producibility, particularly for applications using a large quantity of PV. Among the concerns for fabrication of polycrystalline thin-film PV, such as CIS and CdTe, are production volume, cost, and minimization of waste. Both rotating cylindrical magnetron (C-Mag[trademark]) sputtering and electrodeposition have tremendous potential for the fabrication of polycrystalline thin-film PV due to scaleability, efficient utilization of source materials, and inherently higher deposition rates. In the case of sputtering, the unique geometry of the C-Mae facilitates innovative cosputtering and reactive sputtering that could lead to greater throughput reduced health and safety risks, and, ultimately, lower fabrication cost. Electrodeposited films appear to be adherent and comparable with low-cost fabrication techniques. Phase I involved the initial film and device fabrication using the two techniques mentioned herein. Devices were tested by both internal facilities, as well as NREL and ISET.

Armstrong, J.M.; Misra, M.S.; Lanning, B. (Martin Marietta Aerospace, Denver, CO (United States). Astronautics Group)

1993-03-01T23:59:59.000Z

288

Improved Intrinsic Stability of CdTe Polycrystalline Thin Film Devices  

DOE Green Energy (OSTI)

A systems-driven approach linking upstream solar cell device fabrication history with downstream performance and stability has been applied to CdS/CdTe small-area device research. The best resulting initial performance (using thinner CdS, thicker CdTe, no oxygen during VCC, and the use of NP etch) was shown to simultaneously correlate with poor stability. Increasing the CdS layer thickness significantly improved stability at only a slight decrease in overall performance. It was also determined that cell perimeter effects can accelerate degradation in these devices. A ''margined'' contact significantly reduces the contribution of edge shunting to degradation, and thus yields a more accurate determination of the intrinsic stability. Pspice discrete element models demonstrate how spatially localized defects can effectively dominate degradation. Mitigation of extrinsic shunting improved stabilized efficiency degradation levels (SEDL) to near 20% in 100 C tests. Further process optimization to reduce intrinsic effects improved SEDL to better than 10% at the same stress temperatures and times.

Albin, D.; Berniard, T.; McMahon, T.; Noufi, R.; Demtsu, S.

2005-01-01T23:59:59.000Z

289

Cosmic ray knee and new physics at the TeV scale  

E-Print Network (OSTI)

We analyze the possibility that the cosmic ray knee appears at an energy threshold where the proton-dark matter cross section becomes large due to new TeV physics. It has been shown that such interactions could break the proton and produce a diffuse gamma ray flux consistent with MILAGRO observations. We argue that this hypothesis implies knees that scale with the atomic mass for the different nuclei, as KASKADE data seem to indicate. We find that to explain the change in the spectral index in the flux from E^{-2.7} to E^{-3.1} the cross section must grow like E^{0.4+\\beta} above the knee, where \\beta=0.3-0.6 parametrizes the energy dependence of the age (\\tau \\propto E^{-\\beta}) of the cosmic rays reaching the Earth. The hypothesis also requires mbarn cross sections (that could be modelled with TeV gravity) and large densities of dark matter (that could be clumped around the sources of cosmic rays). We argue that neutrinos would also exhibit a threshold at E=(m_\\chi/m_p)E_{knee}\\approx 10^8 GeV where their interaction with a nucleon becomes strong. Therefore, the observation at ICECUBE or ANITA of standard neutrino events above this threshold would disprove the scenario.

Roberto Barcelo; Manuel Masip; Iacopo Mastromatteo

2009-03-30T23:59:59.000Z

290

Cosmic ray knee and new physics at the TeV scale  

E-Print Network (OSTI)

We analyze the possibility that the cosmic ray knee appears at an energy threshold where the proton-dark matter cross section becomes large due to new TeV physics. It has been shown that such interactions could break the proton and produce a diffuse gamma ray flux consistent with MILAGRO observations. We argue that this hypothesis implies knees that scale with the atomic mass for the different nuclei, as KASKADE data seem to indicate. We find that to explain the change in the spectral index in the flux from E^{-2.7} to E^{-3.1} the cross section must grow like E^{0.4+\\beta} above the knee, where \\beta=0.3-0.6 parametrizes the energy dependence of the age (\\tau \\propto E^{-\\beta}) of the cosmic rays reaching the Earth. The hypothesis also requires mbarn cross sections (that could be modelled with TeV gravity) and large dark matter densities in the galactic disc (that might be accommodated in a two-component model). We argue that neutrinos would also exhibit a threshold at E=(m_\\chi/m_p)E_{knee}\\approx 10^8 GeV...

Barcelo, Roberto; Mastromatteo, Iacopo

2009-01-01T23:59:59.000Z

291

Measurements of the Cerenkov light emitted by a TeO2 crystal  

E-Print Network (OSTI)

Bolometers have proven to be good instruments to search for rare processes because of their excellent energy resolution and their extremely low intrinsic background. In this kind of detectors, the capability of discriminating alpha particles from electrons represents an important aspect for the background reduction. One possibility for obtaining such a discrimination is provided by the detection of the Cerenkov light which, at the low energies of the natural radioactivity, is only emitted by electrons. In this paper, the results of the analysis of the light emitted by a TeO2 crystal at room temperature when transversed by a cosmic ray are reported. Light is promptly emitted after the particle crossing and a clear evidence of its directionality is also found. These results represent a strong indication that Cerenkov light is the main, if not even the only, component of the light signal in a TeO2 crystal. They open the possibility to make large improvements in the performance of experiments based on this kind of materials

F. Bellini; N. Casali; I. Dafinei; M. Marafini; S. Morganti; F. Orio; D. Pinci; M. Vignati; C. Voena

2012-09-27T23:59:59.000Z

292

SHI induced enhancement in conductivity of PbTe thin film for thermoelectric applications  

SciTech Connect

PbTe thin film were synthesized using thermal evaporation and irradiated by 100 MeV Ag ions at different fluences ranging from 3x10{sup 13} and 1x10{sup 14} ions/cm{sup 2}. Pristine films annealed under Ar atm at 250 deg. C for 1 hr. X-ray Diffraction (XRD) of pristine and irradiated films reveals the improvement of PbTe phase with increasing fluence. The thickness of the film is decreased from 195 nm to 150 nm after ion irradiation as indicated by Rutherford backscattering spectrometry (RBS) analysis due to the sputtering. Resistivity measurement using four probe techniques of these films shows the conductivity enhancement with ion fluence. The conductivity is found to be {approx} 6 fold at fluence 3x10{sup 13} ions/cm{sup 2} whereas it decreases to 3 fold after annealing in comparison to pristine sample. On further increasing the fluence from 3x10{sup 13} ions/cm{sup 2}, the properties of the film begin to deteriorate. SHI induced modification may be explained on the basis of oxygen desorption and change in stochiometry of film during irradiation.

Gupta, Srashti; Agarwal, D. C.; Singh, J. P.; Tripathi, S. K.; Neeleshwar, S.; Asokan, K.; Panigrahi, B. K.; Avasthi, D. K. [University School of Basic and Applied Sciences, GGS Indraprastha University, Dwarka, Delhi 110075 (India); Inter University Accelerator Centre, New Delhi-110067 (India); Department of Physics, Panjab University, Chandigarh-160 014 (India); University School of Basic and Applied Sciences, GGS Indraprastha University, Dwarka, Delhi 110075 (India); Inter University Accelerator Centre, New Delhi-110067 (India); Materials Science Division, Indira Gandhi Centre for Atomic Research, Kalpakkam-603102 (India); Inter University Accelerator Centre, New Delhi-110067 (India)

2012-06-05T23:59:59.000Z

293

TeV Burst of Gamma-Ray Bursts and Ultra High Energy Cosmic Rays  

E-Print Network (OSTI)

Some recent experiments detecting very high energy (VHE) gamma-rays above 10-20 TeV independently reported VHE bursts for some of bright gamma-ray bursts (GRBs). If these signals are truly from GRBs, these GRBs must emit a much larger amount of energy as VHE gamma-rays than in the ordinary photon energy range of GRBs (keV-MeV). We show that such extreme phenomena can be reasonably explained by synchrotron radiation of protons accelerated to \\sim 10^{20-21} eV, which has been predicted by Totani (1998a). Protons seem to carry about (m_p/m_e) times larger energy than electrons, and hence the total energy liberated by one GRB becomes as large as \\sim 10^{56} (\\Delta \\Omega / 4 \\pi) ergs. Therefore a strong beaming of GRB emission is highly likely. Extension of the VHE spectrum beyond 20 TeV gives a nearly model-independent lower limit of the Lorentz factor of GRBs, as $\\gamma \\gtilde 500$. Furthermore, our model gives the correct energy range and time variability of ordinary keV-MeV gamma-rays of GRBs by synchrotron radiation of electrons. Therefore the VHE bursts of GRBs strongly support the hypothesis that ultra high energy cosmic rays observed on the Earth are produced by GRBs.

Tomonori Totani

1998-10-14T23:59:59.000Z

294

Charge transport properties in CdZnTe detectors grown by the vertical Bridgman technique  

Science Conference Proceedings (OSTI)

Presently, a great amount of effort is being devoted to the development of CdTe and CdZnTe (CZT) detectors for a large variety of applications such as medical, industrial, and space research. We present the spectroscopic properties of some CZT crystals grown by the standard vertical Bridgman method and by the boron oxide encapsulated vertical Bridgman method, which has been recently implemented at IMEM-CNR (Parma, Italy). In this technique, the crystal is grown in an open quartz crucible fully encapsulated by a thin layer of liquid boron oxide. This method prevents contact between the crystal and the crucible, thereby allowing larger single grains with a lower dislocation density to be obtained. Several mono-electrode detectors were realized, with each having two planar gold contacts. The samples are characterized by an active area of about 7 mm x 7 mm and thicknesses ranging from 1 to 2 mm. The charge transport properties of the detectors have been studied by mobility-lifetime ({mu} x {tau}) product measurements, carried out at the European Synchrotron Radiation Facility (Grenoble, France) in the planar transverse field configuration, where the impinging beam direction is orthogonal to the collecting electric field. We have performed several fine scans between the electrodes with a beam spot of 10 {mu}m x 10 {mu}m at various energies from 60 to 400 keV. In this work, we present the test results in terms of the ({mu} x {tau}) product of both charge carriers.

Auricchio, N.; Caroli, E. [INAF/IASF-Bologna, Bologna, 40129 (Italy); Marchini, L.; Zappettini, A. [IMEM-CNR, Parma, 43100 (Italy); Abbene, L. [DIFI, University of Palermo, Palermo, 90128 (Italy); Honkimaki, V. [European Synchrotron Radiation Facility, Grenoble, 38000 (France)

2011-12-15T23:59:59.000Z

295

Recent results with a CdTe imaging portal scanner for radiation therapy  

SciTech Connect

One of the most promising means for improving the quality of radiation therapy is the use of real-time imaging systems for routine portal position verification. The authors have constructed a prototype portal imager using a linear array of 256 CdTe photovoltaic detectors, each 2X2X2 mm. The array is attached to a compact linear scanner which is to be mounted in a cassette shaped package located below the patient table. The array of detectors is moved under the patient during image acquisition. The high stopping power of the CdTe allows a high contrast image to be made using a single linac pulse for each array position. In tests conducted with a 4 MV linac, this system produced 50 cm x 35 cm images with an open field signal-to-noise ratio of 143 and 2 mm spatial resolution in less than 3 seconds. This corresponds to a signal-to-noise ratio of 1 for 1% contrast objects. Ultimately, a signal-to-noise ratio greater than 5 at 1% contrast should be achievable with no loss of spatial resolution or increase in acquisition time.

Entine, G.; Redus, R.H.; Feyder, A. (Radiation Monitoring Devices, Inc., Watertown, MA (United States)); Biggs, P.J. (Massachusetts General Hospital, Boston, MA (United States))

1993-08-01T23:59:59.000Z

296

Formation of ohmic contacts to low-resistivity Cd{sub 1-x}Mg{sub x}Te alloys for photovolatic applications  

SciTech Connect

Electrical properties of the Cd{sub 1-x}Mg{sub x} Te alloys of various composition (0.1 {<=} x {<=} 0.3) are studied. It is established that at x = 0.1, a low-resistivity p-type material with parameters close to undoped CdTe is formed. A feature of the Cd{sub 0.9}Mg{sub 0.1} Te crystals is that, during deposition of Cu on their surface from a saturated CuSO{sub 4} solution, ohmic contact is formed, the characteristics of which do not worsen in a wide temperature range (80-300 K). The study of characteristics with and without illumination of the Cu/p-Cd{sub 0.9}Mg{sub 0.1}Te/n-Cd{sub 0.9}Mg{sub 0.1}Te/In structures have shown that they are promising as photoconverters of solar radiation.

Parfenyuk, O. A., E-mail: parfenyuk@chnu.cv.ua; Ilashchuk, M. I.; Ulyanitsky, K. S. [Fed'kovich National University (Ukraine)

2008-11-15T23:59:59.000Z

297

LOWER LIMITS ON ULTRAHIGH-ENERGY COSMIC RAY AND JET POWERS OF TeV BLAZARS  

Science Conference Proceedings (OSTI)

Lower limits on the power emitted in ultrahigh-energy cosmic rays (UHECRs), which are assumed to be protons with energy {approx}> 10{sup 17}-10{sup 20} eV, are derived for TeV blazars with the assumption that the observed TeV {gamma}-rays are generated due to interactions of these protons with cosmic microwave photons. The limits depend on the spectrum of the injected UHECR protons. While for a -2.2 injection spectrum the lower limits on the powers emitted in UHECRs by 1ES 0229+200, 1ES 1101-232, and 1ES 0347-121 are lower than their respective synchrotron luminosities ({approx}10{sup 46} erg s{sup -1}), in the case of 1ES 1426+428 it exceeds the corresponding synchrotron luminosity by up to an order of magnitude. The proposed Auger North Observatory should be able to detect 4 Multiplication-Sign 10{sup 19} eV cosmic-ray (CR) protons from 1ES 1426+428 within a few years of operation and test the TeV {gamma}-ray production model by UHECR energy losses while propagating along the line of sight or constrain the intergalactic magnetic field to be larger than {approx}10{sup -16} G in case of no detection. The lower limits on the apparent-isotropic jet power from accelerated 10{sup 10}-10{sup 20} eV proton spectra in the blazar jet is of the order of the Eddington luminosity of a 10{sup 9} M{sub Sun} black hole for a CR injection spectrum -2.2 or harder for all blazars considered except for 1ES 1426+428. In the case of the latter, the apparent-isotropic jet power exceeds the Eddington luminosity by an order of magnitude. For an injection spectrum softer than -2.2, as is required to fit the observed CR data above {approx}10{sup 17}-10{sup 18} eV, the Eddington luminosity is exceeded by the lower limits on the jet power for all blazars considered.

Razzaque, Soebur [School of Physics, Astronomy and Computational Sciences, George Mason University, Fairfax, VA 22030 (United States); Dermer, Charles D.; Finke, Justin D., E-mail: srazzaqu@gmu.edu [Space Science Division, US Naval Research Laboratory, Washington, DC 20375 (United States)

2012-02-01T23:59:59.000Z

298

Observation of an Anisotropy in the Galactic Cosmic Ray arrival direction at 400 TeV with IceCube  

E-Print Network (OSTI)

In this paper we report the first observation in the Southern hemisphere of an energy dependence in the Galactic cosmic ray anisotropy up to a few hundred TeV. This measurement was performed using cosmic ray induced muons recorded by the partially deployed IceCube observatory between May 2009 and May 2010. The data include a total of 33$\\times 10^{9}$ muon events with a median angular resolution of $\\sim3^{\\circ}$ degrees. A sky map of the relative intensity in arrival direction over the Southern celestial sky is presented for cosmic ray median energies of 20 and 400 TeV. The same large-scale anisotropy observed at median energies around 20 TeV is not present at 400 TeV. Instead, the high energy skymap shows a different anisotropy structure including a deficit with a post-trial significance of -6.3$\\sigma$. This anisotropy reveals a new feature of the Galactic cosmic ray distribution, which must be incorporated into theories of the origin and propagation of cosmic rays.

IceCube Collaboration; R. Abbasi; Y. Abdou; T. Abu-Zayyad; M. Ackermann; J. Adams; J. A. Aguilar; M. Ahlers; M. M. Allen; D. Altmann; K. Andeen; J. Auffenberg; X. Bai; M. Baker; S. W. Barwick; R. Bay; J. L. Bazo Alba; K. Beattie; J. J. Beatty; S. Bechet; J. K. Becker; K. -H. Becker; M. L. Benabderrahmane; S. BenZvi; J. Berdermann; P. Berghaus; D. Berley; E. Bernardini; D. Bertrand; D. Z. Besson; D. Bindig; M. Bissok; E. Blaufuss; J. Blumenthal; D. J. Boersma; C. Bohm; D. Bose; S. Bser; O. Botner; A. M. Brown; S. Buitink; K. S. Caballero-Mora; M. Carson; D. Chirkin; B. Christy; F. Clevermann; S. Cohen; C. Colnard; D. F. Cowen; A. H. Cruz Silva; M. V. D'Agostino; M. Danninger; J. Daughhetee; J. C. Davis; C. De Clercq; T. Degner; L. Demirrs; F. Descamps; P. Desiati; G. de Vries-Uiterweerd; T. DeYoung; J. C. Daz-Vlez; M. Dierckxsens; J. Dreyer; J. P. Dumm; M. Dunkman; J. Eisch; R. W. Ellsworth; O. Engdegrd; S. Euler; P. A. Evenson; O. Fadiran; A. R. Fazely; A. Fedynitch; J. Feintzeig; T. Feusels; K. Filimonov; C. Finley; T. Fischer-Wasels; B. D. Fox; A. Franckowiak; R. Franke; T. K. Gaisser; J. Gallagher; L. Gerhardt; L. Gladstone; T. Glsenkamp; A. Goldschmidt; J. A. Goodman; D. Gra; D. Grant; T. Griesel; A. Gro; S. Grullon; M. Gurtner; C. Ha; A. Haj Ismail; A. Hallgren; F. Halzen; K. Han; K. Hanson; D. Heinen; K. Helbing; R. Hellauer; S. Hickford; G. C. Hill; K. D. Hoffman; B. Hoffmann; A. Homeier; K. Hoshina; W. Huelsnitz; J. -P. Hl; P. O. Hulth; K. Hultqvist; S. Hussain; A. Ishihara; E. Jacobi; J. Jacobsen; G. S. Japaridze; H. Johansson; K. -H. Kampert; A. Kappes; T. Karg; A. Karle; P. Kenny; J. Kiryluk; F. Kislat; S. R. Klein; J. -H. Khne; G. Kohnen; H. Kolanoski; L. Kpke; S. Kopper; D. J. Koskinen; M. Kowalski; T. Kowarik; M. Krasberg; G. Kroll; N. Kurahashi; T. Kuwabara; M. Labare; K. Laihem; H. Landsman; M. J. Larson; R. Lauer; J. Lnemann; J. Madsen; A. Marotta; R. Maruyama; K. Mase; H. S. Matis; K. Meagher; M. Merck; P. Mszros; T. Meures; S. Miarecki; E. Middell; N. Milke; J. Miller; T. Montaruli; R. Morse; S. M. Movit; R. Nahnhauer; J. W. Nam; U. Naumann; D. R. Nygren; S. Odrowski; A. Olivas; M. Olivo; A. O'Murchadha; S. Panknin; L. Paul; C. Prez de los Heros; J. Petrovic; A. Piegsa; D. Pieloth; R. Porrata; J. Posselt; C. C. Price; P. B. Price; G. T. Przybylski; K. Rawlins; P. Redl; E. Resconi; W. Rhode; M. Ribordy; M. Richman; J. P. Rodrigues; F. Rothmaier; C. Rott; T. Ruhe; D. Rutledge; B. Ruzybayev; D. Ryckbosch; H. -G. Sander; M. Santander; S. Sarkar; K. Schatto; T. Schmidt; A. Schnwald; A. Schukraft; A. Schultes; O. Schulz; M. Schunck; D. Seckel; B. Semburg; S. H. Seo; Y. Sestayo; S. Seunarine; A. Silvestri; G. M. Spiczak; C. Spiering; M. Stamatikos; T. Stanev; T. Stezelberger; R. G. Stokstad; A. Stl; E. A. Strahler; R. Strm; M. Ster; G. W. Sullivan; Q. Swillens; H. Taavola; I. Taboada; A. Tamburro; A. Tepe; S. Ter-Antonyan; S. Tilav; P. A. Toale; S. Toscano; D. Tosi; N. van Eijndhoven; J. Vandenbroucke; A. Van Overloop; J. van Santen; M. Vehring; M. Voge; C. Walck; T. Waldenmaier; M. Wallraff; M. Walter; Ch. Weaver; C. Wendt; S. Westerhoff; N. Whitehorn; K. Wiebe; C. H. Wiebusch; D. R. Williams; R. Wischnewski; H. Wissing; M. Wolf; T. R. Wood; K. Woschnagg; C. Xu; D. L. Xu; X. W. Xu; J. P. Yanez; G. Yodh; S. Yoshida; P. Zarzhitsky; M. Zoll

2011-09-05T23:59:59.000Z

299

Measurement of the isolated diphoton cross section in pp collisions at ?s=7??TeV with the ATLAS detector  

E-Print Network (OSTI)

The ATLAS experiment has measured the production cross section of events with two isolated photons in the final state, in proton-proton collisions at ?s=7??TeV. The full data set acquired in 2010 is used, corresponding to ...

Taylor, Frank E.

300

OBSERVATION OF TeV GAMMA RAYS FROM THE CYGNUS REGION WITH THE ARGO-YBJ EXPERIMENT  

SciTech Connect

We report the observation of TeV {gamma}-rays from the Cygnus region using the ARGO-YBJ data collected from 2007 November to 2011 August. Several TeV sources are located in this region including the two bright extended MGRO J2019+37 and MGRO J2031+41. According to the Milagro data set, at 20 TeV MGRO J2019+37 is the most significant source apart from the Crab Nebula. No signal from MGRO J2019+37 is detected by the ARGO-YBJ experiment, and the derived flux upper limits at the 90% confidence level for all the events above 600 GeV with medium energy of 3 TeV are lower than the Milagro flux, implying that the source might be variable and hard to be identified as a pulsar wind nebula. The only statistically significant (6.4 standard deviations) {gamma}-ray signal is found from MGRO J2031+41, with a flux consistent with the measurement by Milagro.

Bartoli, B.; Catalanotti, S. [Dipartimento di Fisica dell'Universita di Napoli 'Federico II', Complesso Universitario di Monte Sant'Angelo, via Cinthia, 80126 Napoli (Italy); Bernardini, P.; Bleve, C. [Dipartimento di Fisica dell'Universita del Salento, via per Arnesano, 73100 Lecce (Italy); Bi, X. J.; Cao, Z.; Chen, S. Z.; Chen, Y. [Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, P.O. Box 918, 100049 Beijing (China); Bolognino, I. [Dipartimento di Fisica Nucleare e Teorica dell'Universita di Pavia, via Bassi 6, 27100 Pavia (Italy); Branchini, P.; Budano, A. [Istituto Nazionale di Fisica Nucleare, Sezione di Roma Tre, via della Vasca Navale 84, 00146 Roma (Italy); Calabrese Melcarne, A. K. [Istituto Nazionale di Fisica Nucleare-CNAF, Viale Berti-Pichat 6/2, 40127 Bologna (Italy); Camarri, P. [Dipartimento di Fisica dell'Universita di Roma 'Tor Vergata', via della Ricerca Scientifica 1, 00133 Roma (Italy); Cardarelli, R. [Istituto Nazionale di Fisica Nucleare, Sezione di Roma Tor Vergata, via della Ricerca Scientifica 1, 00133 Roma (Italy); Cattaneo, C. [Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, via Bassi 6, 27100 Pavia (Italy); Chen, T. L. [Tibet University, 850000 Lhasa, Xizang (China); Creti, P. [Istituto Nazionale di Fisica Nucleare, Sezione di Lecce, via per Arnesano, 73100 Lecce (Italy); Cui, S. W. [Hebei Normal University, Shijiazhuang 050016, Hebei (China); Dai, B. Z. [Yunnan University, 2 North Cuihu Road, 650091 Kunming, Yunnan (China); D'Ali Staiti, G., E-mail: chensz@ihep.ac.cn [Dipartimento di Fisica e Tecnologie Relative, Universita degli Studi di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo (Italy); Collaboration: ARGO-YBJ Collaboration; and others

2012-02-15T23:59:59.000Z

Note: This page contains sample records for the topic "graphi te hoback" from the National Library of EnergyBeta (NLEBeta).
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to obtain the most current and comprehensive results.


301

Probing the Era of Galaxy Formation via TeV Gamma Ray Absorption by the Near Infrared Extragalactic Background  

E-Print Network (OSTI)

We present models of the extragalactic background light (EBL) based on several scenarios of galaxy formation and evolution. We have treated galaxy formation with the Press-Schecter approximation for both cold dark matter (CDM) and cold+hot dark matter (CHDM) models, representing a moderate ($z_f \\sim 3$) and a late ($z_f \\sim 1$) era of galaxy formation respectively. Galaxy evolution has been treated by considering a variety of stellar types, different initial mass functions and star formation histories, and with an accounting of dust absorption and emission. We find that the dominant factor influencing the EBL is the epoch of galaxy formation. A recently proposed method for observing the EBL utilizing the absorption of $\\sim 0.1$ to 10 TeV gamma-rays from active galactic nuclei (AGN) is shown to be capable of discriminating between different galaxy formation epochs. The one AGN viewed in TeV light, Mrk 421, does show some evidence for a cutoff above 3 TeV; based on the EBL models presented here, we suggest that this is due to extinction in the source. The large absorption predicted at energies $>200$ GeV for sources at $z>0.5$ indicates that observations of TeV gamma-ray bursts (GRB) would constrain or eliminate models in which the GRB sources lie at cosmological distances.

D. MacMinn; J. R. Primack

1995-04-11T23:59:59.000Z

302

Study of Baryonic R-Parity Violating MSSM Using Jet Substructure Technique at the 14 TeV LHC  

E-Print Network (OSTI)

We study the discovery reach of the gluino ($\\widetilde{g}$) and the lightest stop squark ($\\widetilde{t}_1$) with baryonic R-parity violation (UDD type) in the context of Minimal Supersymmetric Standard Model (MSSM) at the 14 TeV run of the LHC. We consider the gluino pair production process followed by its decay to a top quark and a real or virtual stop squark. The top quark produced from the decay of the gluino can have sufficient transverse momentum to appear as a single fat jet. We apply the jet substructure technique to tag such a hadronically decaying boosted top quark and find that gluino mass up to 1.6 TeV can be discovered whereas exclusion limit extends up to 1.8 TeV at the 14 TeV LHC with 300 $\\rm fb^{-1}$ luminosity. We also briefly discuss the discovery prospect of the boosted stop squark which may be identified as a narrow resonance in the jet mass distribution.

Bhattacherjee, Biplob

2013-01-01T23:59:59.000Z

303

Synchrotron radiation x-ray absorption fine-structure and Raman studies on CdZnTe ternary alloys  

E-Print Network (OSTI)

The synchrotron radiation (SR) X-ray absorption fine-structure spectroscopy (XAFS) technology has been employed to obtained Zn K-edge absorption spectra for Cd1[subscript 1-x]Zn[subscript x]Te alloy with x = 0.03, 0.10, ...

Becla, Piotr

304

TIME DELAY OF CASCADE RADIATION FOR TeV BLAZARS AND THE MEASUREMENT OF THE INTERGALACTIC MAGNETIC FIELD  

SciTech Connect

Recent claims that the strength B{sub IGMF} of the intergalactic magnetic field (IGMF) is {approx}> 10{sup -15} G are based on upper limits to the expected cascade flux in the GeV band produced by blazar TeV photons absorbed by the extragalactic background light. This limit depends on an assumption that the mean blazar TeV flux remains constant on timescales {approx}> 2(B{sub IGMF}/10{sup -18}G){sup 2}/(E/10 GeV){sup 2} yr for an IGMF coherence length {approx}1 Mpc, where E is the measured photon energy. Restricting TeV activity of 1ES 0229+200 to {approx}3-4 years during which the source has been observed leads to a more robust lower limit of B{sub IGMF} {approx}> 10{sup -18} G, which can be larger by an order of magnitude if the intrinsic source flux above {approx}5-10 TeV from 1ES 0229+200 is strong.

Dermer, Charles D.; Razzaque, Soebur; Finke, Justin D. [Space Science Division, U.S. Naval Research Laboratory, Washington, DC 20375 (United States); Cavadini, Massimo [Dipartimento di Fisica e Matematica, Universita dell'Insubria, via Valleggio 11, 22100, Como (Italy); Chiang, James [W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States); Lott, Benoit, E-mail: charles.dermer@nrl.navy.mil [CNRS/IN2P3, Centre d' Etudes Nucleaires Bordeaux Gradignan, UMR 5797, Gradignan, 33175 (France)

2011-06-01T23:59:59.000Z

305

A measurement of the 2 neutrino double beta decay rate of Te-130 in the CUORICINO experiment  

Science Conference Proceedings (OSTI)

CUORICINO was a cryogenic bolometer experiment designed to search for neutrinoless double beta decay and other rare processes, including double beta decay with two neutrinos (2{nu}{beta}{beta}). The experiment was located at Laboratori Nazionali del Gran Sasso and ran for a period of about 5 years, from 2003 to 2008. The detector consisted of an array of 62 TeO{sub 2} crystals arranged in a tower and operated at a temperature of #24;10 mK. Events depositing energy in the detectors, such as radioactive decays or impinging particles, produced thermal pulses in the crystals which were read out using sensitive thermistors. The experiment included 4 enriched crystals, 2 enriched with {sup 130}Te and 2 with {sup 128}Te, in order to aid in the measurement of the 2{nu}{beta}{beta} rate. The enriched crystals contained a total of #24;350 g {sup 130}Te. The 128-enriched (130-depleted) crystals were used as background monitors, so that the shared backgrounds could be subtracted from the energy spectrum of the 130- enriched crystals. Residual backgrounds in the subtracted spectrum were fit using spectra generated by Monte-Carlo simulations of natural radioactive contaminants located in and on the crystals. The 2{nu}{beta}{beta} half-life was measured to be T{sup 2{nu}}{sub 1/2} = [9.81{+-} #6;0.96(stat){+-} 0.49(syst)]#2;x10{sup 20} y.

Kogler, Laura

2011-11-03T23:59:59.000Z

306

Effect of Al(OH)3 on the hydrogen generation of aluminumewater system Hsin-Te Teng a  

E-Print Network (OSTI)

Effect of Al(OH)3 on the hydrogen generation of aluminumewater system Hsin-Te Teng a , To-Ying Lee effect of Al(OH)3 powders on Al/H2O system for hydrogen generation was demonstrated. crystalline Al(OH)3 powder acts an effective additive to the Al/H2O system.

Cao, Guozhong

307

Measurement of inclusive jet and dijet production in pp collisions at ?s=7??TeV using the ATLAS detector  

E-Print Network (OSTI)

Inclusive jet and dijet cross sections have been measured in proton-proton collisions at a center-of-mass energy of 7 TeV using the ATLAS detector at the Large Hadron Collider. The cross sections were measured using jets ...

Taylor, Frank E.

308

BLAZARS AS ULTRA-HIGH-ENERGY COSMIC-RAY SOURCES: IMPLICATIONS FOR TeV GAMMA-RAY OBSERVATIONS  

Science Conference Proceedings (OSTI)

The spectra of BL Lac objects and Fanaroff-Riley I radio galaxies are commonly explained by the one-zone leptonic synchrotron self-Compton (SSC) model. Spectral modeling of correlated multiwavelength data gives the comoving magnetic field strength, the bulk outflow Lorentz factor, and the emission region size. Assuming the validity of the SSC model, the Hillas condition shows that only in rare cases such sources accelerate protons to much above 10{sup 19} eV, so {approx}> 10{sup 20} eV ultra-high-energy cosmic rays (UHECRs) are likely to be heavy ions if powered by this type of radio-loud active galactic nuclei (AGNs). Survival of nuclei is shown to be possible in TeV BL Lacs and misaligned counterparts with weak photohadronic emissions. Another signature of hadronic production is intergalactic UHECR-induced cascade emission, which is an alternative explanation of the TeV spectra of some extreme non-variable blazars such as 1ES 0229+200 or 1ES 1101-232. We study this kind of cascade signal, taking into account effects of the structured extragalactic magnetic fields in which the sources should be embedded. We demonstrate the importance of cosmic-ray deflections on the {gamma}-ray flux, and show that required absolute cosmic-ray luminosities are larger than the average UHECR luminosity inferred from UHECR observations and can even be comparable to the Eddington luminosity of supermassive black holes. Future TeV {gamma}-ray observations using the Cerenkov Telescope Array and the High Altitude Water Cerenkov detector array can test for UHECR acceleration by observing >25 TeV photons from relatively low redshift sources such as 1ES 0229+200, and {approx}>TeV photons from more distant radio-loud AGNs.

Murase, Kohta [Department of Physics, Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210 (United States); Dermer, Charles D. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Takami, Hajime [Max Planck Institute for Physics, Foehringer Ring 6, 80805 Munich (Germany); Migliori, Giulia [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

2012-04-10T23:59:59.000Z

309

Emerging materials for solar cell applications: electrodeposited CdTe. Final report, February 14, 1979-February 14, 1980  

DOE Green Energy (OSTI)

Thin film gold/polycrystalline cadmium telluride Schottky solar cells made by electrodepositing the semiconductor on an ITO-coated glass substrate serving also as an ohmic contact demonstrated an internal efficiency of 4% over 2 mm/sup 2/ areas. During the year being reported upon, Monosolar devoted mator attention to refining the electroplating process and determining the parameters governing CdTe film stoichiometry, grain size, substrate adhesion, and quality. UCLA acting as a Monosolar sub-contractor characterized both the CdTe films themselves and solar cells made from them. Techniques were developed for making measurements on films often less than 1 micron in thickness. The highest values achieved for efficiency parameters, not necessarily all in the same cell, were V/sub oc/ = 0.5 V, J/sub sc/ = 11 mA/cm/sup 2/, and fill factor = 0.55 before corrections in the absence of anti-reflection coatings. Typical resistivities for n-CdTe films were 10/sup 5/ ..cap omega..-cm. Lifetimes of about 10/sup -10/ sec were measured. Absorption coefficient of these films is in the order of 10/sup 4/ for lambda < 0.7 ..mu..m. Measured energy gap for these CdTe films is 1.55 eV, sightly higher than the 1.45 eV value for single crystal CdTe. The activation energy of the dominating trap level is 0.55 eV. Trap density is in the order of 10/sup 16//cm/sup 3/. Schottky diodes were of excellent quality and pinhole-free. The measured barrier height varied between 0.75 and 0.85 eV. Rectification ratios of 10/sup 4/ were obtained reproducibly. Films measure about 1 inch square. Indications are that larger and more efficient low cost solar devices can readily be obtained soon using the techniques developed in this program.

Rod, R.L.; Bunshah, R.; Stafsudd, O.; Basol, B.M.; Nath, P.

1980-05-15T23:59:59.000Z

310

Appendix B: CArBon dioxide CApture teChnology SheetS  

NLE Websites -- All DOE Office Websites (Extended Search)

membranes membranes B-370 Post-Combustion membranes u.s. DePartment of energy aDvanCeD Carbon DioxiDe CaPture r&D Program: teChnology uPDate, may 2013 eleCtroChemiCal membrane for Carbon DioxiDe CaPture & Power generation primary project goals FuelCell Energy, Inc. (FCE) is developing an electrochemical membrane (ECM)-based Combined Electric Power and Carbon Dioxide Separation (CEPACS) system for carbon dioxide (CO 2 ) capture that also provides additional electrical power generation. The project includes bench-scale testing of an 11.7 m 2 -area ECM (molten carbonate fuel cell) system for CO 2 capture, purification, and compression. technical goals * Perform contaminant effect testing to establish maximum permissible concentrations of

311

Commercial production of thin-film CdTe photovoltaic modules. 1995 annual report  

DOE Green Energy (OSTI)

This report presents a general overview of progress made in Golden Photon Inc.`s commercial production of thin-film CdTe photovoltaic modules. It describes the improvement in the number of batch runs processed through substrate deposition, all inter-connection, and encapsulation process steps; a progressive increase in the total number of panels processed each month; an improvement in cumulative process yields; and the continual attention given to modifying operating parameters of each major process step. The report also describes manpower status and staffing issues. The description of the status of subcontract progress includes engineering design; process improvement and development; cost improvement and raw materials; environment, safety, and health; and manufacturing cost and productivity optimization. Milestones and deliverables are also described.

Brog, T.K. [Golden Photon, Inc., CO (United States)

1997-02-01T23:59:59.000Z

312

Direct Observation of Room-Temperature Polar Ordering in Colloidal GeTe Nanocrystals  

SciTech Connect

Ferroelectrics and other materials that exhibit spontaneous polar ordering have demonstrated immense promise for applications ranging from non-volatile memories to microelectromechanical systems. However, experimental evidence of polar ordering and effective synthetic strategies for accessing these materials are lacking for low-dimensional nanomaterials. Here, we demonstrate the synthesis of size-controlled nanocrystals of the polar material germanium telluride (GeTe) using colloidal chemistry and provide the first direct evidence of room-temperature polar ordering in nanocrystals less than 5 nm in size using aberration-corrected transmission electron microscopy. Synchrotron x-ray diffraction and Raman studies demonstrate a sizeable polar distortion and a reversible size-dependent polar phase transition in these nanocrystals. The stability of polar ordering in solution-processible nanomaterials suggests an economical avenue to Tbit/in2-density non-volatile memory devices and other applications.

Polking, Mark J.; Zheng, Haimei; Urban, Jeffrey J.; Milliron, Delia J.; Chan, Emory; Caldwell, Marissa A.; Raoux, Simone; Kisielowski, Christian F.; Ager III, Joel W.; Ramesh, Ramamoorthy; Alivisatos, A.P.

2009-12-07T23:59:59.000Z

313

LLNL 10(a)(1)(A) Annual Report (TE-053672-2)--2005  

SciTech Connect

This report summarizes research related to Lawrence Livermore National Laboratory's (LLNL) Experimental Test Site, Site 300 (S300), located within Alameda and San Joaquin Counties (Figure 1) and conducted under the 10(a)(1)(A) (Recovery) permit TE-053672-2. This property is held in ownership by the U.S. Department of Energy/National Nuclear Security Administration (NNSA). The 2005 Recovery research at S300 involved fieldwork associated with only two species: Alameda whipsnake (Masticophis lateralis euryxanthus) and the California red-legged frog (Rana aurora draytonii) (RLF). Note: the whipsnake subspecies existing at S300 shows taxonomic variation (generally 50% chaparral whipsnake [Masticophis lateralis] traits) when compared to the Alameda whipsnake (Riemer 1954) and therefore it will be referred to as ''California whipsnake (Masticophis lateralis)'' (CWS) for classification purposes in this report (Swaim 2004).

Woollett, J

2006-01-26T23:59:59.000Z

314

Appendix B: CArBon dioxide CApture teChnology SheetS  

NLE Websites -- All DOE Office Websites (Extended Search)

solvents solvents B-6 Pre-Combustion solvents u.s. DePartment of energy aDvanCeD Carbon DioxiDe CaPture r&D Program: teChnology uPDate, may 2013 Co 2 CaPture from igCC gas streams using aC-abC ProCess primary project goals SRI International is developing, for integrated gasification combined cycle (IGCC)-based power plants, a carbon dioxide (CO 2 ) capture technology based on the use of a high-ca- pacity and low-cost aqueous ammoniated solution containing ammonium carbonate (AC), which reacts with CO 2 to form ammonium bicarbonate (ABC).

315

Appendix B: CArBon dioxide CApture teChnology SheetS  

NLE Websites -- All DOE Office Websites (Extended Search)

solvents solvents B-198 Post-Combustion solvents u.s. DePartment of energy aDvanCeD Carbon DioxiDe CaPture r&D Program: teChnology uPDate, may 2013 DeveloPment anD Demonstration of Waste heat integration With solvent ProCess for more effiCient Co 2 removal from Coal-fireD flue gas primary project goals Southern Company Services is developing viable heat integration methods for the capture of carbon dioxide (CO 2 ) produced from pulverized coal (PC) combustion. The project will quantify energy-efficiency improvements to the CO 2 capture process by utilizing a waste heat recovery technology, High-Efficiency System (HES). technical goals * Reduction of the amount of extraction steam required for sensible heat load in the

316

Appendix B: CArBon dioxide CApture teChnology SheetS  

NLE Websites -- All DOE Office Websites (Extended Search)

sorbents sorbents B-302 Post-Combustion sorbents u.s. DePartment of energy aDvanCeD Carbon DioxiDe CaPture r&D Program: teChnology uPDate, may 2013 benCh-sCale DeveloPment anD testing of raPiD Pressure swing absorPtion for Carbon DioxiDe CaPture primary project goals WR Grace and the University of South Carolina are developing a rapid pressure swing adsorption (PSA) process to evaluate concept cost and performance benefits by testing a bench-scale system using a low-cost, structured adsorbent with low-pressure drop, high mass-transfer rates, high capacity, and high availability that will enable large feed through- puts. technical goals * Develop an attrition-resistant and low-pressure drop structured adsorbent based on a

317

Exploring the powering source of the TeV X-ray binary LS 5039  

E-Print Network (OSTI)

LS 5039 is one of the four TeV emitting X-ray binaries detected up to now. The powering source of its multi-wavelength emission can be accretion in a microquasar scenario or wind interaction in a young non-accreting pulsar scenario. These two scenarios predict different morphologic and peak position changes along the orbital cycle of 3.9 days, which can be tested at milliarcsecond scales using VLBI techniques. Here we present a campaign of 5 GHz VLBA observations conducted in June 2000 (2 runs five days apart). The results show a core component with a constant flux density, and a fast change in the morphology and the position angle of the elongated extended emission, but maintaining a stable flux density. These results are difficult to fit comfortably within a microquasar scenario, whereas they appear to be compatible with the predicted behavior for a non-accreting pulsar.

J. Moldon; M. Ribo; Josep M. Paredes; J. Marti; M. Massi

2008-12-04T23:59:59.000Z

318

The TeV Energy Spectrum of Mrk 421 Measured in A High Flaring State  

E-Print Network (OSTI)

The BL Lac object (blazar) Mrk 421 was observed during its outburst in April 2004 with the Whipple 10 m telescope for a total of about 24.5 hours. The measured gamma-ray rate varied substantially over the range from 4 to 10 gamma's/min and eventually exceeded the steady gamma-ray rate of the Crab Nebula (standard candle) by a factor of 3. The overall significance of the gamma-ray signal exceeded 70 sigma and the total number of excess events was more than 10,000. The signal light curve does not show any particular variability pattern. This unique Mrk 421 outburst enabled the measurement of a high quality spectrum of very high-energy gamma rays in a high state of emission. This spectrum is a power-law and it extends beyond 10 TeV.

A. Konopelko; W. Cui; C. Duke; J. P. Finley

2007-08-28T23:59:59.000Z

319

Jet structure in 2.76 TeV Pb Pb collisions at ALICE  

E-Print Network (OSTI)

We present the analysis of the semi-inclusive distribution of reconstructed charged particle jets recoiling from a high pT hadron trigger in central Pb Pb collisions at $\\sqrt{s_{NN}}=2.76$ TeV. We measure, subtract and unfold the large underlying event background in such collisions, utilizing a novel technique that does not impose fragmentation bias on the measured jet population. The Pb Pb measurements are compared to a pp PYTHIA reference distribution generated at the same $\\sqrt{s}$. Modification of jet structure due to quenching is explored by varying the cone radius $R$ (0.2, 0.4) and the lower pT cutoff of charged particle constituents (0.15, 2.0 GeV/$c$).

ALICE Collaboration

2012-10-29T23:59:59.000Z

320

Sensitivity of an underwater Cerenkov km3 telescope to TeV neutrinos from Galactic Microquasars  

E-Print Network (OSTI)

In this paper are presented the results of Monte Carlo simulations on the capability of the proposed NEMO-km$^3$ telescope to detect TeV muon neutrinos from Galactic microquasars. For each known microquasar we compute the number of detectable events, together with the atmospheric neutrino and muon background events. We also discuss the detector sensitivity to neutrino fluxes expected from known microquasars, optimizing the event selection also to reject the background; the number of events surviving the event selection are given. The best candidates are the steady microquasars SS433 and GX339-4 for which we estimate a sensitivity of about $5\\cdot10^{-11}$ erg/cm$^2$ s; the predicted fluxes are expected to be well above this sensitivity. For bursting microquasars the most interesting candidates are Cygnus X-3, GRO J1655-40 and XTE J1118+480: their analyses are more complicated because of the stochastic nature of the bursts.

C. Distefano; the NEMO Collaboration

2006-08-02T23:59:59.000Z

Note: This page contains sample records for the topic "graphi te hoback" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Baryon and lepton number violation in the electroweak theory at TeV energies  

Science Conference Proceedings (OSTI)

In the standard Weinberg-Salam electroweak theory baryon and lepton number (B and L) are NOT exactly conserved. The nonconservation of B and L can be traced to the existence of parity violation in the electroweak theory, together with the chiral current anomaly. This subtle effect gives negligibly small amplitudes for B and L violation at energies and temperatures significantly smaller than M{sub w} sin{sup 2} {theta}{sub w}/{alpha} {approximately} 10 TeV. However, recent theoretical work shows that the rate for B and L nonconservation is unsuppressed at higher energies. The consequences of this for cosmology and the baryon asymmetry of the universe, as well as the prospects for direct verification at the SSC are discussed. 13 refs., 3 figs.

Mottola, E.

1990-01-01T23:59:59.000Z

322

Fermi Surface Evolution Across Multiple Charge Density Wave Transitions in ErTe3  

Science Conference Proceedings (OSTI)

The Fermi surface (FS) of ErTe{sub 3} is investigated using angle-resolved photoemission spectroscopy (ARPES). Low temperature measurements reveal two incommensurate charge density wave (CDW) gaps created by perpendicular FS nesting vectors. A large {Delta}{sub 1} = 175 meV gap arising from a CDW with c* - q{sub CDW1} {approx} 0.70(0)c* is in good agreement with the expected value. A second, smaller {Delta}{sub 2} = 50 meV gap is due to a second CDW with a* - q{sub CDW2} {approx} 0.68(5)a*. The temperature dependence of the FS, the two gaps and possible interaction between the CDWs are examined.

Moore, R.G.; /SLAC, SSRL /Stanford U., Geballe Lab.; Brouet, V.; /Orsay, LPS; He, R.; /SLAC, SSRL /Stanford U., Geballe Lab.; Lu, D.H.; /SLAC, SSRL; Ru, N.; Chu, J.-H.; Fisher, I.R.; /Stanford U., Geballe Lab.; Shen, Z.-X.; /SLAC, SSRL /Stanford U., Geballe Lab.

2010-02-15T23:59:59.000Z

323

Analytical model for event reconstruction in coplanar grid CdZnTe detectors  

E-Print Network (OSTI)

Coplanar-grid (CPG) particle detectors were designed for materials such as CdZnTe (CZT) in which charge carriers of only one sign have acceptable transport properties. The presence of two independent anode signals allows for a reconstruction of deposited energy based on the difference between the two signals, and a reconstruction of the interaction depth based on the ratio of the amplitudes of the sum and difference of the signals. Energy resolution is greatly improved by modifying the difference signal with an empirically determined weighting factor to correct for the effects of electron trapping. In this paper is introduced a modified interaction depth reconstruction formula which corrects for electron trapping utilizing the same weighting factor used for energy reconstruction. The improvement of this depth reconstruction over simpler formulas is demonstrated. Further corrections due to the contribution of hole transport to the signals are discussed.

Matthew Fritts; Jrgen Durst; Thomas Gpfert; Thomas Wester; Kai Zuber

2012-11-28T23:59:59.000Z

324

Analytical model for event reconstruction in coplanar grid CdZnTe detectors  

E-Print Network (OSTI)

Coplanar-grid (CPG) particle detectors were designed for materials such as CdZnTe (CZT) in which charge carriers of only one sign have acceptable transport properties. The presence of two independent anode signals allows for a reconstruction of deposited energy based on the difference between the two signals, and a reconstruction of the interaction depth based on the ratio of the amplitudes of the sum and difference of the signals. Energy resolution is greatly improved by modifying the difference signal with an empirically determined weighting factor to correct for the effects of electron trapping. In this paper is introduced a modified interaction depth reconstruction formula which corrects for electron trapping utilizing the same weighting factor used for energy reconstruction. The improvement of this depth reconstruction over simpler formulas is demonstrated. Further corrections due to the contribution of hole transport to the signals are discussed.

Fritts, Matthew; Gpfert, Thomas; Wester, Thomas; Zuber, Kai

2012-01-01T23:59:59.000Z

325

Evidence for charge Kondo effect in superconducting Tl-doped PbTe  

SciTech Connect

We report results of low-temperature thermodynamic and transport measurements of Pb{sub 1-x}Tl{sub x}Te single crystals for Tl concentrations up to the solubility limit of approximately x = 1.5%. For all doped samples, we observe a low-temperature resistivity upturn that scales in magnitude with the Tl concentration. The temperature and field dependence of this upturn are consistent with a charge Kondo effect involving degenerate Tl valence states differing by two electrons, with a characteristic Kondo temperature T{sub K} {approx} 6 K. The observation of such an effect supports an electronic pairing mechanism for superconductivity in this material and may account for the anomalously high T{sub c} values.

Fisher, I

2010-01-11T23:59:59.000Z

326

Stabilization of High Efficiency CdTe Photovoltaic Modules in Controlled Indoor Light Soaking  

Science Conference Proceedings (OSTI)

The performance and stabilization of large-area, high-efficiency 9%, CdTe photovoltaic (PV) modules maintained under controlled light-soaking nominally at 800 Watts/m2 irradiance and 65C module temperature are investigated. Degradation of module performance occurs predominantly in the first few hundred hours of exposure under these conditions; these symptoms included losses in fill factor (FF), open-circuit voltage (Voc), and short-circuit current (Isc), which amount to between 7% and 15% total loss in performance. Higher stabilized performance was achieved with lower copper content in the back contact. Transient effects in module Voc and Isc were observed, suggesting partial annealing thereof when stored under low-light levels. Performance changes are analyzed, aided by monitoring the current-voltage characteristics in situ during exposure.

del Cueto, J. A.; Pruett, J.; Cunningham, D.

2003-05-01T23:59:59.000Z

327

Performance of the ATLAS tau trigger with 7 TeV collision data at the LHC  

E-Print Network (OSTI)

Tau leptons are a fundamental ingredient in the discovery of new physics at the LHC. The reconstruction of hadronic tau decays at the trigger level, although a very challenging task in proton-proton collision environments, allows us to double the sample of tau decays collected, and provides additional discovery power to final states which include tau leptons. In this contribution we show the understanding of the tau trigger system using data collected with the ATLAS detector at the LHC in proton-proton collisions at a center-of-mass energy of 7 TeV. We present the most relevant quantities used in the different stages of the trigger selection, and the trigger efficiencies as a function of ET using tau-like QCD events passing the offline reconstruction and identification selection.

Robinson, M; The ATLAS collaboration

2010-01-01T23:59:59.000Z

328

Characterization of detector grade CdZnTe material from Redlen Technologies  

Science Conference Proceedings (OSTI)

CdZnTe (or CZT) crystals can be used in a variety of detector-type applications. This large band gap material shows great promise for use as a gamma radiation spectrometer. Historically, the performance of CZT has typically been adversely affected by point defects, structural and compositional heterogeneities within the crystals, such as twinning, pipes, grain boundaries (polycrystallinity) and secondary phases (SP). The synthesis of CZT material has improved greatly with the primary performance limitation being attributed to mainly SP. In this presentation, we describe the extensive characterization of detector grade material that has been treated with post growth annealing to remove the SPs. Some of the analytical methods used in this study included polarized, cross polarized and transmission IR imaging, I-V curves measurements, synchrotron X-ray topography and electron microscopy.

Duff, Martine C.; Burger, Arnold; Groza, Michael; Buliga, Vladimir; Bradley, John P.; Dai, Zurong R.; Teslich, Nick; Black, David R.; Awadalla, Salah A.; Mackenzie, Jason; Chen, Henry (Redlen); (SRNL); (LLNL); (NIST); (Fisk U)

2008-10-24T23:59:59.000Z

329

Correlations Between Crystal Defects and Performance of CdZnTe Detectors  

Science Conference Proceedings (OSTI)

Poor crystallinity remains a major problem affecting the availability and cost of CdZnTe (CZT) detectors. Point defects are responsible for small gradual charge loss and correlated with the electron clouds' drift times, which allows electronic correction of the output signals to achieve high spectral-resolution even with large-volume CZT detectors. In contrast, extended defects causes significant charge losses, which typically are uncorrelated, and, thus, result in much greater fluctuations of the output signals that cannot be corrected. Although extended defects do not affect all the interaction events, their fraction rapidly increases with the crystal's thickness and volume. In this paper, we summarize our recent results from testing CZT material and detectors that emphasize the particular roles of two types of extended defects, and their contributions to the device's overall performance.

A Bolotnikov; S Babalola; G Camarda; Y Cui; R Gul; S Egarievwe; P Fochuk; M Fuerstnau; J Horace; et al.

2011-12-31T23:59:59.000Z

330

Performance Characteristics of Frisch-Ring CdZnTe Detectors  

Science Conference Proceedings (OSTI)

The performance characteristics of Frisch-ring CdZnTe (CZT) detectors are described and compared with other types of CZT devices. The Frisch-ring detector is a bar-shaped CZT crystal with a geometrical aspect ratio of /spl sim/1:2. The side surfaces of the detector are coated with an insulating layer followed by a metal layer deposited directly upon the insulator. The simple design operates as a single-carrier device. Despite the simplicity of this approach, its performance depends on many factors that are still not fully understood. We describe results of testing several detectors fabricated from CZT material produced by different vendors and compare the results with numerical simulations of these devices.

Bolotnikov,A.; Camarda, G.; Carini, G.; Fiederle, M.; Li, L.; McGregor, D.; McNeil, W.; Wright, G.; James, R.

2006-01-01T23:59:59.000Z

331

Polycrystalline CuInSe{sub 2} and CdTe PV solar cells. Annual subcontract report, 15 April 1993--14 April 1994  

DOE Green Energy (OSTI)

This is an annual technical report on the Phase 2 of a three-year phased research program. The principal objective of the research project is to develop novel and low-cost processes for the fabrication of stable and efficient CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2} and CdTe polycrystalline-thin-film solar cells using reliable techniques amenable to scale-up for economic, large-scale manufacture. The aims are to develop a process for the non-toxic selenization so as to avoid the use of extremely toxic H{sub 2}Se in the fabrication of CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2} thin-film solar cells; to optimize selenization parameters; to develop a process for the fabrication of CdTe solar cells using Cd and Te layers sputtered from elemental targets; to develop an integrated process for promoting the interdiffusion between Cd/Te layers, CdTe phase formation, grain growth, type conversion, and junction formation; to improve adhesion; to minimize residual stresses; to improve the metallic back-contact; to improve the uniformity, stoichiometry, and morphology of CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2} and CdTe thin films; and to improve the efficiency of CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2} and CdTe solar cells.

Dhere, N.G. [Florida Solar Energy Center, Cape Canaveral, FL (United States)

1994-11-01T23:59:59.000Z

332

Polycrystalline CuInSe{sub 2} and CdTe solar cells. Annual subcontract report, April 15, 1992--April 14, 1993  

DOE Green Energy (OSTI)

The principal objective of the research project is to develop processes for the fabrication of cadmium-telluride, CdTe, and copper-indium-gallium-diselenide, Cu(In{sub 1{minus}x}Ga{sub x})Se{sub 2}, polycrystalline-thin-film solar cells using techniques that can be scaled-up for economic manufacture on a large scale. The aims are to fabricate CdTe solar cells using Cd and Te layers sputtered from elemental targets; to promote the interdiffusion between Cd/Te layers, CdTe phase formation, and grain growth; to utilize non-toxic selenization so as to avoid the use of extremely toxic H{sub 2}Se in the fabrication of Cu(In{sub l{minus}x}Ga{sub x})Se{sub 2} thin-film solar cells; to optimize selenization parameters; to improve adhesion; to minimize residual stresses; to improve the uniformity, stoichiometry, and morphology of CdTe and Cu(In{sub 1{minus}x}Ga{sub x})Se{sub 2} thin films, and the efficiency of CdTe and Cu(In{sub 1{minus}x}Ga{sub x})Se{sub 2} solar cells.

Dhere, N.G. [Florida Solar Energy Center, Cape Canaveral, FL (United States)

1994-08-01T23:59:59.000Z

333

Hiding a Heavy Higgs Boson at the 7 TeV LHC  

Science Conference Proceedings (OSTI)

A heavy Standard Model Higgs boson is not only disfavored by electroweak precision observables but is also excluded by direct searches at the 7 TeV LHC for a wide range of masses. Here, we examine scenarios where a heavy Higgs boson can be made consistent with both the indirect constraints and the direct null searches by adding only one new particle beyond the Standard Model. This new particle should be a weak multiplet in order to have additional contributions to the oblique parameters. If it is a color singlet, we find that a heavy Higgs with an intermediate mass of 200-300 GeV can decay into the new states, suppressing the branching ratios for the standard model modes, and thus hiding a heavy Higgs at the LHC. If the new particle is also charged under QCD, the Higgs production cross section from gluon fusion can be reduced significantly due to the new colored particle one-loop contribution. Current collider constraints on the new particles allow for viable parameter space to exist in order to hide a heavy Higgs boson. We categorize the general signatures of these new particles, identify favored regions of their parameter space and point out that discovering or excluding them at the LHC can provide important indirect information for a heavy Higgs. Finally, for a very heavy Higgs boson, beyond the search limit at the 7 TeV LHC, we discuss three additional scenarios where models would be consistent with electroweak precision tests: including an additional vector-like fermion mixing with the top quark, adding another U(1) gauge boson and modifying triple-gauge boson couplings.

Bai, Yang; Fan, JiJi; Hewett, JoAnne L.

2012-03-20T23:59:59.000Z

334

Optical-Fiber-Based, Time-Resolved Photoluminescence Spectrometer for Thin-Film Absorber Characterization and Analysis of TRPL Data for CdS/CdTe Interface: Preprint  

DOE Green Energy (OSTI)

We describe the design of a time resolved photoluminescence (TRPL) spectrometer for rapid semiconductor absorber characterization. Simplicity and flexibility is achieved by using single optical fiber to deliver laser pulses and to collect photoluminescence. We apply TRPL for characterization of CdS/CdTe absorbers after deposition, CdCl2 treatment, Cu doping, and back contact formation. Data suggest this method could be applied in various stages of PV device processing. Finally, we show how to analyze TRPL data for CdS/CdTe absorbers by considering laser light absorption depth and intermixing at CdS/CdTe interface.

Kuciauskas, D.; Duenow, J. N.; Kanevce, A.; Li, J. V.; Young, M. R.; Dippo, P.; Levi, D. H.

2012-06-01T23:59:59.000Z

335

Event activity dependence of Y(nS) production in sqrt(s[NN])=5.02 TeV pPb and sqrt(s)=2.76 TeV pp collisions  

E-Print Network (OSTI)

The production of Y(1S), Y(2S), and Y(3S) is investigated in pPb and pp collisions at centre-of-mass energies per nucleon pair of 5.02 TeV and 2.76 TeV, respectively. The datasets correspond to integrated luminosities of about 31 inverse nanobarns (pPb) and 5.4 inverse picobarns (pp), collected in 2013 by the CMS experiment at the LHC. Upsilons that decay into muons are reconstructed within the rapidity interval abs(y[CM]), are found to rise with both measures of the event activity in pp and pPb. In both collision systems, the ratios of the excited to the ground state cross s...

Chatrchyan, Serguei; CMS Collaboration; Sirunyan, Albert M; Tumasyan, Armen; Adam, Wolfgang; Bergauer, Thomas; Dragicevic, Marko; Er, Janos; Fabjan, Christian; Friedl, Markus; Fruehwirth, Rudolf; Ghete, Vasile Mihai; Hartl, Christian; Hrmann, Natascha; Hrubec, Josef; Jeitler, Manfred; Kiesenhofer, Wolfgang; Knnz, Valentin; Krammer, Manfred; Krtschmer, Ilse; Liko, Dietrich; Mikulec, Ivan; Rabady, Dinyar; Rahbaran, Babak; Rohringer, Herbert; Schfbeck, Robert; Strauss, Josef; Taurok, Anton; Treberer-Treberspurg, Wolfgang; Waltenberger, Wolfgang; Wulz, Claudia-Elisabeth; Mossolov, Vladimir; Shumeiko, Nikolai; Suarez Gonzalez, Juan; Alderweireldt, Sara; Bansal, Monika; Bansal, Sunil; Cornelis, Tom; De Wolf, Eddi A; Janssen, Xavier; Knutsson, Albert; Luyckx, Sten; Mucibello, Luca; Ochesanu, Silvia; Roland, Benoit; Rougny, Romain; Van Haevermaet, Hans; Van Mechelen, Pierre; Van Remortel, Nick; Van Spilbeeck, Alex; Blekman, Freya; Blyweert, Stijn; D'Hondt, Jorgen; Heracleous, Natalie; Kalogeropoulos, Alexis; Keaveney, James; Kim, Tae Jeong; Lowette, Steven; Maes, Michael; Olbrechts, Annik; Strom, Derek; Tavernier, Stefaan; Van Doninck, Walter; Van Mulders, Petra; Van Onsem, Gerrit Patrick; Villella, Ilaria; Caillol, Ccile; Clerbaux, Barbara; De Lentdecker, Gilles; Favart, Laurent; Gay, Arnaud; Hreus, Tomas; Lonard, Alexandre; Marage, Pierre Edouard; Mohammadi, Abdollah; Perni, Luca; Reis, Thomas; Seva, Tomislav; Thomas, Laurent; Vander Velde, Catherine; Vanlaer, Pascal; Wang, Jian; Adler, Volker; Beernaert, Kelly; Benucci, Leonardo; Cimmino, Anna; Costantini, Silvia; Dildick, Sven; Garcia, Guillaume; Klein, Benjamin; Lellouch, Jrmie; Mccartin, Joseph; Ocampo Rios, Alberto Andres; Ryckbosch, Dirk; Sigamani, Michael; Strobbe, Nadja; Thyssen, Filip; Tytgat, Michael; Walsh, Sinead; Yazgan, Efe; Zaganidis, Nicolas; Basegmez, Suzan; Beluffi, Camille; Bruno, Giacomo; Castello, Roberto; Caudron, Adrien; Ceard, Ludivine; Da Silveira, Gustavo Gil; Delaere, Christophe; Du Pree, Tristan; Favart, Denis; Forthomme, Laurent; Giammanco, Andrea; Hollar, Jonathan; Jez, Pavel; Komm, Matthias; Lemaitre, Vincent; Liao, Junhui; Militaru, Otilia; Nuttens, Claude; Pagano, Davide; Pin, Arnaud; Piotrzkowski, Krzysztof; Popov, Andrey; Quertenmont, Loic; Selvaggi, Michele; Vidal Marono, Miguel; Vizan Garcia, Jesus Manuel; Beliy, Nikita; Caebergs, Thierry; Daubie, Evelyne; Hammad, Gregory Habib; Alves, Gilvan; Correa Martins Junior, Marcos; Martins, Thiago; Pol, Maria Elena; Henrique Gomes E Souza, Moacyr; Ald Jnior, Walter Luiz; Carvalho, Wagner; Chinellato, Jose; Custdio, Analu; Da Costa, Eliza Melo; De Jesus Damiao, Dilson; De Oliveira Martins, Carley; Fonseca De Souza, Sandro; Malbouisson, Helena; Malek, Magdalena; Matos Figueiredo, Diego; Mundim, Luiz; Nogima, Helio; Prado Da Silva, Wanda Lucia; Santaolalla, Javier; Santoro, Alberto; Sznajder, Andre; Tonelli Manganote, Edmilson Jos; Vilela Pereira, Antonio; Bernardes, Cesar Augusto; De Almeida Dias, Flavia; Tomei, Thiago; De Moraes Gregores, Eduardo; Lagana, Caio; Mercadante, Pedro G; Novaes, Sergio F; Padula, Sandra; Genchev, Vladimir; Iaydjiev, Plamen; Marinov, Andrey; Piperov, Stefan; Rodozov, Mircho; Sultanov, Georgi; Vutova, Mariana; Dimitrov, Anton; Glushkov, Ivan; Hadjiiska, Roumyana; Kozhuharov, Venelin; Litov, Leander; Pavlov, Borislav; Petkov, Peicho; Bian, Jian-Guo; Chen, Guo-Ming; Chen, He-Sheng; Chen, Mingshui; Du, Ran; Jiang, Chun-Hua; Liang, Dong; Liang, Song; Meng, Xiangwei; Plestina, Roko; Tao, Junquan; Wang, Xianyou; Wang, Zheng; Asawatangtrakuldee, Chayanit; Ban, Yong; Guo, Yifei; Li, Wenbo; Liu, Shuai; Mao, Yajun; Qian, Si-Jin; Teng, Haiyun; Wang, Dayong; Zhang, Linlin; Zou, Wei; Avila, Carlos; Carrillo Montoya, Camilo Andres; Chaparro Sierra, Luisa Fernanda; Florez, Carlos; Gomez, Juan Pablo; Gomez Moreno, Bernardo; Sanabria, Juan Carlos; Godinovic, Nikola; Lelas, Damir; Polic, Dunja; Puljak, Ivica; Antunovic, Zeljko; Kovac, Marko; Brigljevic, Vuko; Kadija, Kreso; Luetic, Jelena; Mekterovic, Darko; Morovic, Srecko; Tikvica, Lucija; Attikis, Alexandros; Mavromanolakis, Georgios; Mousa, Jehad; Nicolaou, Charalambos; Ptochos, Fotios; Razis, Panos A; Finger, Miroslav; Finger Jr, Michael; Abdelalim, Ahmed Ali; Assran, Yasser; Elgammal, Sherif; Ellithi Kamel, Ali; Mahmoud, Mohammed; Radi, Amr; Kadastik, Mario; Mntel, Mait; Murumaa, Marion; Raidal, Martti; Rebane, Liis; Tiko, Andres; Eerola, Paula; Fedi, Giacomo; Voutilainen, Mikko; Hrknen, Jaakko; Karimki, Veikko; Kinnunen, Ritva; Kortelainen, Matti J; Lampn, Tapio; Lassila-Perini, Kati

2013-01-01T23:59:59.000Z

336

X-ray diffraction study of (TlInSe{sub 2}){sub 1-x}(TlGaTe{sub 2}){sub x} crystal system  

Science Conference Proceedings (OSTI)

The crystallographic and dynamic characteristics of TlInSe{sub 2} and TlGaTe{sub 2} crystals have been studied by X-ray diffraction in the temperature range of 85-320 K. The temperature dependences of the unit-cell parameters a of TlInSe{sub 2} and TlGaTe{sub 2} crystals, as well as their coefficients of thermal expansion along the [100] direction, are determined. The concentration dependences of the unit-cell parameters a and c for (TlInSe{sub 2}){sub 1-x}(TlGaTe{sub 2}){sub x} crystals are measured. Anomalies are found in the temperature dependences of the unit-cell parameters a and, correspondingly, the coefficient of thermal expansion, indicating the existence of phase transitions in TlInSe{sub 2} and TlGaTe{sub 2} crystals.

Sheleg, A. U., E-mail: sheleg@ifttp.bas-net.by; Zub, E. M.; Yachkovskii, A. Ya. [National Academy of Sciences of Belarus, State Scientific and Production Association, Scientific and Practical Materials Research Center (Belarus); Mustafaeva, S. N.; Kerimova, E. M. [Azerbaijan National Academy of Sciences, Institute of Physics (Azerbaijan)

2012-03-15T23:59:59.000Z

337

Recrystallization of PVD CdTe Thin Films Induced by CdCl2 Treatment -- A Comparison Between Vapor and Solution Processes: Preprint  

DOE Green Energy (OSTI)

This paper describes the large concentration of 60..deg.. <111> twin boundaries that was observed in every CdTe film analyzed in this work, even after recrystallization and grain growth, confirming the low energy of these interfaces.

Mountinho, H. R.; Dhere, R. G.; Romero, M. J.; Jiang, C. S.; To, B.; Al-Jassim, M. M.

2008-05-01T23:59:59.000Z

338

Influence of Surface Preparation on Scanning Kelvin Probe Microscopy and Electron Backscatter Diffraction Analysis of Cross Sections of CdTe/CdS Solar Cells: Preprint  

DOE Green Energy (OSTI)

In this work we investigated different methods to prepare cross sections of CdTe/CdS solar cells for EBSD and SKPM analyses. We observed that procedures used to prepare surfaces for EBSD are not suitable to prepare cross sections, and we were able to develop a process using polishing and ion-beam milling. This process resulted in very good results and allowed us to reveal important aspects of the cross section of the CdTe film. For SKPM, polishing and a light ion-beam milling resulted in cross sections that provided good data. We were able to observe the depletion region on the CdTe film and the p-n junction as well as the interdiffusion layer between CdTe and CdS. However, preparing good-quality cross sections for SKPM is not a reproducible process, and artifacts are often observed.

Moutinho, H. R.; Dhere, R. G.; Jiang, C. S.; Al-Jassim, M. M.

2011-06-01T23:59:59.000Z

339

Search for the Higgs Boson in the H?WW[superscript (*)]??[superscript +]??[superscript -]?? Decay Channel in pp Collisions at ?s=7??TeV with the ATLAS Detector  

E-Print Network (OSTI)

A search for the Higgs boson has been performed in the H?WW[superscript (*)]??[superscript +]??[superscript -]?? channel (?=e/?) with an integrated luminosity of 2.05??fb[superscript -1] of pp collisions at ?s=7??TeV ...

Taylor, Frank E.

340

Effect of nonstoichiometry on the electrophysical properties of the layered compounds Ge{sub 3}Bi{sub 2}Te{sub 6} and GeBi{sub 2}Te{sub 4}  

Science Conference Proceedings (OSTI)

The objective of this work was to investigate the effect of deviation from stoichiometry on the electrophysical properties (electrical and thermal conductivity, thermoelectric power, and carrier concentration) of the ternary layered semiconducting compounds Ge{sub 3{plus_minus}{delta}1}Bi{sub 2+{delta}2}Te{sub 6+{delta}3} and Ge{sub 1{plus_minus}{delta}3}, which are promising for use in thermoelectric converters.The electrophysical properties were measured at 300 K. The Ge{sub 1-{delta}1}Bi{sub 2+{delta}3} alloys were studied by powder X-ray diffraction analysis on a DRON UM-1 diffractometer (CoK{sub {alpha}} radiation). It was found that Ge{sub 3{plus_minus}{delta}1} Bi{sub 2+{delta}2}Te{sub 6{plus_minus}{delta}3} is a nonstoichiometric phase with p-type conductivity throughout the {delta}{sub 1}, {delta}{sub 2}, and {delta}{sub 3} ranges examined. Our results suggest that cation vacancies are likely to be the dominant nonstoichiometric defects responsible for the high concentration of holes. The conductivity of Ge{sub 1{plus_minus}{delta}1}Bi{sub 2}Te{sub 4} changes from the p-type in the Ge-deficient alloys to the n-type in the Gerich alloys.

Shelimova, L.E.; Karpinskii, O.G.; Avilov, E.S.; Kretova, M.A.; Lubman, C.U. [Baikov Institute of Metallurgy, Moscow (Russian Federation)

1994-12-01T23:59:59.000Z

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341

The improvement of near-term CdTe processing and product capabilities and establishment of next-generation CdTe technology. Annual technical progress report, September 1, 1995--August 31, 1996  

DOE Green Energy (OSTI)

The potential of photovoltaics to become a major global business enterprise still lingers outside the limits of industrial capabilities. For the Cadmium Sulfide/Cadmium Telluride (CdS/CdTe) system this potential has continued to focus on improvements in efficiency, stability, and cost reduction. This triad is the primary objective of the present subcontract with NREL entitled {open_quotes}The Improvement of Near-term CdTe Processing and Product Capabilities & Establishment of Next Generation CdTe Technology{close_quotes}. This subcontract represents an intermediate stage of NREL`s plan to assist the growth of the photovoltaic industry in overcoming the scientific and technical barriers to commercialization. This report outlines the progress that has been made during the period of August 1995 through August 1996. The objectives of this subcontract are to improve processing methods, quantify and understand efficiency improvement mechanisms, meet life-testing goals, and address cadmium safety concerns. Task and subtask goals are defined to meet these objectives in specific areas. The approach to fulfilling the subcontract goals is through a balanced plan of process improvement and mechanism identification. These are carried out and continued through monitoring under various long term and accelerated stress conditions. GPI maintains an on-going awareness of all safety related issues, can in particular, those involving cadmium.

Kester, J.; Albright, S. [Golden Photon, Inc., CO (United States)

1997-07-01T23:59:59.000Z

342

Development of a computer model for polycrystalline thin-film CuInSe sub 2 and CdTe solar cells  

DOE Green Energy (OSTI)

This report describes work to develop a highly accurate numerical model for CuInSe{sub 2} and CdTe solar cells. ADEPT (A Device Emulation Program and Toolbox), a one-dimensional semiconductor device simulation code developed at Purdue University, was used as the basis of this model. An additional objective was to use ADEPT to analyze the performance of existing and proposed CuInSe{sub 2} and CdTe solar cell structures. The work is being performed in two phases. The first phase involved collecting device performance parameters, cell structure information, and material parameters. This information was used to construct the basic models to simulate CuInSe{sub 2} and CdTe solar cells. This report is a tabulation of information gathered during the first phase of this project on the performance of existing CuInSe{sub 2} and CdTe solar cells, the material properties of CuInSr{sub 2}, CdTe, and CdS, and the optical absorption properties of CuInSe{sub 2}, CdTe, and CdS. The second phase will entail further development and the release of a version of ADEPT tailored to CuInSe{sub 2} and CdTe solar cells that can be run on a personal computer. In addition, ADEPT will be used to analyze the performance of existing and proposed CuInSe{sub 2} and CdTe solar cell structures. 110 refs.

Gray, J.L.; Schwartz, R.J.; Lee, Y.J. (Purdue Univ., Lafayette, IN (United States))

1992-04-01T23:59:59.000Z

343

Growth and structure of photosensitive Pb{sub 1-x}Mn{sub x}Te(Ga) epitaxial films  

Science Conference Proceedings (OSTI)

The growth and structure of (1-1.5)-{mu}m-thick Pb{sub 1-x}Mn{sub x}Te(Ga)(x = 0.06) films with 0.4-0.9 at % of gallium, grown on BaF{sub 2}(111) and Pb{sub 1-x}Sn{sub x}Te (x = 0.2) (100) substrates by molecular beam epitaxy, have been investigated. It is established that the films are crystallized into an fcc structure, and their growth planes are (111) and (100), according to the substrate orientation. The optimal conditions for obtaining high-resistivity photosensitive p-and n-type films with a perfect crystal structure (W{sub 1/2} = 80''-100'') have been determined.

Nuriev, I. R.; Sadygov, R. M.; Nazarov, A. M., E-mail: afinnazarov@yahoo.com [Azerbaijan National Academy of Sciences, Institute of Physics (Azerbaijan)

2008-05-15T23:59:59.000Z

344

High-efficiency large-area CdTe panels. Final subcontract report, June 1987--July 1990  

DOE Green Energy (OSTI)

The objective of this three year effort has been to develop an improved materials technology and fabrication process for limited volume production of 1 ft{sup 2} and 4 ft{sup 2} CdS/CdTe photovoltaic modules. The module stability objective by the end of this three year subcontract was to develop techniques to provide ten year life exploration with no greater than 10% degradation. In order to achieve these efficiency and stability objectives, the research program has been separated into tasks including: (1) analysis and characterization of CdS/CdTe Devices; (2) performance optimization on small cells; (3) encapsulation and stability testing; and (4) module efficiency optimization. 27 refs., 18 figs., 3 tabs.

Albright, S.P.; Chamberlin, R.R.; Jordan, J.F. [Photon Energy, Inc., El Paso, TX (USA)

1990-11-01T23:59:59.000Z

345

Investigation of Charge Transport Properties of CdZnTe Detectors with Synchrotron X-ray Radiation  

Science Conference Proceedings (OSTI)

Various internal defects, such as Te inclusions, twin boundaries, dislocation, etc., are prevalent in as-grown CdZnTe (CZT) crystals, which affect the charge transport properties of CZT crystals and, therefore, worsen the performance of CZT detectors. In order to develop high quality CZT detectors, it is imperative to clarify the effects of internal defects on the charge transport properties of CZT. Simple flood illumination with nuclear radiation source cannot reveal the nature of highly localized defects in CZT. Therefore, at Brookhaven's National Synchrotron Light Source (NSLS), we have developed a unique testing system for micro-scale defect investigation of CZT, which employs an X-ray beam collimated with the spatial resolution as small as 3 x 3 {micro}m{sup 2}, a microscopic size comparable to the scale of common defects in CZT. This powerful tool enables us to investigate the effect of internal defects on charge transport properties of CZT in detail.

Yang,G.; Bolotnikov, A.E.; Camarda, G.S.; Cui, Y.; Hossain, A.; James, R.B.

2008-10-19T23:59:59.000Z

346

Molecular beam epitaxy growth of PbSe on Si (211) using a ZnTe buffer layer  

Science Conference Proceedings (OSTI)

The authors report the results of successful growth of single crystalline PbSe on Si (211) substrates with ZnTe as a buffer layer by molecular beam epitaxy. Single crystalline PbSe with (511) orientation was achieved on ZnTe/Si (211), as evidenced by RHEED patterns indicative of 2 dimensional (2D) growth, x ray diffraction rocking curves with a full width at half maximum as low as 153 arc sec and mobility as large as 1.1x10{sup 4}cm{sup 2}V{sup -1}s{sup -1} at 77 K. Cross hatch patterns were found on the PbSe(511) surface in Nomarski filtered microscope images suggesting the presence of a surface thermal strain relaxation mechanism, which was confirmed by Fourier transformed high resolution transmission electron microscope images.

Wang, X. J.; Chang, Y.; Hou, Y. B.; Becker, C. R.; Kodama, R.; Aqariden, F.; Sivananthan, S. [Microphysics Laboratory, Physics Department, University of Illinois at Chicago, Illinois 60607 (United States); Microphysics Laboratory, Physics Department, University of Illinois at Chicago, Illinois 60607 and Physics Department and Quantum Functional Semiconductor Research Center, Dongguk University 3-26, Seoul 100-715 (Korea, Republic of); Microphysics Laboratory, Physics Department, University of Illinois at Chicago, Illinois 60607 (United States); EPIR Technologies, Bolingbrook, Illinois 60440 (United States); Microphysics Laboratory, Physics Department, University of Illinois at Chicago, Illinois 60607 and EPIR Technologies, Bolingbrook, Illinois 60440 (United States)

2011-09-15T23:59:59.000Z

347

The Effect of High-Resistance SnO2 on CdS/CdTe Device Performance  

DOE Green Energy (OSTI)

In this paper, we have studied the effect of high-resistance SnO2 buffer layers, deposited by low-pressure chemical-vapor deposition, on CdS/CdTe device performance. Our results indicate that when CdS/CdTe devices have a very thin layer of CdS or no CdS at all, the i-SnO2 buffer layer helps to increase device efficiency. When the CdS layer is thicker than 600{angstrom}, the device performance is dominated by CdS thickness, not the i-SnO2 layer. If a very thin CdS layer is to be used to enhance device performance, we conclude that a better SnO2 buffer layer is needed.

Li, W.; Ribelin, R.; Mahathongdy, Y.; Albin, D.; Dhere, R.; Rose, D.; Asher, S.; Moutinho, H.; Sheldon, P.

1998-10-06T23:59:59.000Z

348

{gamma}-ray spectroscopy of neutron-deficient {sup 110}Te. II. High-spin smooth-terminating structures  

Science Conference Proceedings (OSTI)

High-spin states have been populated in {sub 52}{sup 110}Te via {sup 58}Ni({sup 58}Ni,{alpha}2p{gamma}) reactions at 240 and 250 MeV. The Gammasphere {gamma}-ray spectrometer was used in conjunction with the Microball charged-particle detector. The high-spin (I>30) collective level scheme of {sup 110}Te, up to {approx}45({Dirac_h}/2{pi}), is discussed in this paper. Four new decoupled ({delta}I=2) high-spin structures have been observed for the first time, together with two strongly coupled ({delta}I=1) bands. These bands all show the characteristics of smooth band termination, and are discussed within the framework of the cranked Nilsson-Strutinsky approach.

Paul, E. S.; Evans, A. O.; Boston, A. J.; Nolan, P. J.; Semple, A. T. [Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 7ZE (United Kingdom); Chiara, C. J.; Fossan, D. B.; Lane, G. J.; Sears, J. M.; Starosta, K. [Department of Physics and Astronomy, State University of New York at Stony Brook, Stony Brook, New York 11794-3800 (United States); Devlin, M.; LaFosse, D. R.; Sarantites, D. G. [Department of Chemistry, Washington University, St. Louis, Missouri 63130 (United States); Freeman, S. J.; Leddy, M. J. [Schuster Laboratory, The University of Manchester, Brunswick Street, Manchester M13 9PL (United Kingdom); Lee, I. Y.; Macchiavelli, A. O. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Smith, J. F. [Department of Physics and Astronomy, State University of New York at Stony Brook, Stony Brook, New York 11794-3800 (United States); Schuster Laboratory, The University of Manchester, Brunswick Street, Manchester M13 9PL (United Kingdom); Afanasjev, A. V. [Department of Physics and Astronomy, Mississippi State University, Mississippi 39762 (United States); Department of Mathematical Physics, Lund Institute of Technology, P. O. Box 118, S-22100 Lund (Sweden); Laboratory of Radiation Physics, Institute of Solid State Physics, University of Latvia, LV 2169 Salaspils, Miera str. 31 (Latvia); Ragnarsson, I. [Department of Mathematical Physics, Lund Institute of Technology, P. O. Box 118, S-22100 Lund (Sweden)

2007-09-15T23:59:59.000Z

349

A search for GeV-TeV emission from Gamma-ray Bursts using the Milagro detector  

E-Print Network (OSTI)

A search for GeV-TeV emission from Gamma-ray Bursts using the Milagro detector p. M. Saz Parkinson of operation. Keywords: gamma-ray sources; gamma-ray bursts; astronomical observations gamma-ray; gamma-ray telescope; Milagro PACS: 95.55.Ka; 95.85.Pw; 98.70.Rz INTRODUCTION Gamma-ray bursts (GRBs) were detected up

California at Santa Cruz, University of

350

Appendix B: CArBon dioxide CApture teChnology SheetS R&D CollaboRation...  

NLE Websites -- All DOE Office Websites (Extended Search)

R&D CollaboRations B-556 R&D CollaboRations U.s. DepaRtment of eneRgy aDvanCeD CaRbon DioxiDe CaptURe R&D pRogRam: teChnology UpDate, may 2013 paRtneRship foR Co 2 CaptURe primary...

351

On the Origin of TeV Gamma-ray Emission from HESS J1834-087  

E-Print Network (OSTI)

We present an X-ray study of the field containing the extended TeV source HESS J1834-087 using data obtained with the XMM-Newton telescope. Previously, the coincidence of this source with both the shell-type supernova remnant (SNR) W41 and a giant molecular cloud (GMC) was interpreted as favoring pi^0-decay gamma-rays from interaction of the old SNR with the GMC. Alternatively, the TeV emission has been attributed to inverse Compton scattering from leptons deposited by PSR J1833-0827, a pulsar assumed to have been born in W41 but now located 24' from the center of the SNR (and the TeV source). Instead, we argue for a third possibility, that the TeV emission is powered by a previously unknown pulsar wind nebula located near the center of W41. The candidate pulsar is XMMU J183435.3-084443, a hard X-ray point source that lacks an optical counterpart to R>21 and is coincident with diffuse X-ray emission. The X-rays from both the point source and diffuse feature are evidently non-thermal and highly absorbed. A best fit power-law model yields photon index Gamma ~ 0.2 and Gamma ~ 1.9, for the point source and diffuse emission, respectively, and 2-10 keV flux ~ 5 X 10^(-13) ergs/cm^(2)/s for each. At the measured 4 kpc distance of W41, the observed X-ray luminosity implies an energetic pulsar with Edot ~ 10^(36)d_4^2 ergs/s, which is also sufficient to generate the observed gamma-ray luminosity of 2.7 X 10^(34)d_4^2 ergs/s via inverse Compton scattering.

R. Mukherjee; E. V. Gotthelf; J. P. Halpern

2008-10-09T23:59:59.000Z

352

The effects of the band bending caused by interface states in CdTe and CIS solar cells  

DOE Green Energy (OSTI)

In this paper, the effects of interface states in the Z-nO/CdS/CuinSe{sub 2}, and CdS/CdTe solar cells are presented. The effects are investigated through numerical modeling using ADEPT (A Device Emulation Program and Tool). The results show that donor-like interface states have very little effect but acceptor-like interface states at the resistive ZnO/CdS can cause pinning of the bands at the interface, thus leading to non-exponential illuminated I-V curves when the interface state densities are high enough. High density of acceptor-like states between the CdS and In-rich CIS does not result in the two-diode like IV curves. Instead they can significantly lower the fill factor. In the CdS/CdTe solar cells. either donor- or acceptor-like interface states have little effect since almost all the depletion region lies in the CdTe. Thus, the metallurgical junction where the interface states are located is away from the electrical junction where the conductivity type changes.

Lee, Youn-Jung; Gray, J.L. [Purdue Univ., Lafayette, IN (United States). School of Electrical Engineering

1994-12-31T23:59:59.000Z

353

Deep radio images of the HEGRA and Whipple TeV sources in the Cygnus OB2 region  

E-Print Network (OSTI)

Context. The modern generation of Cherenkov telescopes has revealed a new population of gamma-ray sources in the Galaxy. Some of them have been identified with previously known X-ray binary systems while other remain without clear counterparts a lower energies. Our initial goal here was reporting on extensive radio observations of the first extended and yet unidentified source, namely TeV J2032+4130. This object was originally detected by the HEGRA telescope in the direction of the Cygnus OB2 region and its nature has been a matter of debate during the latest years. Aims. We aim to pursue our radio exploration of the TeV J2032+4130 position that we initiated in a previous paper but taking now into account the latest results from new Whipple and MILAGRO TeV telescopes. Methods. Our investigation is mostly based on interferometric radio observations with the Giant Metre Wave Radio Telescope (GMRT) close to Pune (India) and the Very Large Array (VLA) in New Mexico (USA). We also conducted near infrared observati...

Marti, Josep; Ishwara Chandra C H; Bosch-Ramon, Valenti

2007-01-01T23:59:59.000Z

354

Interplay between Superconductivity and Magnetism in Fe1-xPdxTe  

Science Conference Proceedings (OSTI)

The love/hate relationship between superconductivity and magnetic ordering has fascinated the condensed matter physics community for a century. In the early days, magnetic impurities doped into a superconductor were found to quickly suppress superconductivity. Later, a variety of systems, such as cuprates, heavy fermions and Fe pnictides, show superconductivity in a narrow region near the border to antiferromagnetism (AFM) as a function of pressure or doping. On the other hand, the coexistence of superconductivity and ferromagnetic (FM) or AFM ordering is found in a few compounds (RRh4B4 (R = Nd, Sm, Tm, Er), R'Mo6X8 (R' = Tb, Dy, Er, Ho, and X = S, Se), UMGe (M = Ge, Rh, Co), CeCoIn5, EuFe2(As1-xPx)2 etc.), providing evidence for their compatibility. Here, we present a third situation, where superconductivity coexists with FM and near the border of AFM in Fe1-xPdxTe. The doping of Pd for Fe gradually suppresses the first-order AFM ordering at temperature TN/S, and turns into short-range (SR) AFM correlation with a characteristic peak in magnetic susceptibility at T'N. Superconductivity sets in when T'N reaches zero. However, there is a gigantic ferromagnetic dome imposed in the superconducting-AFM (SR) crossover regime. Such a system is ideal for studying the interplay between superconductivity and two types of magnetic interactions (FM and AFM).

Karki, A B [Louisiana State University; Garlea, Vasile O [ORNL; Custelcean, Radu [ORNL; Stadler, S. [Louisiana State University; Plummer, E. W. [Louisiana State University; Jin, Rongying [Louisiana State University

2013-01-01T23:59:59.000Z

355

Photohadronic Origin of the TeV-PeV Neutrinos Observed in IceCube  

E-Print Network (OSTI)

We perform an unbiased search of the origin of the recently observed 28 events above ~30 TeV in the IceCube neutrino observatory, assuming that these are (apart from the atmospheric background) of astrophysical origin produced by photohadronic interactions. Instead of relying on the normalization of the neutrino flux, we demonstrate that spectral shape and flavor composition can be used to constrain or identify the source class. In order to quantify our observations, we use a model where the target photons are produced by the synchrotron emission of co-accelerated electrons, and we include magnetic field effects on the secondary muons, pions, and kaons. We find that the lack of observed events with energies much larger than PeV points towards sources with strong magnetic fields, which do not exhibit a direct correlation between highest cosmic ray and neutrino energies. While the simplest AGN models with efficient proton acceleration plausibly describe the current data at about the 3sigma confidence level, we show that IceCube can rule out that the observed neutrinos stem from the sources of the ultra-high energy cosmic rays with a factor of ten increased statistics at more than 5sigma if the current observations are confirmed. A possible caveat are sources with strong magnetic fields and high Lorentz factors, such as magnetic energy dominated GRBs.

Walter Winter

2013-07-10T23:59:59.000Z

356

NNLO Benchmarks for Gauge and Higgs Boson Production at TeV Hadron Colliders  

E-Print Network (OSTI)

The inclusive production cross sections for $W^+, W^-$ and $Z^0$-bosons form important benchmarks for the physics at hadron colliders. We perform a detailed comparison of the predictions for these standard candles based on recent next-to-next-to-leading order (NNLO) parton parameterizations and new analyses including the combined HERA data, compare to all available experimental results, and discuss the predictions for present and upcoming RHIC, SPS, Tevatron and LHC energies. The rates for gauge boson production at the LHC can be rather confidently predicted with an accuracy of better than about 10% at NNLO. We also present detailed NNLO predictions for the Higgs boson production cross sections for Tevatron and LHC energies (1.96, 7, 8, 14 TeV), and propose a possible method to monitor the gluon distribution experimentally in the kinematic region close to the mass range expected for the Higgs boson. The production cross sections of the Higgs boson at the LHC are presently predicted with an accuracy of about 10--17%. The inclusion of the NNLO contributions is mandatory for achieving such accuracies since the total uncertainties are substantially larger at NLO.

S. Alekhin; J. Blmlein; P. Jimenez-Delgado; S. Moch; E. Reya

2010-11-29T23:59:59.000Z

357

Effects of Bulk and Surface Conductivity on the Performance of CdZnTe Pixel Detectors  

E-Print Network (OSTI)

We studied the effects of bulk and surface conductivity on the performance of high-resistivity CdZnTe (CZT) pixel detectors with Pt contacts. We emphasize the difference in mechanisms of the bulk and surface conductivity as indicated by their different temperature behaviors. In addition, the existence of a thin (10-100 A) oxide layer on the surface of CZT, formed during the fabrication process, affects both bulk and surface leakage currents. We demonstrate that the measured I-V dependencies of bulk current can be explained by considering the CZT detector as a metal-semiconductor-metal system with two back-to-back Schottky-barrier contacts. The high surface leakage current is apparently due to the presence of a low-resistivity surface layer that has characteristics which differ considerably from those of the bulk material. This surface layer has a profound effect on the charge collection efficiency in detectors with multi-contact geometry; some fraction of the electric field lines originated on the cathode int...

Bolotnikov, A E; Cook, W R; Harrison, F A; Kuvvetli, I; Schindler, S; Bolotnikov, Aleksey E.; Cook, Walter R.; Harrison, Fiona A.; Kuvvetli, Irfan; Schindler, Stephen M.

2001-01-01T23:59:59.000Z

358

Performance of the ATLAS Calorimeter Trigger with 7 TeV collision data  

E-Print Network (OSTI)

Since the start of the LHC physics programme earlier this year, the ATLAS detector has been collecting proton-proton collisions at a 7 TeV center of mass Energy. As the LHC luminosity rises the ATLAS trigger system must become increasingly selective to reduce the event rate from a design bunch crossing rate of 40 MHz to about 200 Hz for recording. To achieve this the trigger algorithms must meet challenging requirements in terms of speed and selectivity. The trigger is hardware based at level-1 and uses software algorithms running on a farm of commercial processors at the two higher trigger levels. The calorimeter-based software algorithms have been designed with a common part optimized for fast access to detector data and subsequent stages tailored for maximum selectivity for specific signatures such as electrons, photons, jets, taus and missing total energy. We present the physics performance achieved during 2010 data taking, highlighting the key performance aspects for the different signatures. Event featu...

Damazio, Denis; The ATLAS collaboration

2010-01-01T23:59:59.000Z

359

Measurement of b hadron production fractions in 7 TeV pp collisions  

E-Print Network (OSTI)

Measurements of $b$ hadron production ratios in proton-proton collisions at a centre-of-mass energy of 7 TeV with an integrated luminosity of 3 pb$^{-1}$ are presented. We study the ratios of strange $B$ meson to light $B$ meson production $f_s/(f_u+f_d)$ and $\\Lambda_b^0$ baryon to light $B$ meson production $f_{\\Lambda_b}/(f_u+f_d)$ as a function of the charmed hadron-muon pair transverse momentum $p_T$ and the $b$ hadron pseudorapidity $\\eta$, for $p_T$ between 0 and 14 GeV and $\\eta$ between 2 and 5. We find that $f_s/(f_u+f_d)$ is consistent with being independent of $p_{\\rm T}$ and $\\eta$, and we determine $f_s/(f_u+f_d)$ = 0.134$\\pm$ 0.004 $^{+0.011}_{-0.010}$, where the first error is statistical and the second systematic. The corresponding ratio $f_{\\Lambda_b}/(f_u+f_d)$ is found to be dependent upon the transverse momentum of the charmed hadron-muon pair, $f_{\\Lambda_b}/(f_u+f_d)=(0.404\\pm 0.017 (stat) \\pm 0.027 (syst) \\pm 0.105 (Br))$ $\\times$ $[1 -(0.031 \\pm 0.004 (stat) \\pm 0.003 (syst))\\times p_...

Aaij, R; Adeva, B; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amhis, Y; Anderson, J; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Arrabito, L; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Bailey, D S; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bates, A; Bauer, C; Bauer, Th; Bay, A; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Benayoun, M; Bencivenni, G; Benson, S; Benton, J; Bernet, R; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bizzeti, A; Bjrnstad, P M; Blake, T; Blanc, F; Blanks, C; Blouw, J; Blusk, S; Bobrov, A; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Brisbane, S; Britsch, M; Britton, T; Brook, N H; Brown, H; Bchler-Germann, A; Burducea, I; Bursche, A; Buytaert, J; Cadeddu, S; Caicedo Carvajal, J M; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carson, L; Carvalho Akiba, K; Casse, G; Cattaneo, M; Charles, M; Charpentier, Ph; Chiapolini, N; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Collins, P; Comerma-Montells, A; Constantin, F; Conti, G; Contu, A; Cook, A; Coombes, M; Corti, G; Cowan, G A; Currie, R; D'Almagne, B; D'Ambrosio, C; David, P; De Bonis, I; De Capua, S; De Cian, M; De Lorenzi, F; De Miranda, J M; De Paula, L; De Simone, P; Decamp, D; Deckenhoff, M; Degaudenzi, H; Deissenroth, M; Del Buono, L; Deplano, C; Derkach, D; Deschamps, O; Dettori, F; Dickens, J; Dijkstra, H; Diniz Batista, P; Domingo Bonal, F; Donleavy, S; Dordei, F; Dosil Surez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Dziurda, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisele, F; Eisenhardt, S; Ekelhof, R; Eklund, L; Elsasser, Ch; Elsby, D; Esperante Pereira, D; Estve, L; Falabella, A; Fanchini, E; Frber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Fernandez Albor, V; Ferro-Luzzi, M; Filippov, S; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Frank, M; Frei, C; Frosini, M; Furcas, S; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garnier, J-C; Garofoli, J; Garra Tico, J; Garrido, L; Gascon, D; Gaspar, C; Gauvin, N; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Gligorov, V V; Gbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gndara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugs, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Haefeli, G; Haen, C; Haines, S C; Hampson, T; Hansmann-Menzemer, S; Harji, R; Harnew, N; Harrison, J; Harrison, P F; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicks, E; Holubyev, K; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Huston, R S; Hutchcroft, D; Hynds, D; Iakovenko, V; Ilten, P; Imong, J; Jacobsson, R; Jaeger, A; Jahjah Hussein, M; Jans, E; Jansen, F; Jaton, P; Jean-Marie, B; Jing, F; John, M; Johnson, D; Jones, C R; Jost, B; Kaballo, M; Kandybei, S; Karacson, M; Karbach, T M; Keaveney, J; Kenyon, I R; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kim, Y M; Knecht, M; Koppenburg, P; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kruzelecki, K; Kucharczyk, M; Kumar, R; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Le Gac, R; van Leerdam, J; Lees, J-P; Lefvre, R; Leflat, A; Lefranois, J; Leroy, O; Lesiak, T; Li, L; Li Gioi, L; Lieng, M; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Luisier, J; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Magnin, J; Malde, S; Mamunur, R M D; Manca, G; Mancinelli, G; Mangiafave, N; Marconi, U; Mrki, R; Marks, J; Martellotti, G; Martens, A; Martin, L; Martn Snchez, A; Martinez Santos, D; Massafferri, A; Mathe, Z; Matteuzzi, C; Matveev, M; Maurice, E; Maynard, B; Mazurov, A; McGregor, G; McNulty, R; Mclean, C; Meissner, M; Merk, M; Merkel, J; Messi, R; Miglioranzi, S; Milanes, D A; Minard, M-N; Monteil, S; Moran, D; Morawski, P; Mountain, R; Mous, I; Muheim, F; Mller, K; Muresan, R; Muryn, B; Musy, M; Mylroie-Smith, J; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I; Nedos, M; Needham, M; Neufeld, N; Nguyen-Mau, C; Nicol, M; Nies, S; Niess, V; Nikitin, N; Nomerotski, A; Novoselov, A; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Pal, K; Palacios, J; Palano, A; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G

2012-01-01T23:59:59.000Z

360

Optimization of a parallel hole collimator/CdZnTe gamma-camera architecture for scintimammography  

Science Conference Proceedings (OSTI)

Purpose: Small field-of-view CdZnTe (CZT) gamma cameras are increasingly studied for breast lesion detection to complement mammography or ultrasonographic findings. However, in classical collimation configurations, they remain limited by the trade-off between spatial resolution and sensitivity. The HiSens architecture was proposed to overcome these limitations. Using an accurate 3D localization of the interactions inside the detector, this architecture leads to a gain in sensitivity without loss in spatial resolution. In this article, the relevance of the HiSens architecture for planar scintimammography is studied. Methods: A detective quantum efficiency (DQE) computation method is developed and used to optimize the dimensioning of a parallel hole collimator dedicated to scintimammography. Based on the DQE curves, the impact of the collimator-to-detector distance is studied. Two algorithms are proposed to combine data acquired with different collimator-to-detector distances. Results: It is shown that CZT detector virtual pixelization increases system sensitivity by 3.3 while preserving a standard LEHR spatial resolution. The introduction of a gap between the CZT detector and the collimator is useful to modulate the DQE curve shape. The combination of data acquired using different gaps in the image formation process leads to enhanced restoration of the frequency content of the images, resulting in image contrast and spatial resolution improvements. Conclusions: Acquisition duration or injected activity could be markedly reduced if the HiSens architecture with an appropriate collimator-detector gap were used.

Robert, Charlotte; Montemont, Guillaume; Rebuffel, Veronique; Verger, Loieck; Buvat, Irene [CEA-LETI-MINATEC, F38054 Grenoble (France); IMNC-UMR 8165 CNRS, Universites Paris 7 et 11, Batiment 440, 91406 Orsay (France)

2011-04-15T23:59:59.000Z

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361

X-ray Topography to Characterize Surface Damage on CdZnTe Crystals  

Science Conference Proceedings (OSTI)

Synthetic CdZnTe or 'CZT' crystals can be used for room temperature detection of {gamma}-radiation. Structural/morphological heterogeneities within CZT, such as twinning, secondary phases (often referred to as inclusions or precipitates), and poly-crystallinity can affect detector performance. As part of a broader study using synchrotron radiation techniques to correlate detector performance to microstructure, x-ray topography (XRT) has been used to characterize CZT crystals. We have found that CZT crystals almost always have a variety of residual surface damage, which interferes with our ability to observe the underlying microstructure for purposes of crystal quality evaluation. Specific structures are identifiable as resulting from fabrication processes and from handling and shipping of sample crystals. Etching was found to remove this damage; however, our studies have shown that the radiation detector performance of the etched surfaces was inferior to the as-polished surface due to higher surface currents which result in more peak tailing and less energy resolution. We have not fully investigated the effects of the various types of inducible damage on radiation detector performance. (authors)

Black, David; Woicik, Joseph [NIST, Gaithersburg, Maryland (United States); Duff, Martine C.; Hunter, Douglas B. [SRNL, Aiken, South Carolina (United States); Burger, Arnold; Groza, Michael [Fisk University, Nashville, Tennessee (United States)

2008-07-01T23:59:59.000Z

362

X-ray Topography to Characterize Surface Damage on CdZnTe Crystals  

Science Conference Proceedings (OSTI)

Synthetic CdZnTe or 'CZT' crystals can be used for room temperature detection of {gamma}-radiation. Structural/morphological heterogeneities within CZT, such as twinning, secondary phases (often referred to as inclusions or precipitates), and poly-crystallinity can affect detector performance. As part of a broader study using synchrotron radiation techniques to correlate detector performance to microstructure, x-ray topography (XRT) has been used to characterize CZT crystals. We have found that CZT crystals almost always have a variety of residual surface damage, which interferes with our ability to observe the underlying microstructure for purposes of crystal quality evaluation. Specific structures are identifiable as resulting from fabrication processes and from handling and shipping of sample crystals. Etching was found to remove this damage; however, our studies have shown that the radiation detector performance of the etched surfaces was inferior to the as-polished surface due to higher surface currents which result in more peak tailing and less energy resolution. We have not fully investigated the effects of the various types of inducible damage on radiation detector performance.

Black, David; Woicik, Joseph; Duff, Martine C.; Hunter, Douglas B.; Burger, Arnold; Groza, Michael (SRNL); (SBU); (NIST); (Fisk U)

2008-12-05T23:59:59.000Z

363

Smooth terminating bands in {sup 112}Te: Particle-hole induced collectivity  

SciTech Connect

The Gammasphere spectrometer, in conjunction with the Microball charged-particle array, was used to investigate high-spin states in {sup 112}Te via {sup 58}Ni({sup 58}Ni, 4p{gamma}) reactions at 240 and 250 MeV. Several smooth terminating bands were established, and lifetime measurements were performed for the strongest one using the Doppler-shift attenuation method. Results obtained in the spin range 18-32({Dirac_h}/2{pi}) yield a transition quadrupole moment of 4.0{+-}0.5eb, which corresponds to a quadrupole deformation epsilon{sub 2}=0.26{+-}0.03; this value is significantly larger than the ground-state deformation of tellurium isotopes. It was also possible to extract a transition quadrupole moment for the yrast band in {sup 114}Xe, produced via the 58Ni (58Ni, 2p{gamma}) reaction. A value of 3.0{+-}0.5eb was found in the spin range 16-24({Dirac_h}/2{pi}), which corresponds to a quadrupole deformation epsilon{sub 2}=0.19{+-}0.03. Cranked Nilsson-Strutinsky calculations are used to interpret the results.

Paul, E. S.; Evans, A. O.; Boston, A. J.; Chantler, H. J.; Nolan, P. J.; Semple, A. T. [Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 7ZE (United Kingdom); Starosta, K.; Chiara, C. J.; Fossan, D. B.; Lane, G. J.; Sears, J. M.; Vaman, C. [Department of Physics and Astronomy, State University of New York at Stony Brook, Stony Brook, New York 11794-3800 (United States); Devlin, M.; LaFosse, D. R.; Sarantites, D. G. [Department of Chemistry, Washington University, St. Louis, Missouri 63130 (United States); Fletcher, A. M. [Schuster Laboratory, The University of Manchester, Brunswick Street, Manchester M13 9PL (United Kingdom); Lee, I. Y.; Macchiavelli, A. O. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Smith, J. F. [Department of Physics and Astronomy, State University of New York at Stony Brook, Stony Brook, New York 11794-3800, USA (United States); Schuster Laboratory, The University of Manchester, Brunswick Street, Manchester M13 9PL (United Kingdom); Afanasjev, A. V. [Department of Physics and Astronomy, Mississippi State University, Mississippi 39762, USA (United States); Department of Mathematical Physics, Lund Institute of Technology, P.O. Box 118, S-22100 Lund (Sweden); Laboratory of Radiation Physics, Institute of Solid State Physics, University of Latvia, LV 2169 Salaspils, Miera str. 31 (Latvia)] (and others)

2007-01-15T23:59:59.000Z

364

THE COSMOLOGICAL IMPACT OF LUMINOUS TeV BLAZARS. II. REWRITING THE THERMAL HISTORY OF THE INTERGALACTIC MEDIUM  

Science Conference Proceedings (OSTI)

The universe is opaque to extragalactic very high energy gamma rays (VHEGRs, E > 100 GeV) because they annihilate and pair produce on the extragalactic background light. The resulting ultrarelativistic pairs are commonly assumed to lose energy primarily through inverse Compton scattering of cosmic microwave background (CMB) photons, reprocessing the original emission from TeV to GeV energies. In Broderick et al., we argued that this is not the case; powerful plasma instabilities driven by the highly anisotropic nature of the ultrarelativistic pair distribution provide a plausible way to dissipate the kinetic energy of the TeV-generated pairs locally, heating the intergalactic medium (IGM). Here, we explore the effect of this heating on the thermal history of the IGM. We collate the observed extragalactic VHEGR sources to determine a local VHEGR heating rate. Given the pointed nature of VHEGR observations, we estimate the correction for the various selection effects using Fermi observations of high- and intermediate-peaked BL Lac objects. As the extragalactic component of the local VHEGR flux is dominated by TeV blazars, we then estimate the evolution of the TeV blazar luminosity density by tying it to the well-observed quasar luminosity density and producing a VHEGR heating rate as a function of redshift. This heating is relatively homogeneous for z {approx}history of the IGM. Due to the homogeneous nature of the extragalactic background light, TeV blazars produce a uniform volumetric heating rate. This heating is sufficient to increase the temperature of the mean density IGM by nearly an order of magnitude, and at low densities by substantially more. It also naturally produces the inverted temperature-density relation inferred by recent observations of the high-redshift Ly{alpha} forest, a feature that is difficult to reconcile with standard reionization models. Finally, we close with a discussion on the possibility of detecting this hot low-density IGM suggested by our model either directly or indirectly via the local Ly{alpha} forest, the Comptonized CMB, or free-free emission, but we find that such measurements are currently not feasible.

Chang, Philip; Broderick, Avery E.; Pfrommer, Christoph, E-mail: aeb@cita.utoronto.ca, E-mail: pchang@cita.utoronto.ca, E-mail: christoph.pfrommer@h-its.org [Canadian Institute for Theoretical Astrophysics, 60 St. George Street, Toronto, ON M5S 3H8 (Canada)

2012-06-10T23:59:59.000Z

365

The Present, Mid-Term, and Long-Term Supply Curves for Tellurium; and Updates in the Results from NREL's CdTe PV Module Manufacturing Cost Model (Presentation)  

DOE Green Energy (OSTI)

For those PV technologies that rely upon Te, In, and Ga, first-order observations and calculations hint that there may be resource constraints that could inhibit their successful deployment at a SunShot level. These are only first-order approximations, however, and the possibility for an expansion in global Te, In, and Ga supplies needs to be considered in the event that there are upward revisions in their demand and prices.In this study, we examine the current, mid-term, and long-term prospects of Tellurium (Te) for use in PV. We find that the current global supply base of Te would support <10 GW of annual traditional CdTe PV manufacturing production. But as for the possibility that the supply base for Te might be expanded, after compiling several preliminary cumulative availability curves we find that there may be significant upside potential in the supply base for this element - principally vis a vis increasing demand and higher prices. Primarily by reducing the Tellurium intensity in manufacturing and by increasing the recovery efficiency of Te in Cu refining processes, we calculate that it may prove affordable to PV manufacturers to expand the supply base for Te such that 100 GW, or greater, of annual CdTe PV production is possible in the 2030 - 2050 timeframe.

Woodhouse, M.; Goodrich, A.; Redlinger, M.; Lokanc, M.; Eggert, R.

2013-09-01T23:59:59.000Z

366

Development of a computer model for polycrystalline thin-film CuInSe sub 2 and CdTe solar cells  

DOE Green Energy (OSTI)

This report describes work to develop an accurate numerical model for CuInSe{sub 2} (CIS) and CdTe-based solar cells capable of running on a personal computer. Such a model will aid researchers in designing and analyzing CIS- and CdTe-based solar cells. ADEPT (A Device Emulation Pregrain and Tool) was used as the basis for this model. An additional objective of this research was to use the models developed to analyze the performance of existing and proposed CIS- and CdTe-based solar cells. The development of accurate numerical models for CIS- and CdTe-based solar cells required the compilation of cell performance data (for use in model verification) and the compilation of measurements of material parameters. The development of the numerical models involved implementing the various physical models appropriate to CIS and CdTe, as well as some common window. A version of the model capable of running on an IBM-comparable personal computer was developed (primary code development is on a SUN workstation). A user-friendly interface with pop-up menus is continuing to be developed for release with the IBM-compatible model.

Gray, J.L.; Schwartz, R.J.; Lee, Y.J. (Purdue Univ., Lafayette, IN (United States))

1992-09-01T23:59:59.000Z

367

Crystal structure, electronic structure and physical properties of the new low-valent thallium silicon telluride Tl{sub 6}Si{sub 2}Te{sub 6} in comparison to Tl{sub 6}Ge{sub 2}Te{sub 6}  

SciTech Connect

The title compounds were prepared from the elements in the stoichiometric ratio at 800deg. C under exclusion of air. Tl{sub 6}Si{sub 2}Te{sub 6} crystallizes in the space group P1-bar , isostructural with Tl{sub 6}Ge{sub 2}Te{sub 6}, with a=9.4235(6)A, b=9.6606(7)A, c=10.3889(7)A, {alpha}=89.158(2){sup o}, {beta}=96.544(2){sup o}, {gamma}=100.685(2){sup o}, V=923.3(1)A{sup 3} (Z=2). Its structure is composed of dimeric [Si{sub 2}Te{sub 6}]{sup 6-} units with a Si-Si single bond, while the Tl atoms are irregularly coordinated by five to six Te atoms. Numerous weakly bonding Tl-Tl contacts exist. Both title compounds are black semiconductors with small band gaps, calculated to be 0.9eV for Tl{sub 6}Si{sub 2}Te{sub 6} and 0.5eV for Tl{sub 6}Ge{sub 2}Te{sub 6}. The Seebeck coefficients are +65{mu}VK{sup -1} in case of Tl{sub 6}Si{sub 2}Te{sub 6} and +150{mu}VK{sup -1} in case of Tl{sub 6}Ge{sub 2}Te{sub 6} at 300K, and the electrical conductivities are 5.5 and 3{omega}{sup -1}cm{sup -1}, respectively.

Assoud, Abdeljalil [Department of Chemistry, University of Waterloo, Waterloo, Ont., N2L 3G1 (Canada); Soheilnia, Navid [Department of Chemistry, University of Waterloo, Waterloo, Ont., N2L 3G1 (Canada); Kleinke, Holger [Department of Chemistry, University of Waterloo, Waterloo, Ont., N2L 3G1 (Canada)]. E-mail: kleinke@uwaterloo.ca

2006-08-15T23:59:59.000Z

368

High-Efficiency CdTe and CIGS Thin-Film Solar Cells: Highlights and Challenges; Preprint  

DOE Green Energy (OSTI)

Thin-film photovoltaic (PV) modules of CdTe and Cu(In,Ga)Se2 (CIGS) have the potential to reach cost-effective PV-generated electricity. These technologies have transitioned from the laboratory to the market place. Pilot production and first-time manufacturing are ramping up to higher capacity and enjoying a flood of venture-capital funding. CIGS solar cells and modules have achieved 19.5% and 13% efficiencies, respectively. Likewise, CdTe cells and modules have reached 16.5% and 10.2% efficiencies, respectively. Even higher efficiencies from the laboratory and from the manufacturing line are only a matter of time. Manufacturing-line yield continues to improve and is surpassing 85%. Long-term stability has been demonstrated for both technologies; however, some failures in the field have also been observed, emphasizing the critical need for understanding degradation mechanisms and packaging options. The long-term potential of the two technologies require R&D emphasis on science and engineering-based challenges to find solutions to achieve targeted cost-effective module performance, and in-field durability. Some of the challenges are common to both, e.g., in-situ process control and diagnostics, thinner absorber, understanding degradation mechanisms, protection from water vapor, and innovation in high-speed processing and module design. Other topics are specific to the technology, such as lower-cost and fast-deposition processes for CIGS, and improved back contact and voltage for CdTe devices.

Noufi, R.; Zweibel, K.

2006-05-01T23:59:59.000Z

369

N-type thermoelectric recycled carbon fibre sheet with electrochemically deposited Bi{sub 2}Te{sub 3}  

SciTech Connect

An N-type thermoelectric recycled carbon fibre sheet with bismuth telluride coating has been successfully synthesised through an electro-deposition technique. The Seebeck coefficient and electrical properties of the combined recycled carbon fibre sheet and bismuth telluride films are reported. Classification of the crystal structure, surface morphology and the elemental composition of the resulting deposits are methodically characterised by XRD, SEM and EDX. Cyclic voltammetry is also carried out in nitric acid solutions to investigate the right range of deposition potential. The synthesis N-type thermoelectric sheet has a highest attainable Seebeck coefficient of -54 {mu}V K{sup -1} and an electrical resistivity of 8.9 Multiplication-Sign 10{sup -5} Ohm-Sign m. The results show slight differences in morphologies and thermoelectric properties for the films deposited at varying deposition potential. The increase in thermoelectrical properties of the recycled carbon fibre is in line with the development of using coated recycled fibre for thermoelectrical applications. - Graphical abstract: SEM image of an N-type thermoelectric recycled carbon fibre sheet with Bi{sub 2}Te{sub 3} coatings. Highlights: Black-Right-Pointing-Pointer N-type thermoelectric sheet is synthesis through the electrodeposition of Bi{sub 2}Te{sub 3}. Black-Right-Pointing-Pointer Bi{sub 2}Te{sub 3} composition can be controlled by varying the deposition voltage. Black-Right-Pointing-Pointer Seebeck coefficient and electrical properties of the combined sheet were reported. Black-Right-Pointing-Pointer Material characterisations of the deposits are done using XRD, SEM and EDX.

Pang, E.J.X. [Division of Materials, Mechanics and Structures, The University of Nottingham, University Park, Nottingham, NG7 2RD (United Kingdom)] [Division of Materials, Mechanics and Structures, The University of Nottingham, University Park, Nottingham, NG7 2RD (United Kingdom); Pickering, S.J., E-mail: stephen.pickering@nottingham.ac.uk [Division of Materials, Mechanics and Structures, The University of Nottingham, University Park, Nottingham, NG7 2RD (United Kingdom); Chan, A. [Division of Materials, Mechanics and Structures, The University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor Darul Ehsan (Malaysia)] [Division of Materials, Mechanics and Structures, The University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor Darul Ehsan (Malaysia); Wong, K.H. [Division of Materials, Mechanics and Structures, The University of Nottingham, University Park, Nottingham, NG7 2RD (United Kingdom)] [Division of Materials, Mechanics and Structures, The University of Nottingham, University Park, Nottingham, NG7 2RD (United Kingdom); Lau, P.L. [Division of Materials, Mechanics and Structures, The University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor Darul Ehsan (Malaysia)] [Division of Materials, Mechanics and Structures, The University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor Darul Ehsan (Malaysia)

2012-09-15T23:59:59.000Z

370

Spectrum and Charge Ratio of Vertical Cosmic Ray Muons up to Momenta of 2.5 TeV/c  

SciTech Connect

The ALEPH detector at LEP has been used to measure the momentum spectrum and charge ratio of vertical cosmic ray muons underground. The sea-level cosmic ray muon spectrum for momenta up to 2.5 TeV/c has been obtained by correcting for the overburden of 320 meter water equivalent (mwe). The results are compared with Monte Carlo models for air shower development in the atmosphere. From the analysis of the spectrum the total flux and the spectral index of the cosmic ray primaries is inferred. The charge ratio suggests a dominantly light composition of cosmic ray primaries with energies up to 10{sup 15} eV.

Schmelling, M.; /Heidelberg, Max Planck Inst.; Hashim, N.O.; /Kenyatta U. Coll.; Grupen, C.; /Siegen U.; Luitz, S.; /SLAC; Maciuc, F.; /Heidelberg, Max Planck Inst.; Mailov, A.; /Siegen U.; Muller, A.-S.; /Karlsruhe, Inst. Technol.; Sander, H.-G.; /Mainz U., Inst. Phys.; Schmeling, S.; /CERN; Tcaciuc, R.; /Siegen U.; Wachsmuth, H.; /CERN; Zuber, K.; /Dresden, Tech. U.

2012-09-14T23:59:59.000Z

371

Appendix B: CArBon dioxide CApture teChnology SheetS Oxy-COmbustiOn  

NLE Websites -- All DOE Office Websites (Extended Search)

Oxy-COmbustiOn Oxy-COmbustiOn B-424 Oxy-COmbustiOn u.s. Department Of energy aDvanCeD CarbOn DiOxiDe Capture r&D prOgram: teChnOlOgy upDate, may 2013 Oxygen transpOrt membranes fOr inDustrial appliCatiOns primary project goals Praxair is optimizing oxygen transport membrane (OTM) performance, materials, and process configurations leading to subsequent development-scale testing of OTM technology for synthesis gas (syngas) production applications, providing valuable experience needed to develop commercial OTM technology in industrial applications and future utility-scale

372

Self-assembled formation and transformation of In/CdZnTe(110) nano-rings into camel-humps  

Science Conference Proceedings (OSTI)

We used in situ scanning tunneling microscopy to monitor in real time the formation of nano-rings at the molecular beam epitaxially grown In/CdZnTe(110) surface, and Auger electron spectroscopy to explore the corresponding compositional changes. In-diffusion of In and segregation of Cd to the surface in course of annealing lead to a formation of elliptically distorted nano-rings, elongated along the fast [110] diffusion direction. Exacerbated diffusion anisotropy in the liquid state, at temperatures above the melting point of In, further distorts the nano-rings into a camel-hump shape.

Cohen-Taguri, G. [School of Mechanical Engineering and Materials and Nanotechnologies Program, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978 (Israel); Ruzin, A. [School of Electrical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978 (Israel); Goldfarb, I. [School of Mechanical Engineering and Materials and Nanotechnologies Program, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978 (Israel); Research Center for Nanoscience and Nanotechnology, Tel Aviv University, Tel Aviv 69978 (Israel)

2012-05-21T23:59:59.000Z

373

Search for a fermiophobic Higgs boson in pp collisions at sqrt(s) = 7 TeV  

E-Print Network (OSTI)

Combined results are reported from searches for a fermiophobic Higgs boson in the gamma-gamma, WW, and ZZ decay modes in proton-proton collisions at sqrt(s) = 7 TeV. The explored Higgs boson mass range is 110-300 GeV. The data sample corresponds to an integrated luminosity of 4.9-5.1 inverse femtobarns. A fermiophobic Higgs boson is excluded at 95% confidence level in the mass range 110-194 GeV, and at 99% confidence level in the mass ranges 110-124.5 GeV, 127-147.5 GeV, and 155-180 GeV.

CMS Collaboration

2012-07-04T23:59:59.000Z

374

The microstructure network and thermoelectric properties of bulk (Bi,Sb){sub 2}Te{sub 3}  

Science Conference Proceedings (OSTI)

We report small-angle neutron scattering studies on the microstructure network in bulk (Bi,Sb){sub 2}Te{sub 3} synthesized by the melt-spinning (MS) and the spark-plasma-sintering (SPS) process. We find that rough interfaces of multiscale microstructures generated by the MS are responsible for the large reduction of both lattice thermal conductivity and electrical conductivity. Our study also finds that subsequent SPS forms a microstructure network of {approx}10 nm thick lamellae and smooth interfaces between them. This nanoscale microstructure network with smooth interfaces increases electrical conductivity while keeping a low thermal conductivity, making it an ideal microstructure for high thermoelectric efficiency.

Xie Wenjie [Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634 (United States); State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Hitchcock, Dale A.; Kang, Hye J.; He Jian [Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634 (United States); Tang Xinfeng [State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Laver, Mark [Department of Physics, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); Nano-Science Center, Niels Bohr Institute, University of Copenhagen, DK-2100 Kobenhavn (Denmark); Laboratory for Neutron Scattering, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Hammouda, Boualem [NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)

2012-09-10T23:59:59.000Z

375

Characterization of Min-K TE-1400 Thermal Insulation (Two-Year Gradient Stress Relaxation Testing Update)  

Science Conference Proceedings (OSTI)

Min-K 1400TE insulation material was characterized at Oak Ridge National Laboratory for use in structural applications under gradient temperature conditions. A previous report (ORNL/TM-2008/089) discusses the testing and results from the original three year duration of the project. This testing included compression testing to determine the effect of sample size and test specimen geometry on the compressive strength of Min-K, subsequent compression testing on cylindrical specimens to determine loading rates for stress relaxation testing, isothermal stress relaxation testing, and gradient stress relaxation testing. This report presents the results from the continuation of the gradient temperature stress relaxation testing and the resulting updated modeling.

Hemrick, James Gordon [ORNL; Lara-Curzio, Edgar [ORNL; King, James [ORNL

2009-09-01T23:59:59.000Z

376

Prompt TeV Emission from Cosmic Rays Accelerated by Gamma Ray Bursts Interacting with Surrounding Stellar Wind  

E-Print Network (OSTI)

Protons accelerated in the internal shocks of a long duration gamma ray burst can escape the fireball as cosmic rays by converting to neutrons. Hadronic interactions of these neutrons inside a stellar wind bubble created by the progenitor star will produce TeV gamma rays via neutral meson decay and synchrotron radiation by charged pion-decay electrons in the wind magnetic field. Such gamma rays should be observable from nearby gamma ray bursts by currently running and upcoming ground-based detectors.

Soebur Razzaque; Olga Mena; Charles D. Dermer

2008-10-07T23:59:59.000Z

377

Where the Sidewalk Ends: Jets and Missing Energy Search Strategies for the 7 TeV LHC  

SciTech Connect

This work explores the potential reach of the 7 TeV LHC to new colored states in the context of simplified models and addresses the issue of which search regions are necessary to cover an extensive set of event topologies and kinematic regimes. This article demonstrates that if searches are designed to focus on specific regions of phase space, then new physics may be missed if it lies in unexpected corners. Simple multiregion search strategies can be designed to cover all of kinematic possibilities. A set of benchmark models are created that cover the qualitatively different signatures and a benchmark multiregion search strategy is presented that covers these models.

Alves, Daniele S.M.; Izaguirre, Eder; Wacker, Jay G.; /SLAC /Stanford U., ITP

2011-08-15T23:59:59.000Z

378

Energy-momentum uncertainties as possible origin of threshold anomalies in UHECR and TeV-gamma ray events  

E-Print Network (OSTI)

A threshold anomaly refers to a theoretically expected energy threshold that is not observed experimentally. Here we offer an explanation of the threshold anomalies encountered in the ultra-high energy cosmic ray events and the TeV-gamma ray events, by arguing that energy-momentum uncertainties due to quantum gravity, too small to be detected in low-energy regime, can affect particle kinematics so as to raise or even eliminate the energy thresholds. A possible modification of the energy-momentum dispersion relation, giving rise to time-of-flight differences between photons of different energies from gamma ray bursts, is also discussed.

Y. Jack Ng; D. -S. Lee; M. C. Oh; H. van Dam

2000-10-15T23:59:59.000Z

379

An ab initio study of the electronic structure and optical properties of CdS{sub 1-x}Te{sub x} alloys  

Science Conference Proceedings (OSTI)

The structural, electronic and optical properties of cubic CdS{sub 1-x}Te{sub x} alloys, with Te-concentrations varying from 0% up to 100% are investigated. The calculations are based on the total-energy calculations using the full potential-linearized augmented plane wave (FP-LAPW) method. The exchange and correlation potential is treated by the generalized-gradient approximation (GGA) for the total-energy calculations, while for electronic properties in addition to that the Engel-Vosko (EV-GGA) formalism was also applied. The ground state properties for all Te-concentrations are presented. The optical dielectric constant is also determined for both the binary and their related ternary alloys. (author)

Al-Douri, Y.; Ahmad, S.; Hashim, U. [Institute of Nano Electronic Engineering, University Malaysia Perlis, Kangar, Perlis (Malaysia); Reshak, Ali Hussain [Institute of Nano Electronic Engineering, University Malaysia Perlis, Kangar, Perlis (Malaysia); Institute of Physical Biology, South Bohemia University, Nove Hrady (Czech Republic); Baaziz, H.; Charifi, Z. [Physics Department, Faculty of Science and Engineering, University of M'sila (Algeria); Khenata, R. [Laboratoire de Physique Quantique et de Modelisation Mathematique (LPQ3M), Universite de Mascara (Algeria); Department of Physics and Astronomy, Faculty of Science, King Saud University, Riyadh (Saudi Arabia)

2010-12-15T23:59:59.000Z

380

Thermodynamic, Raman and electrical switching studies on Si{sub 15}Te{sub 85-x}Ag{sub x} (4 {<=} x {<=} 20) glasses  

Science Conference Proceedings (OSTI)

We have investigated thermal properties of bulk Si{sub 15}Te{sub 85-x}Ag{sub x} (4 {data obtained from different thermodynamic quantities and it is found that the Si{sub 15}Te{sub 85-x}Ag{sub x} glasses in the region 12 {<=} x {<=} 17 are more stable when compared to other glasses of the same series. Further, the blueshift observed in Raman spectroscopy investigations, in the composition range 12 {<=} x {<=} 13, support the occurrence of stiffness threshold in this composition range. All Si{sub 15}Te{sub 85-x}Ag{sub x} (4 {<=} x {<=} 20) glasses are found to exhibit memory type switching (for sample thickness 0.25 mm) in the input current range 3-9 mA. The effect of rigidity percolation and chemical thresholds on switching voltages are observed at x = 12 and 19, respectively.

Rao Gunti, Srinivasa [Department of Instrumentation and Applied Physics, Indian Institute of Science, Bangalore 560012 (India); Asokan, Sundarrajan [Department of Instrumentation and Applied Physics, Indian Institute of Science, Bangalore 560012 (India); Applied Photonics Initiative, Indian Institute of Science, Bangalore 560012 (India)

2012-02-01T23:59:59.000Z

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381

High Efficiency Thin Film CdTe and a-Si Based Solar Cells: Final Technical Report, 4 March 1998--15 October 2001  

DOE Green Energy (OSTI)

This is the final report covering about 42 months of this subcontract for research on high-efficiency CdTe-based thin-film solar cells and on high-efficiency a-Si-based thin-film solar cells. Phases I and II have been extensively covered in two Annual Reports. For this Final Report, highlights of the first two Phases will be provided and then detail will be given on the last year and a half of Phase III. The effort on CdTe-based materials is led by Prof. Compaan and emphasizes the use of sputter deposition of the semiconductor layers in the fabrication of CdS/CdTe cells. The effort on high-efficiency a-Si materials is led by Prof. Deng and emphasizes plasma-enhanced chemical vapor deposition for cell fabrication with major efforts on triple-junction devices.

Compaan, A. D.; Deng, X.; Bohn, R. G.

2003-10-01T23:59:59.000Z

382

COMPACT CdZnTe-BASED GAMMA CAMERA FOR PROSTATE CANCER IMAGING  

SciTech Connect

In this paper, we discuss the design of a compact gamma camera for high-resolution prostate cancer imaging using Cadmium Zinc Telluride (CdZnTe or CZT) radiation detectors. Prostate cancer is a common disease in men. Nowadays, a blood test measuring the level of prostate specific antigen (PSA) is widely used for screening for the disease in males over 50, followed by (ultrasound) imaging-guided biopsy. However, PSA tests have a high false-positive rate and ultrasound-guided biopsy has a high likelihood of missing small cancerous tissues. Commercial methods of nuclear medical imaging, e.g. PET and SPECT, can functionally image the organs, and potentially find cancer tissues at early stages, but their applications in diagnosing prostate cancer has been limited by the smallness of the prostate gland and the long working distance between the organ and the detectors comprising these imaging systems. CZT is a semiconductor material with wide band-gap and relatively high electron mobility, and thus can operate at room temperature without additional cooling. CZT detectors are photon-electron direct-conversion devices, thus offering high energy-resolution in detecting gamma rays, enabling energy-resolved imaging, and reducing the background of Compton-scattering events. In addition, CZT material has high stopping power for gamma rays; for medical imaging, a few-mm-thick CZT material provides adequate detection efficiency for many SPECT radiotracers. Because of these advantages, CZT detectors are becoming popular for several SPECT medical-imaging applications. Most recently, we designed a compact gamma camera using CZT detectors coupled to an application-specific-integrated-circuit (ASIC). This camera functions as a trans-rectal probe to image the prostate gland from a distance of only 1-5 cm, thus offering higher detection efficiency and higher spatial resolution. Hence, it potentially can detect prostate cancers at their early stages. The performance tests of this camera have been completed. The results show better than 6-mm resolution at a distance of 1 cm. Details of the test results are discussed in this paper.

CUI, Y.; LALL, T.; TSUI, B.; YU, J.; MAHLER, G.; BOLOTNIKOV, A.; VASKA, P.; DeGERONIMO, G.; O' CONNOR, P.; MEINKEN, G.; JOYAL, J.; BARRETT, J.; CAMARDA, G.; HOSSAIN, A.; KIM, K.H.; YANG, G.; POMPER, M.; CHO, S.; WEISMAN, K.; SEO, Y.; BABICH, J.; LaFRANCE, N.; AND JAMES, R.B.

2011-10-23T23:59:59.000Z

383

Transport and deposition of functionalized CdTe nanoparticles in saturated porous media  

SciTech Connect

Comprehensive understanding of the transport and deposition of engineered nanoparticles (NPs) in subsurface is required to assess their potential negative impact on the environment. We studied the deposition behavior of functionalized quantum dot (QD) NPs (CdTe) in different types of sands (Accusand, ultrapure quartz, and iron-coated sand) at various solution ionic strengths (IS). The observed transport behavior in ultrapure quartz and iron-coated sand was consistent with conventional colloid deposition theories. However, our results from the Accusand column showed that deposition was minimal at the lowest IS (1 mM) and increased significantly as the IS increased. The effluent breakthrough occurred with a delay, followed by a rapid rise to the maximum normalized concentration of unity. Negligible deposition in the column packed with ultrapure quartz sand (100 mM) and Accusand (1 mM) rules out the effect of straining and suggests the importance of surface charge heterogeneity in QD deposition in Accusand at higher IS. Data analyses further show that only a small fraction of sand surface area contributed in QD deposition even at the highest IS (100 mM) tested. The observed delay in breakthrough curves of QDs was attributed to the fast diffusive mass transfer rate of QDs from bulk solution to the sand surface and QD mass transfer on the solid phase. Scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) analysis were used to examine the morphology and elemental composition of sand grains. It was observed that there were regions on the sand covered with layers of clay particles. EDX spectra collected from these regions revealed that Si and Al were the major elements suggesting that the clay particles were kaolinite. Additional batch experiments using gold NPs and SEM analysis were performed and it was observed that the gold NPs were only deposited on clay particles originally on the Accusand surface. After removing the clays from the sand surface, we observed negligible QD deposition even at 100 mM IS. We proposed that nanoscale charge heterogeneities on clay particles on Accusand surface played a key role in QD deposition. It was shown that the value of solution IS determined the extent to which the local heterogeneities participated in particle deposition.

Torkzaban, S.; Wan, J.; Kim, Y.; Mulvihill, M.; Tokunaga, T. K.

2010-10-15T23:59:59.000Z

384

Physical properties, crystal and magnetic structure of layered Fe[subscript 1.11]Te[subscript 1;#8722;x]Se[subscript x] superconductors  

SciTech Connect

The physical and structural properties of Fe1.11Te and Fe1.11Te0.5Se0.5 have been investigated by means of X-ray and neutron diffraction as well as physical property measurements. For the Fe1.11Te compound, the structure distortion from a tetragonal to monoclinic phase takes place at 64 K accompanied with the onset of antiferromagnetic order upon cooling. The magnetic structure of the monoclinic phase was confirmed to be of antiferromagnetic configuration with a propagation vector k = (1/2, 0, 1/2) based on Rietveld refinement of neutron powder diffraction data. The structural/magnetic transitions are also clearly visible in magnetic, electronic and thermodynamic measurements. For superconducting Fe1.11Te0.5Se0.5 compound, the superconducting transition with T c = 13.4 K is observed in the resistivity and ac susceptibility measurements. The upper critical field H c2 is obtained by measuring the resistivity under different magnetic fields. The Kim's critical state model is adopted to analyze the temperature dependence of the ac susceptibility and the intergranular critical current density is calculated as a function of both field amplitude and temperature. Neutron diffraction results show that Fe1.11Te0.5Se0.5 crystalizes in tetragonal structure at 300 K as in the parent compound Fe1.11Te and no structural distortion is detected upon cooling to 2 K. However an anisotropic thermal expansion anomaly is observed around 100 K.

Xiao, Y.; Su, Y.; Kumar, C.M.N.; Ritter, C.; Mittal, R.; Price, S.; Peron, J.; Brckel, Th. (BARC); (Julich); (ILL)

2012-10-23T23:59:59.000Z

385

The Present, Mid-Term, and Long-Term Supply Curves for Tellurium; and Updates in the Results from NREL's CdTe PV Module Manufacturing Cost Model (Presentation)  

Science Conference Proceedings (OSTI)

For those PV technologies that rely upon Te, In, and Ga, first-order observations and calculations hint that there may be resource constraints that could inhibit their successful deployment at a SunShot level. These are only first-order approximations, however, and the possibility for an expansion in global Te, In, and Ga supplies needs to be considered in the event that there are upward revisions in their demand and prices.In this study, we examine the current, mid-term, and long-term prospects of Tellurium (Te) for use in PV. We find that the current global supply base of Te would support supply base for Te might be expanded, after compiling several preliminary cumulative availability curves we find that there may be significant upside potential in the supply base for this element - principally vis a vis increasing demand and higher prices. Primarily by reducing the Tellurium intensity in manufacturing and by increasing the recovery efficiency of Te in Cu refining processes, we calculate that it may prove affordable to PV manufacturers to expand the supply base for Te such that 100 GW, or greater, of annual CdTe PV production is possible in the 2030 - 2050 timeframe.

Woodhouse, M.; Goodrich, A.; Redlinger, M.; Lokanc, M.; Eggert, R.

2013-09-01T23:59:59.000Z

386

High-throughput manufacturing of thin-film CdS/CdTe photovoltaic modules. Annual subcontract report, 16 September 1996--15 January 1998  

DOE Green Energy (OSTI)

Cadmium telluride (CdTe) is recognized as one of the leading materials for low-cost photovoltaic modules. Solar Cells, Inc., has developed this technology and is scaling its pilot production capabilities to a multi-megawatt level. The Photovoltaic Manufacturing Technology (PVMaT) subcontract supports these efforts. Activities during the third phase of the program concentrated on process development, equipment design and testing, quality assurance, ES and H programs, and large-scale next-generation coating-system prototype development. These efforts broadly addressed the issues of the manufacturing process for producing thin-film, monolithic CdS/CdTe photovoltaic modules.

Sandwisch, D.W. [Solar Cells, Inc., Toledo, OH (United States)

1998-08-01T23:59:59.000Z

387

Propane ammoxidation over the Mo-V-Te-Nb-O M1 phase: Reactivity of surface cations in hydrogen abstraction steps  

Science Conference Proceedings (OSTI)

Density functional theory calculations (GGA-PBE) have been performed to investigate the adsorption of C3 (propane, isopropyl, propene, and allyl) and H species on the proposed active center present in the surface ab planes of the bulk Mo-V-Te-Nb-O M1 phase in order to better understand the roles of the different surface cations in propane ammoxidation. Modified cluster models were employed to isolate the closely spaced V=O and Te=O from each other and to vary the oxidation state of the V cation. While propane and propene adsorb with nearly zero adsorption energy, the isopropyl and allyl radicals bind strongly to V=O and Te=O with adsorption energies, {Delta}E, being {le} -1.75 eV, but appreciably more weakly on other sites, such as Mo=O, bridging oxygen (Mo-O-V and Mo-O-Mo), and empty metal apical sites ({Delta}E > -1 eV). Atomic H binds more strongly to Te = O ({Delta}E {le} -3 eV) than to all the other sites, including V = O ({Delta}E = -2.59 eV). The reduction of surface oxo groups by dissociated H and their removal as water are thermodynamically favorable except when both H atoms are bonded to the same Te=O. Consistent with the strong binding of H, Te=O is markedly more active at abstracting the methylene H from propane (E{sub a} {le} 1.01 eV) than V = O (E{sub a} = 1.70 eV on V{sup 5+} = O and 2.13 eV on V{sup 4+} = O). The higher-than-observed activity and the loose binding of Te = O moieties to the mixed metal oxide lattice of M1 raise the question of whether active Te = O groups are in fact present in the surface ab planes of the M1 phase under propane ammoxidation conditions.

Muthukumar, Kaliappan [University of Cincinnati; Yu, Junjun [University of Cincinnati; Xu, Ye [ORNL; Guliants, Vadim V. [University of Cincinnati

2011-01-01T23:59:59.000Z

388

Measurement of the strange - antistrange asymmetry at NLO in QCD from NuTeV dimuon data  

SciTech Connect

A measurement of the asymmetry between the strange and antistrange quark distributions, from a next to leading order QCD analysis of dimuon events measured by the NuTeV experiment at Fermilab is presented. Neutrino charged current events with two muons in the final state provide a direct means for studying charm production and measuring the strange sea. NuTeV's sign selected beam allows independent measurement of the strange and antistrange seas. An improved measurement of the neutrino and antineutrino forward dimuon cross section tables, using the complete charged current event sample for normalization is performed. These tables are then analyzed at NLO to measure the strange and antistrange seas. Detector acceptance is modeled using an NLO charm cross section differential in all variables required. The strange quark distribution is found to have an integrated momentum weighted asymmetry of +0.00196 {+-} 0.00046(stat) {+-} 0.00045(syst) {+-} 0.00182(external). The charm mass is found to be 1.41 {+-} 0.10(stat) {+-} 0.08(syst) {+-} 0.12(external) GeV.

Mason, David Alexander; /Oregon U.

2006-03-01T23:59:59.000Z

389

Modeling of 10 GeV-1 TeV laser-plasma accelerators using Lorentz booster simulations  

SciTech Connect

Modeling of laser-plasma wakefield accelerators in an optimal frame of reference [J.-L. Vay, Phys. Rev. Lett. 98 130405 (2007)] allows direct and e#14;fficient full-scale modeling of deeply depleted and beam loaded laser-plasma stages of 10 GeV-1 TeV (parameters not computationally accessible otherwise). This verifies the scaling of plasma accelerators to very high energies and accurately models the laser evolution and the accelerated electron beam transverse dynamics and energy spread. Over 4, 5 and 6 orders of magnitude speedup is achieved for the modeling of 10 GeV, 100 GeV and 1 TeV class stages, respectively. Agreement at the percentage level is demonstrated between simulations using different frames of reference for a 0.1 GeV class stage. Obtaining these speedups and levels of accuracy was permitted by solutions for handling data input (in particular particle and laser beams injection) and output in a relativistically boosted frame of reference, as well as mitigation of a high-frequency instability that otherwise limits effectiveness.

Vay, J.-L.; Geddes, C.G.R.; Esarey, E.; Esarey, E.; Leemans, W.P.; Cormier-Michel, E.; Grote, D.P.

2011-12-01T23:59:59.000Z

390

Yrast state band of even 120-130Te isotopes under the framework of interacting boson model -1  

E-Print Network (OSTI)

In this paper, nuclear structure of yrast state bands of even-even 120-130Te isotopes has been studied under the frame work of interacting boson model (IBM-1). The theoretical energy levels for Z=52, even N = 68-78 up to 12+ state have been obtained by using the MatLab 6.5 computer program. The ratio of the excitation energies of first 4+ and first 2+ excited states, R4/2, has been also calculated for those nuclei. The values of the parameters in the IBM-1 hamiltonian yield the best fit to the experimental energy spectrum. The results are compared with the most recent experimental values where an acceptable degree of agreement is achieved. Moreover, as a measure to quantify the evolution, we have studied the transition rate R of some of the low-lying quadrupole collective states in comparison to the available experimental data. In this paper, the properties of even 120-130Te isotopes have been considered to the U(5) transitional region of IBM-1.

I Hossain; Hewa Y Abdullah; I M Ahmed; J Islam

2013-10-10T23:59:59.000Z

391

Yrast state band of even 120-130Te isotopes under the framework of interacting boson model -1  

E-Print Network (OSTI)

In this paper, nuclear structure of yrast state bands of even-even 120-130Te isotopes has been studied under the frame work of interacting boson model (IBM-1). The theoretical energy levels for Z=52, even N = 68-78 up to 12+ state have been obtained by using the MatLab 6.5 computer program. The ratio of the excitation energies of first 4+ and first 2+ excited states, R4/2, has been also calculated for those nuclei. The values of the parameters in the IBM-1 hamiltonian yield the best fit to the experimental energy spectrum. The results are compared with the most recent experimental values where an acceptable degree of agreement is achieved. Moreover, as a measure to quantify the evolution, we have studied the transition rate R of some of the low-lying quadrupole collective states in comparison to the available experimental data. In this paper, the properties of even 120-130Te isotopes have been considered to the U(5) transitional region of IBM-1.

Hossain, I; Ahmed, I M; Islam, J

2013-01-01T23:59:59.000Z

392

Biodistribution of radioactive Cd125mTe/ZnS nanoparticles targeted with antibody to murine lung endothelium.  

Science Conference Proceedings (OSTI)

Radioactive cadmium telluride/zinc sulfide (Cd{sup 125m}Te/ZnS) nanoparticles were targeted to mouse lung with antibody to mouse lung endothelium and quantified using radiological histology in order to test the in vivo targeting efficacy of a nanoparticle-antibody (NP-mAb) system. The nanoparticles were linked to either a monoclonal antibody to mouse lung thrombomodulin (mAb 201B) or a control antibody (mAb 33), and injected into groups of 6-week-old Balb/C female mice. Animals were sacrificed at 1, 4, 24, 72 and 144 h post-injection, and biodistribution in major organs was determined. Full body microSPECT/CT imaging was performed on a pair of mice (experimental and control) providing visual confirmation of the biodistribution. The Cd{sup 125m}Te/ZnS NPs conjugated to mAb 201B principally target the lungs while the nanoparticles coupled to mAb 33 accumulate in the liver and spleen. These data provide, for the first time, a quantitative measurement of the in vivo targeting efficacy of an inorganic nanoparticle-mAb system.

Woodward, Jonathan [ORNL; Kennel, Steve J [ORNL; Mirzadeh, Saed [ORNL; Dai, Sheng [ORNL; Rondinone, Adam Justin [ORNL

2007-01-01T23:59:59.000Z

393

Experimental investigations of the TE{sub 11} mode radiation from a relativistic magnetron with diffraction output  

Science Conference Proceedings (OSTI)

Directly radiating microwaves at TE{sub 11} mode, a relativistic magnetron with diffraction output (MDO) is experimentally investigated. Two important factors, transition section and working condition, significantly affecting the microwave powers, efficiencies, and pulse durations are analyzed. The experimental results on our designed MDO show that the optimized transition section with the parameters, 46 mm in height and 70 mm in length, is beneficial for producing high power TE{sub 11} mode microwaves. Under the low applied voltage condition (less than 650 kV), the power conversion efficiency will be higher than that obtained from the high applied voltage condition. {approx}24 ns of the microwave duration is a typical value under the voltage duration of 56 ns. Pulse shortens will happen if the applied voltage is higher than 650 kV. When the applied voltage reaches 880 kV, the microwave duration is only just {approx}12 ns. Impendence mismatch between the accelerator and the diode is the chief reason causing the pulse shortens.

Li Wei; Liu Yonggui; Zhang Jun; Yang Hanwu; Qian Baoliang [College of Optoelectric Science and Engineering, National University of Defense Technology, Changsha, Hunan 410073 (China)

2012-11-15T23:59:59.000Z

394

TeV blazar gamma-ray emission produced by a cooling pile-up particle energy distribution function  

E-Print Network (OSTI)

We propose a time-dependent one-zone model based on a quasi-Maxwellian `pile-up' distribution in order to explain the time-averaged high energy emission of TeV blazars. The instantaneous spectra are the result of the synchrotron and synchrotron self-Compton emission (SSC) of ultra-relativistic leptons. The particle energy distribution function (EDF) is computed in a self-consistent way, taking into account an injection term of fresh particles, a possible pair creation term, and the particles radiative cooling. The source term is not a usual power-law but rather a `pile-up' distribution, which can result from the combination of a stochastic heating via second order Fermi process and radiative cooling. To validate this approach, we have performed time-averaged fits of the well-known TeV emitter Mrk 501 during the 1997 flaring activity period taking into account the attenuation of the high energy component by cosmic diffuse infrared background (DIrB) and intrinsic absorption via the pair creation process. The model can reproduce very satisfactorily the observed spectral energy distribution (SED). A high Lorentz factor is required to avoid strong pair production; in the case of smaller Lorentz factor, an intense flare in the GeV range is predicted due to the sudden increase of soft photons density below the Klein-Nishina threshold. The possible relevance of such a scenario is discussed.

Ludovic Sauge; Gilles Henri

2004-08-12T23:59:59.000Z

395

Non-zero U_{e3} and TeV-Leptogenesis through A_4 symmetry breaking  

E-Print Network (OSTI)

We consider an effective theory with an $SU(2)\\times U(1)\\times A_{4}\\times Z_{2}\\times Z_{4}$ symmetry and investigate the possibility of a linking TeV-leptogenesis with a reactor angle $|U_{e3}|$ through spontaneous $A_{4}$ symmetry breaking which is at a scale higher than electroweak scale under the framework of radiative seesaw. It has been shown that tri-bimaximal(TBM) can be obtained by forging vacuum expectation value (VEV) alignment of the $A_{4}$. Especially, one $A_{4}$ triplet scalar field with cut-off scale $\\Lambda$ is added in neutrino Yukawa sector, which is responsible for the deviation of the exact TBM, to explain leptogenesis as well as a non-zero $|U_{e3}|$. Above the scale of $\\Lambda$ the leptonic Yukawa sectors will lead to the exact TBM. We analyze possible spectrums of light neutrinos and their flavor mixing angles corresponding to heavy Majorana neutrino mass ordering, and show that non-resonance leptogenesis at TeV-scale constrained by low energy data is achievable, both analytically as well as numerically. We show that only normal hierarchical spectrum of light neutrino would be strongly favored by the current Wilkinson Microwave Anisotropy Probe (WMAP) data, and also show that a relatively large $|U_{e3}|$ corresponds to the value of baryon asymmetry $6.2\\times10^{-10}$.

Y. H. Ahn; Chian-Shu Chen

2010-01-17T23:59:59.000Z

396

Non-zero U_{e3} and TeV-Leptogenesis through A_4 symmetry breaking  

E-Print Network (OSTI)

We consider an effective theory with an $SU(2)\\times U(1)\\times A_{4}\\times Z_{2}\\times Z_{4}$ symmetry and investigate the possibility of a linking TeV-leptogenesis with a reactor angle $|U_{e3}|$ through spontaneous $A_{4}$ symmetry breaking which is at a scale higher than electroweak scale under the framework of radiative seesaw. It has been shown that tri-bimaximal(TBM) can be obtained by forging vacuum expectation value (VEV) alignment of the $A_{4}$. Especially, one $A_{4}$ triplet scalar field with cut-off scale $\\Lambda$ is added in neutrino Yukawa sector, which is responsible for the deviation of the exact TBM, to explain leptogenesis as well as a non-zero $|U_{e3}|$. Above the scale of $\\Lambda$ the leptonic Yukawa sectors will lead to the exact TBM. We analyze possible spectrums of light neutrinos and their flavor mixing angles corresponding to heavy Majorana neutrino mass ordering, and show that non-resonance leptogenesis at TeV-scale constrained by low energy data is achievable, both analytically...

Ahn, Y H

2010-01-01T23:59:59.000Z

397

MODELING PHOTODISINTEGRATION-INDUCED TeV PHOTON EMISSION FROM LOW-LUMINOSITY GAMMA-RAY BURSTS  

Science Conference Proceedings (OSTI)

Ultra-high-energy cosmic-ray heavy nuclei have recently been considered as originating from nearby low-luminosity gamma-ray bursts that are associated with Type Ibc supernovae. Unlike the power-law decay in long duration gamma-ray bursts, the light curve of these bursts exhibits complex UV/optical behavior: shock breakout dominated thermal radiation peaks at about 1 day, and, after that, nearly constant emission sustained by radioactive materials for tens of days. We show that the highly boosted heavy nuclei at PeV energy interacting with the UV/optical photon field will produce considerable TeV photons via the photodisintegration/photo-de-excitation process. It was later predicted that a thermal-like {gamma}-ray spectrum peaks at about a few TeV, which may serve as evidence of nucleus acceleration. The future observations by the space telescope Fermi and by the ground atmospheric Cherenkov telescopes such as H.E.S.S., VERITAS, and MAGIC will shed light on this prediction.

Liu Xuewen [Physics Department, Sichuan University, Chengdu 610065 (China); Wu Xuefeng; Lu Tan, E-mail: astrolxw@gmail.com, E-mail: xfwu@pmo.ac.cn, E-mail: t.lu@pmo.ac.cn [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)

2012-05-15T23:59:59.000Z

398

Measurement of the ATLAS di-muon trigger efficiency in proton-proton collisions at 7 TeV  

E-Print Network (OSTI)

At the LHC, muons are produced in many final states and used in a variety of analysis, such as Standard Model precision measurements and searches for new physics. The B-physics programme in ATLAS includes the measurement of CP violating effects in B meson decays, the search for rare b decay signatures, as well as the study of the production cross sections. The ATLAS detector can identify muons with high purity in a transverse momentum ($p_{T}$) range from a few GeV to several TeV. In order to achieve a high trigger efficiency for low $p_{T}$ di-muon events and at the same time keep an acceptable trigger rate, dedicated trigger algorithms have been designed and implemented in the trigger menu since the 2010 data taking period. There are two categories of B-physics triggers, one topological and one non-topological. Both of these have been studied and their performance assessed using collision data at $\\sqrt{s}$ = 7 TeV. The performance found with data has been verified with simulated events.

E. Piccaro; On Behalf of the ATLAS Collaboration

2011-11-18T23:59:59.000Z

399

Sensitivity of the High Altitude Water Cherenkov Detector to Sources of Multi-TeV Gamma Rays  

E-Print Network (OSTI)

The High Altitude Water Cherenkov (HAWC) observatory is an array of large water Cherenkov detectors sensitive to gamma rays and hadronic cosmic rays in the energy band between 100 GeV and 100 TeV. The observatory will be used to measure high-energy protons and cosmic rays via detection of the energetic secondary particles reaching the ground when one of these particles interacts in the atmosphere above the detector. HAWC is under construction at a site 4100 meters above sea level on the northern slope of the volcano Sierra Negra, which is located in central Mexico at 19 degrees N latitude. It is scheduled for completion in 2014. In this paper we estimate the sensitivity of the HAWC instrument to point-like and extended sources of gamma rays. The source fluxes are modeled using both unbroken power laws and power laws with exponential cutoffs. HAWC, in one year, is sensitive to point sources with integral power-law spectra as low as 5x10^-13 cm^-2 sec^-1 above 2 TeV (approximately 50 mCrab) over 5 sr of the sky...

Abeysekara, A U; Alvarez, C; lvarez, J D; Arceo, R; Arteaga-Velzquez, J C; Solares, H A Ayala; Barber, A S; Baughman, B M; Bautista-Elivar, N; Belmont, E; BenZvi, S Y; Berley, D; Rosales, M Bonilla; Braun, J; Caballero-Lopez, R A; Carramiana, A; Castillo, M; Cotti, U; Cotzomi, J; de la Fuente, E; De Len, C; DeYoung, T; Hernandez, R Diaz; Diaz-Velez, J C; Dingus, B L; DuVernois, M A; Ellsworth, R W; Fernandez, A; Fiorino, D W; Fraija, N; Galindo, A; Garcia-Luna, J L; Garcia-Torales, G; Garfias, F; Gonzlez, L X; Gonzlez, M M; Goodman, J A; Grabski, V; Gussert, M; Hampel-Arias, Z; Hui, C M; Hntemeyer, P; Imran, A; Iriarte, A; Karn, P; Kieda, D; Kunde, G J; Lara, A; Lauer, R J; Lee, W H; Lennarz, D; Vargas, H Len; Linares, E C; Linnemann, J T; Longo, M; Luna-Garc\\'\\ia, R; Marinelli, A; Martinez, O; Mart\\'\\inez-Castro, J; Matthews, J A J; Miranda-Romagnoli, P; Moreno, E; Mostaf, M; Nava, J; Nellen, L; Newbold, M; Noriega-Papaqui, R; Oceguera-Becerra, T; Patricelli, B; Pelayo, R; Prez-Prez, E G; Pretz, J; Rivire, C; Rosa-Gonzlez, D; Salazar, H; Salesa, F; Sandoval, A; Santos, E; Schneider, M; Silich, S; Sinnis, G; Smith, A J; Sparks, K; Springer, R W; Taboada, I; Toale, P A; Tollefson, K; Torres, I; Ukwatta, T N; Villaseor, L; Weisgarber, T; Westerhoff, S; Wisher, I G; Wood, J; Yodh, G B; Younk, P W; Zaborov, D; Zepeda, A; Zhou, H

2013-01-01T23:59:59.000Z

400

Features of the charge-transport mechanism in layered Bi{sub 2}Te{sub 3} single crystals doped with chlorine and terbium  

Science Conference Proceedings (OSTI)

The temperature dependences (T = 5-300 K) of the resistivity in the plane of layers and in the direction perpendicular to the layers, as well as the Hall effect and the magnetoresistance (H < 80 kOe, T = 0.5-4.2 K) in Bi{sub 2}Te{sub 3} single crystals doped with chlorine and terbium, are investigated. It is shown that the doping of Bi{sub 2}Te{sub 3} with terbium atoms results in p-type conductivity and in increasing hole concentration. The doping of Bi{sub 2}Te{sub 3} with chlorine atoms modifies also the character of its conductivity instead of changing only the type from p to n. In the temperature dependence of the resistivity in the direction perpendicular to layers, a portion arises with the activation conductivity caused by the hopping between localized states. The charge-transport mechanism in Bi{sub 2}Te{sub 3} single crystals doped with chlorine is proposed.

Abdullaev, N. A., E-mail: anadir@azintex.com; Abdullaev, N. M.; Aliguliyeva, H. V.; Kerimova, T. G.; Mehdiyev, G. S. [National Academy of Sciences of Azerbaijan, Abdullaev Institute of Physics (Azerbaijan); Nemov, S. A. [St. Petersburg State Polytechnic University (Russian Federation)

2011-01-15T23:59:59.000Z

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401

Search for Charged Higgs Bosons in Decays of Top Quarks in pp-bar Collisions at sqrt s=1.96 TeV  

E-Print Network (OSTI)

We report on the first direct search for charged Higgs bosons decaying into cs? in tt? events produced by pp? collisions at ?s=1.96??TeV. The search uses a data sample corresponding to an integrated luminosity of ...

Xie, Si

402

Proceedings of ICRC 2001: 1 c Copernicus Gesellschaft 2001 A Search for Bursts of TeV Gamma Rays with Milagro  

E-Print Network (OSTI)

Abstract. The Very High Energy (VHE, E > 100 GeV) component of Gamma-Ray Bursts (GRBs) remains unmea- suredV Gamma Rays with Milagro A.J. Smith for the Milagro Collaboration University of Maryland, College Park close enough to observe at TeV energies remains unknown. The Milagro Gamma Ray Obser- vatory began

California at Santa Cruz, University of

403

Search for a Higgs Boson in the Diphoton Final State in pp? Collisions at ?s=1.96??TeV  

E-Print Network (OSTI)

A search for a narrow Higgs boson resonance in the diphoton mass spectrum is presented based on data corresponding to 7.0??fb[superscript -1] of integrated luminosity from pp? collisions at ?s=1.96??TeV collected by the ...

Bauer, Gerry P.

404

Search for the Higgs Boson in the H?WW?l?jj Decay Channel in pp Collisions at ?s=7??TeV with the ATLAS Detector  

E-Print Network (OSTI)

A search for a Higgs boson has been performed in the H?WW???jj channel in 1.04??fb[superscript -1] of pp collision data at ?s=7??TeV recorded with the ATLAS detector at the Large Hadron Collider. No significant excess of ...

Taylor, Frank E.

405

Search for a Low-Mass Standard Model Higgs Boson in the ?? Decay Channel in pp? Collisions at ?s=1.96??TeV  

E-Print Network (OSTI)

We report on a search for the standard model Higgs boson decaying into pairs of ? leptons in pp? collisions produced by the Tevatron at ?s=1.96??TeV. The analyzed data sample was recorded by the CDFII detector and corresponds ...

Bauer, Gerry P.

406

Search for a Fermiophobic Higgs Boson Decaying into Diphotons in pp-bar Collisions at sqrt[s]=1.96 TeV  

E-Print Network (OSTI)

A search for a narrow diphoton mass resonance is presented based on data from 3.0??fb[superscript -1] of integrated luminosity from pp? collisions at ?s=1.96??TeV collected by the CDF experiment. No evidence of a resonance ...

Xie, Si

407

Search for a Standard Model Higgs Boson in WH-->lvbb-bar in pp-bar Collisions at sqrt[s]=1.96 TeV  

E-Print Network (OSTI)

We present a search for a standard model Higgs boson produced in association with a W boson using 2.7??fb[superscript -1] of integrated luminosity of pp? collision data taken at ?s=1.96??TeV. Limits on the Higgs boson ...

Xie, Si

408

High-Efficiency Polycrystalline CdTe Thin-Film Solar Cells with an Oxygenated Amorphous CdS (a-CdS:O) Window Layer: Preprint  

DOE Green Energy (OSTI)

In the conventional CdS/CdTe device structure, the poly-CdS window layer has a bandgap of {approx}2.4 eV, which causes absorption in the short-wavelength region. Higher short-circuit current densities (Jsc) can be achieved by reducing the CdS thickness, but this can adversely impact device open-circuit voltage (Voc) and fill factor (FF). Also, poly-CdS film has about 10% lattice mismatch related to the CdTe film, which limits the improvement of device Voc and FF. In this paper, we report a novel window material: oxygenated amorphous CdS film (a-CdS:O) prepared at room temperature by rf sputtering. The a-CdS:O film has a higher optical bandgap (2.5-3.1 eV) than the poly-CdS film and an amorphous structure. The preliminary device results have demonstrated that Jsc of the CdTe device can be greatly improved while maintaining higher Voc and FF. We have fabricated a CdTe cell demonstrating an NREL-confirmed Jsc of 25.85 mA/cm2 and a total-area efficiency of 15.4%.

Wu, X.; Dhere, R. G.; Yan, Y.; Romero, M. J.; Zhang, Y.; Zhou, J.; DeHart, C.; Duda, A.; Perkins, C.; To, B.

2002-05-01T23:59:59.000Z

409

Hidrofobikumo ?taka daikli? sorbcijai vilnos pluote ir daini? fizikin?ms savyb?ms.  

E-Print Network (OSTI)

??Baigiamojo darbo tikslas itirti vilnos pluoto paviriaus hidrofobikumo ?tak? daikli? sorbcijai vilnos pluote ir daini? fizikin?ms savyb?ms. Nauj? antrachinonini? daikli? RB 5-37 M?lynojo ir (more)

Gr?bli?nait?,; Egl?

2011-01-01T23:59:59.000Z

410

Theoretical Analysis of Effects of Deep Level, Back Contact, and Absorber Thickness on Capacitance-Voltage Profiling of CdTe Thin-Film Solar Cells  

Science Conference Proceedings (OSTI)

The apparent carrier density profile measured by the capacitance-voltage technique in CdTe thin-film solar cells frequently displays a distinctive U-shape. We show that, even assuming a uniform carrier density, such a U-shape may arise from deep levels, a non-ohmic back-contact, and a thin absorber, which are commonly present in practical CdTe thin-film solar cells. A thin CdTe absorber contributes to the right branch of the U-shape due to a punch-through effect at reverse or zero biases, when the CdTe absorber is nearly fully depleted. A rectifying back-contact contributes to both branches of the U-shape due to voltage sharing with the front junction under a forward bias and early punch-through under a reverse bias. Deep levels contribute to the right branch, but also raise the bottom of the U-shape, leading to an overestimate of carrier density.

Li, J. V.; Halverson, A. F.; Sulima, O. V.; Bansal, S.; Burst, J. M.; Barnes, T. M.; Gessert, T. A.; Levi, D. H.

2012-05-01T23:59:59.000Z

411

Adsorption of propane, isopropyl, and hydrogen on cluster models of the M1 phase of Mo-V-Te-Nb-O mixed metal oxide catalyst  

Science Conference Proceedings (OSTI)

The Mo-V-Te-Nb-O mixed metal oxide catalyst possessing the M1 phase structure is uniquely capable of directly converting propane into acrylonitrile. However, the mechanism of this complex eight-electron transformation, which includes a series of oxidative H-abstraction and N-insertion steps, remains poorly understood. We have conducted a density functional theory study of cluster models of the proposed active and selective site for propane ammoxidation, including the adsorption of propane, isopropyl (CH{sub 3}CHCH{sub 3}), and H which are involved in the first step of this transformation, that is, the methylene C-H bond scission in propane, on these active site models. Among the surface oxygen species, the telluryl oxo (Te=O) is found to be the most nucleophilic. Whereas the adsorption of propane is weak regardless of the MO{sub x} species involved, isopropyl and H adsorption exhibits strong preference in the order of Te=O > V=O > bridging oxygens > empty Mo apical site, suggesting the importance of TeO{sub x} species for H abstraction. The adsorption energies of isopropyl and H and consequently the reaction energy of the initial dehydrogenation of propane are strongly dependent on the number of ab planes included in the cluster, which points to the need to employ multilayer cluster models to correctly capture the energetics of surface chemistry on this mixed metal oxide catalyst.

Govindasamy, Agalya [University of Cincinnati; Muthukumar, Kaliappan [University of Cincinnati; Yu, Junjun [University of Cincinnati; Xu, Ye [ORNL; Guliants, Vadim V. [University of Cincinnati

2010-01-01T23:59:59.000Z

412

Measurement of hard double-parton interactions in W(???) + 2-jet events at ?s=7 TeV with the ATLAS detector  

E-Print Network (OSTI)

The production of W bosons in association with two jets in protonproton collisions at a centre-of-mass energy of ?s=7 TeV has been analysed for the presence of double-parton interactions using data corresponding to an ...

Taylor, Frank E.

413

Phase diagram and magnetic structures of the Co-bearing dugganites Pb3TeCo3A2O14 (A = V, P)  

SciTech Connect

Exhibiting rich magnetic behaviour and potentially multiferroic properties, the dugganites, a Te^6+ containing subgroup of the langasite series, are an attractive family of compounds for future study. It was recently shown that Pb-bearing members of the dugganite series undergo distortions away from the P321 symmetry that is characteristic of the langasites. Here, we detail the consequences these distortions have on the magnetism exhibited by Pb3TeCo3V2O14 and Pb3TeCo3P2O14, solving the magnetic structures of both compounds with respect to a new supercell. Using neutron scattering and magnetic susceptibility measurements, we show that small applied magnetic fields can seriously perturb the delicate magnetic states in both of these systems. This is further demonstrated by presenting how doping P^5+ onto the nonmagnetic V^5+ site completely changes the magnetic structure from either of the end series members. Finally, it is shown using inelastic neutron scattering and magnetic susceptibility measurements that Pb3TeCo3V2O14 can be characterized using a model for isosceles trimers, which do not exist in the previously reported P321 subcell.

Silverstein, H.J. [University of Manitoda, Winnipeg, Canada; Sharma, A.Z. [University of Manitoda, Winnipeg, Canada; Stoller, A.J. [University of Manitoda, Winnipeg, Canada; Cruz-Kan, K. [University of Manitoda, Winnipeg, Canada; Flacau, Roxana [National Research Council of Canada; Donaberger, R. L. [National Research Council of Canada; Zhou, H. D. [Department of Physics and Astronomy, University of Tennessee; Manuel, P. [ISIS Facility, Rutherford Appleton Laboratory; Huq, Ashfia [ORNL; Kolesnikov, Alexander I [ORNL; Wiebe, Christopher [University of Winnipeg

2013-01-01T23:59:59.000Z

414

Supersymmetric discovery potential and benchmarks for early runs at {radical}(s)=7 TeV at the LHC  

Science Conference Proceedings (OSTI)

We carry out an analysis of the potential of the Large Hadron Collider (LHC) to discover supersymmetry in runs at {radical}(s)=7 TeV with an accumulated luminosity of (0.1-2) fb{sup -1} of data. The analysis is done with both minimal supergravity and supergravity models with nonuniversal soft breaking. Benchmarks for early discovery with (0.1-2) fb{sup -1} of data are given. We provide an update of b-tagging efficiencies in PGS 4 appropriate for LHC analyses. A large number of signature channels are analyzed, and it is shown that each of the models exhibited are discoverable at the 5{sigma} level or more above the standard model background in several signature channels which would provide cross checks for a discovery of supersymmetry. It is shown that some of the benchmarks are discoverable with 0.1 fb{sup -1} of data again with detectable signals in several channels.

Altunkaynak, Baris; Holmes, Michael; Nath, Pran; Nelson, Brent D.; Peim, Gregory [Department of Physics, Northeastern University, Boston, Massachusetts 02115 (United States)

2010-12-01T23:59:59.000Z

415

Appendix B: CArBon dioxide CApture teChnology SheetS R&D CollaboRations  

NLE Websites -- All DOE Office Websites (Extended Search)

R&D CollaboRations R&D CollaboRations B-556 R&D CollaboRations U.s. DepaRtment of eneRgy aDvanCeD CaRbon DioxiDe CaptURe R&D pRogRam: teChnology UpDate, may 2013 paRtneRship foR Co 2 CaptURe primary project goals The University of North Dakota Energy and Environmental Research Center (UNDEERC) is conducting pilot-scale testing to demonstrate and evaluate a range of carbon dioxide (CO 2 ) capture technologies to develop key technical and economic information that can be used to examine the feasibility of capture technologies as a function of fuel type and system configuration. technical goals * Integrate a high-efficiency flexible capture system with existing pilot-scale combustion

416

ORISE "AK RlDGE lNSTlT"TE FOR SCIENCE AND EDUCATION  

Office of Legacy Management (LM)

t\i,;;; il.,. (' t\i,;;; il.,. (' . d ORISE "AK RlDGE lNSTlT"TE FOR SCIENCE AND EDUCATION August 1,200l Robert Atkin U.S. Department of Energy Oak Ridge Operations Office P.O. Box 2001 Oak Ridge, TN 3783 1 SUBJECT: CONTRACT NO. DE-AC05000R22750 FINAL REPORT-VERIFICATION SURVEY OF THE NEW BRUNSWICK LABORATORY SITE, NEW BRUNSWICK, NEW JERSEY Dear Mr. Atkin: The Environmental Survey and Site Assessment Program (ESSAP) of the Oak Ridge Institute for Science and Education (ORISE) conducted verification surveys at the New Brunswick Laboratory Site, located in the town of New Brunswick, New Jersey, during the period of August through November 1996. A draft report detailing the procedures and results of the survey was submitted to the U.S. Department of Energy

417

Impact of Interface Recombination on Time Resolved Photoluminescence (TRPL) Decays in CdTe Solar Cells (Numerical Simulation Analysis): Preprint  

DOE Green Energy (OSTI)

Using Sentaurus Device Software, we analyze how bulk and interface recombination affect time-resolved photoluminescence (TRPL) decays in CdTe solar cells. This modeling analysis could improve the interpretation of TRPL data and increase the possibility of rapid defect characterization in thin-film solar cells. By illuminating the samples with photons of two different wavelengths, we try to deduce the spatial origin of the dominant recombination loss. Shorter-wavelength photons will be more affected by the interface recombination and drift compared to the longer ones. Using the two-wavelength TRPL characterization method, it may be possible to determine whether a specific change in deposition process has affected the properties of interface or the bulk of the absorber.

Kanevce, A.; Kuciauskas, D.; Gessert, T. A.; Levi, D. H.; Albin, D. S.

2012-06-01T23:59:59.000Z

418

Thermodynamic evaluation of the CdTe deposition by an elemental co-evaporation method under isothermal transport conditions  

SciTech Connect

Thermodynamic potential diagrams were used to predict the conditions for depositing cadmium telluride thin films from two independent elemental sources, Cd and Te, while keeping sources and substrate at the same temperature. The potential diagrams also allowed the evaluation of the influence of gaseous contaminants, such as oxygen, on the formed condensed phases. The method may be applied to the deposition of other compounds as long as their vapor pressures are much smaller than the vapor pressures of the constituent elements. The thermodynamic calculation suggested that the film may be deposited under total pressure of 10-4 mbar and at temperatures as low as 450 deg. C. This total pressure is easily achieved by a mechanical pump and the low temperature range allows the use of low cost glass substrates. The preliminary results showed that the films deposited under the conditions predicted by the thermodynamic calculations were uniform and crystalline, as confirmed by scanning electron microscopy and X-ray diffraction.

Ribeiro, M.C.R. [Pontificia Universidade Catolica do Rio de Janeiro, Departamento de Ciencia dos Materiais e Metalurgia, Rua Marques de Sao Vicente, 225 Gavea, 22453-900 Rio de Janeiro, RJ (Brazil)]. E-mail: mriccio@dcmm.puc-rio.br; Cruz, L.R. [Instituto Militar de Engenharia, Departamento de Engenharia Mecanica e de Materiais, Praca General Tiburcio, 80 Urca, 22290-270 Rio de Janeiro, RJ (Brazil); Avillez, R.R. de [Pontificia Universidade Catolica do Rio de Janeiro, Departamento de Ciencia dos Materiais e Metalurgia, Rua Marques de Sao Vicente, 225 Gavea, 22453-900 Rio de Janeiro, RJ (Brazil)

2006-01-05T23:59:59.000Z

419

Performance of a large TeO2 crystal as a cryogenic bolometer in searching for neutrinoless double beta decay  

E-Print Network (OSTI)

Bolometers are ideal devices in the search for neutrinoless Double Beta Decay. Enlarging the mass of individual detectors would simplify the construction of a large experiment, but would also decrease the background per unit mass induced by alpha-emitters located close to the surfaces and background arising from external and internal gamma's. We present the very promising results obtained with a 2.13 kg TeO2 crystal. This bolometer, cooled down to a temperature of 10.5 mK in a dilution refrigerator located deep underground in the Gran Sasso National Laboratories, represents the largest thermal detector ever operated. The detector exhibited an energy resolution spanning a range from 3.9 keV (at 145 keV) to 7.8 keV (at the 2615 gamma-line of 208Tl) FWHM. We discuss the decrease in the background per unit mass that can be achieved increasing the mass of a bolometer.

L. Cardani; L. Gironi; J. W. Beeman; I. Dafinei; Z. Ge; G. Pessina; S. Pirro; Y. Zhu

2011-06-03T23:59:59.000Z

420

Probing TeV Left-Right Seesaw at Energy and Intensity Frontiers: a Snowmass White Paper  

E-Print Network (OSTI)

We discuss ways to probe the origin of neutrino masses at the Energy and Intensity frontiers, in TeV-scale left-right seesaw models where small neutrino masses arise via type-I seesaw mechanism. We consider generic ('vanilla') version of such models as well as a version which leads to 'large' light-heavy neutrino mixing while keeping the neutrino masses small in a natural manner. We point out specific observable implications of these classes of models at the LHC as well as in searches for lepton flavor violating processes such as $\\mu\\to e\\gamma$ and $\\mu\\to 3e$, and also in searches for lepton number violating neutrinoless double beta decay.

P. S. Bhupal Dev; R. N. Mohapatra

2013-08-09T23:59:59.000Z

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421

Probing novel TeV physics through precision calculations of scalar and tensor charges of the nucleon  

E-Print Network (OSTI)

We present an update on the calculation of matrix elements of iso-vector scalar, axial and tensor charges between a neutron and a proton state. These matrix elements are needed to probe novel scalar and tensor interactions in neutron beta-decay that can arise in extensions of the Standard Model at the TeV scale. Our calculations are being done using valence clover fermions on dynamical N_f=2+1+1 HISQ configurations generated by the MILC Collaboration. We provide preliminary estimates of the dependence of these matrix elements on the light quark masses, lattice spacing, and the time separation between the source and sink of the nucleons. We also find that the renormalization constants calculated using the RI-sMOM scheme are close to unity for the HYP smeared HISQ lattices.

Rajan Gupta; Tanmoy Bhattacharya; Anosh Joseph; Saul D. Cohen; Huey-Wen Lin

2012-12-20T23:59:59.000Z

422

Performance of the ATLAS Tau and Missing Energy triggers with 7 TeV proton proton collisions at the LHC  

E-Print Network (OSTI)

A study of the performance of the ATLAS tau and missing energy triggers with data collected in spring 2010 at {\\surd}s = 7 TeV proton-proton collisions at the Large Hadron Collider (LHC) is presented. A comparison was performed between data and Monte Carlo simulations for the tau and missing transverse energy triggers. As well as a comparison between missing transverse energy trigger quantities and their offline reconstructed counterparts. Tau trigger results compare well with predictions from Monte Carlo simulations. Slight deviations are observed for tau shower shape quantities. Possible sources contributing to the discrepancy such as the simulation of the underlying event are currently being studied. The missing transverse energy reconstructed by the Event Filter is well correlated with the offline result. In addition, there is good agreement between the results obtained with collision data and Monte Carlo simulations.

Hooft van Huysduynen, L

2010-01-01T23:59:59.000Z

423

Performance of the ATLAS Tau and Missing Energy triggers with 7 TeV proton proton collisions at the LHC  

E-Print Network (OSTI)

A study of the performance of the ATLAS tau and missing energy triggers with data collected in spring 2010 at {\\surd}s = 7 TeV proton-proton collisions at the Large Hadron Collider (LHC) is presented. A comparison was performed between data and Monte Carlo simulations for the tau and missing transverse energy triggers. As well as a comparison between missing transverse energy trigger quantities and their offline reconstructed counterparts. Tau trigger results compare well with predictions from Monte Carlo simulations. Slight deviations are observed for tau shower shape quantities. Possible sources contributing to the discrepancy such as the simulation of the underlying event are currently being studied. The missing transverse energy reconstructed by the Event Filter is well correlated with the offline result. In addition, there is good agreement between the results obtained with collision data and Monte Carlo simulations.

L. Hooft van Huysduynen

2010-10-05T23:59:59.000Z

424

Search for Long-Lived Massive Charged Particles in 1.96 TeV $\\bar{p}p}$ Collisions  

E-Print Network (OSTI)

We performed a signature-based search for long-lived charged massive particles (CHAMPs) produced in 1.0 $\\rm{fb}^{-1}$ of $\\bar{p}p$ collisions at $\\sqrt{s}=1.96$ TeV, collected with the CDF II detector using a high transverse-momentum ($p_T$) muon trigger. The search used time-of-flight to isolate slowly moving, high-$p_T$ particles. One event passed our selection cuts with an expected background of $1.9 \\pm 0.2$ events. We set an upper bound on the production cross section, and, interpreting this result within the context of a stable scalar top quark model, set a lower limit on the particle mass of 249 GeV/$c^2$ at 95% C.L.

CDF Collaboration; T. Aaltonen

2009-02-07T23:59:59.000Z

425

Impact of Interface Recombination on Time Resolved Photoluminescence Decays (TRPL) in CdTe Solar Cells (Numerical Simulation Analysis) (Poster)  

DOE Green Energy (OSTI)

Using Sentaurus Device Software, we analyze how bulk and interface recombination affect time-resolved photoluminescence (TRPL) decays in CdTe solar cells. This modeling analysis could improve the interpretation of TRPL data and increase the possibility of rapid defect characterization in thin-film solar cells. By illuminating the samples with photons of two different wavelengths, we try to deduce the spatial origin of the dominant recombination loss. Shorter-wavelength photons will be more affected by the interface recombination and drift compared to the longer ones. Using the two-wavelength TRPL characterization method, it may be possible to determine whether a specific change in deposition process has affected the properties of interface or the bulk of the absorber.

Kanevce, A.; Kuciauskas, D.; Gessert, T. A.; Levi, D. H.; Albin, D. S.

2012-06-01T23:59:59.000Z

426

An effect of the networks of the subgrain boundaries on spectral responses of thick CdZnTe detectors  

Science Conference Proceedings (OSTI)

CdZnTe (CZT) crystals used for nuclear-radiation detectors often contain high concentrations of subgrain boundaries and networks of poligonized dislocations that can significantly degrade the performance of semiconductor devices. These defects exist in all commercial CZT materials, regardless of their growth techniques and their vendor. We describe our new results from examining such detectors using IR transmission microscopy and white X-ray beam diffraction topography. We emphasize the roles on the devices performances of networks of subgrain boundaries with low dislocation densities, such as poligonized dislocations and mosaic structures. Specifically, we evaluated their effects on the gamma-ray responses of thick, >10 mm, CZT detectors. Our findings set the lower limit on the energy resolution of CZT detectors containing dense networks of subgrain boundaries, and walls of dislocations.

Bolotnikov, A.; Butcher, J.; Camarda, G.; Cui, Y.; Egarievwe, S.; Fochuk, P.; Gul,R.; Hamade, M.; Hossain, A.; Kim, K.; Kopach,O.; Petryk, M.; Raghothamachar, B.; Yang, G.; and James, R.B.

2011-08-12T23:59:59.000Z

427

Probing TeV scale physics via ultra cold neutron decays and calculating non-standard baryon matrix elements  

E-Print Network (OSTI)

We motivate undertaking precision analyses of neutron decays to look for signatures of new scalar and tensor interactions that can arise in extensions of the Standard Model at the TeV scale. The key ingrediant needed to connect experimental data with theoretical analysis are high-precision calculations of matrix elements of isovector bilinear operators between the decaying neutron and final state proton. We describe the status of our Lattice QCD program of using valence clover fermions on dynamical N_f=2+1+1 HISQ configurations generated by the MILC Collaboration. On the theoretical side we use the effective field theory method and provide both model independent and dependent analyses to obtain bounds on possible scalar and tensor interactions, both from low energy experiments and LHC data.

Rajan Gupta; Tanmoy Bhattacharya; Anosh Joseph; Huey-Wen Lin; Saul D. Cohen

2012-02-07T23:59:59.000Z

428

Reversible tuning of the surface state in a pseudobinary Bi2(Te-Se)3 topological insulator  

SciTech Connect

We use angle-resolved photoemission spectroscopy to study a nontrivial surface state in a pseudobinary Bi2Te2.8Se0.2 topological insulator. We show that, unlike previously studied binaries, this is an intrinsic topological insulator with the conduction bulk band residing well above the chemical potential. Our data indicate that under a good vacuum condition there are no significant aging effects for more than two weeks after cleaving. We also demonstrate that the shift of the Kramers point at low temperature is caused by UV-assisted absorption of molecular hydrogen. Our findings pave the way for applications of these materials in devices and present an easy scheme to tune their properties.

Jiang, Rui; Wang, Lin-Lin; Huang, Mianliang; Dhaka, Rajendra S.; Johnson, Duane D.; Lograsso, Thomas A.; Kaminski, Adam

2012-08-10T23:59:59.000Z

429

Specific features of conductivity of {gamma}-irradiated TlGaTe{sub 2} crystals with nanochain structure  

Science Conference Proceedings (OSTI)

Temperature dependences of electrical conductivity {sigma}(T) and current-voltage characteristics of one-dimensional TlGaTe{sub 2} single crystals subjected to various doses of {gamma}-ray radiation in both geometries of the experiment-along nanochains parallel to the tetragonal axis of the crystal ({sigma}{sub |} ) and perpendicular to these nanochains ({sigma}{sub perpendicular} )-are studied. It is shown that the dependence {sigma}(T) measured in the ohmic region of the current-voltage characteristic is the shape typical of the hopping mechanism and can be described in terms of the Mott approximation. The values of the densities of localized states N{sub F}, the activation energy E{sub a}, the hop lengths R, the difference between the energies of states {Delta}E in the vicinity of the Fermi level, and the concentrations of deep traps N{sub t} are determined. The current-voltage characteristics in the region of a more abrupt increase in the current are also studied. It is shown that this region of current-voltage characteristics is described in the context of the Pool-Frenkel thermal-field effect. Concentrations of ionized centers N{sub f}, the free-path lengths {lambda}, the Frenkel coefficients {beta}, and the shape of the potential well in initial and irradiated (with 250 Mrad) TlGaTe{sub 2} crystals are determined. It is shown that anisotropy of electrical conductivity changes under the effect of irradiation, which brings about translational ordering of nanochains.

Sardarli, R. M., E-mail: sardarli@yahoo.com; Samedov, O. A.; Abdullayev, A. P. [National Academy of Sciences of Azerbaijan, Institute of Radiation Problems (Azerbaijan); Huseynov, E. K. [National Academy of Sciences of Azerbaijan, Institute of Physics (Azerbaijan); Salmanov, F. T.; Safarova, G. R. [National Academy of Sciences of Azerbaijan, Institute of Radiation Problems (Azerbaijan)

2010-05-15T23:59:59.000Z

430

Detection of THz radiation with devices made from wafers with HgTe and InSb quantum wells  

SciTech Connect

In this study we present measurements of the Terahertz (THz) photoconductivity of 2D electron system realized at HgTe/HgCdTe and AlInSb/InSb/AlInSb quantum wells (QWs) in Corbino geometry (inner and outer radius: 500 {mu}m and 1500 {mu}m) with different mobilities and electron densities. To characterize the devices, the Shubnikov-de Haas (SdH) effect up to magnetic fields B of 7T and current-voltage (I-V) characteristics at various magnetic fields were measured. The THz radiation is provided by a p-Ge laser which operates with a magnetic field and a high voltage for the electrical pumping. The stimulated emission is caused by transitions between Landau levels of light holes [1]. The laser is tunable in the range between 1.7 to 2.5 THz (corresponding to wavelengths between 120 to 180 {mu}m or energies of 7 to 12 meV). The laser is pulsed with a pulse rate of 1 Hz and pulse lengths of about 1 {mu}s with low switching times (about 20 ns). The monochromatic THz radiation is transferred to our samples via a 0.32m long brass waveguide immersed in liquid Helium. The detection of a change in the conductivity of the sample due to absorption of THz-radiation (photoresponse) requires a low-noise circuit. For the Corbino-shaped samples the photoresponse (PR) is measured via a resistor R{sub V} of 1 k{Omega}. The signal is transferred via in a high-frequency cable and detected with a digital oscilloscope.

Gouider, F.; Nachtwei, G. [Institut fuer Angewandte Physik, Technische Universitaet Braunschweig, D-38106 Braunschweig (Germany); Vasilyev, Yu. B.; Koenemann, J. [A. F. Ioffe Physical Technical Institute, RU-194021 St. Petersburg (Russian Federation); Buckle, P. D. [QinetiQ Ltd, Malvern WR14 3PS (United Kingdom); Bruene, C.; Buhmann, H. [Julius-Maximilians-University Wuerzburg, D-97074 (Germany)

2011-12-23T23:59:59.000Z

431

Simulation, Modeling, and Crystal Growth of Cd0.9Zn0.1Te for Nuclear Spectrometers  

Science Conference Proceedings (OSTI)

High-quality, large (10 cm long and 2.5 cm diameter), nuclear spectrometer grade Cd{sub 0.9}Zn{sub 0.1}Te (CZT) single crystals have been grown by a controlled vertical Bridgman technique using in-house zone refined precursor materials (Cd, Zn, and Te). A state-of-the-art computer model, multizone adaptive scheme for transport and phase-change processes (MASTRAP), is used to model heat and mass transfer in the Bridgman growth system and to predict the stress distribution in the as-grown CZT crystal and optimize the thermal profile. The model accounts for heat transfer in the multiphase system, convection in the melt, and interface dynamics. The grown semi-insulating (SI) CZT crystals have demonstrated promising results for high-resolution room-temperature radiation detectors due to their high dark resistivity ({rho} {approx} 2.8 x 10{sup 11} {Theta} cm), good charge-transport properties, electron and hole mobility-life-time product, {mu}{tau}{sub e} {approx} (2-5) x 10{sup -3} and {mu}{tau}{sub h} {approx} (3-5) x 10{sup -5} respectively, and low cost of production. Spectroscopic ellipsometry and optical transmission measurements were carried out on the grown CZT crystals using two-modulator generalized ellipsometry (2-MGE). The refractive index n and extinction coefficient k were determined by mathematically eliminating the {approx}3-nm surface roughness layer. Nuclear detection measurements on the single-element CZT detectors with {sup 241}Am and {sup 137}Cs clearly detected 59.6 and 662 keV energies with energy resolution (FWHM) of 2.4 keV (4.0%) and 9.2 keV (1.4%), respectively.

Mandal, Krishna [EIC Laboratories, Inc.; Kang, Sung Hoon [EIC Laboratories, Inc.; Choi, Michael [EIC Laboratories, Inc.; Bello, Job [EIC Laboratories, Inc.; Zheng, Lili [State University of New York, Stony Brook; Zhang, Hui [State University of New York, Stony Brook; Groza, Michael [Fisk University, Nashville, TN; Roy, Utpal N. [Fisk University, Nashville, TN; Burger, Arnold [Fisk University, Nashville, TN; Jellison Jr, Gerald Earle [ORNL; Holcomb, David Eugene [ORNL; Wright, Gomez W [ORNL; Williams, Joseph A [ORNL

2006-01-01T23:59:59.000Z

432

NREL Determines Long-Lived Carriers and Differences in CdTe Superstrate and Substrate Cells (Fact Sheet)  

DOE Green Energy (OSTI)

NREL study may provide future guidance in improving CdS/CdTe photovoltaic device performance. The majority of minority carrier lifetime (MCL) studies performed on CdS/CdTe photovoltaic (PV) devices have correlated device performance primarily with the fast decay observed in time-resolved photoluminescence (TRPL) measurements (t{sub 1}). This decay is believed to be associated primarily with recombination in depletion width (W{sub D}), and therefore should be a good indicator of device quality if carrier generation occurs primarily within WD. However, although previous studies have shown that t1 can be a good indicator of broad device quality, it does not correlate as well with small changes in device performance and/or with differences observed between superstrate and substrate devices. Researchers at the National Renewable Energy Laboratory (NREL) have shown that in this case, the parameter t{sub 2} (from the longer-term decay of TRPL) may not only provide a better correlation with device open-circuit voltage (V{sub OC}) for superstrate devices but may also provide guidance for inter-comparison with alternative device designs (e.g., substrate devices). It is also suggested that previous studies may yield added value if a larger number of TRPL parameters (i.e., t{sub 1}, t{sub 2}, and respective amplitudes) are re-examined as a function of device performance. The parameter t{sub 2} may not only provide a better correlation with device VOC for superstrate devices but may also provide guidance for inter-comparison with alternative device designs (e.g., substrate devices).

Not Available

2012-02-01T23:59:59.000Z

433

Search for Supersymmetry Using Final States with One Lepton, Jets, and Missing Transverse Momentum with the ATLAS Detector in ?s=7??[square root of s=7] TeV pp Collisions  

E-Print Network (OSTI)

This Letter presents the first search for supersymmetry in final states containing one isolated electron or muon, jets, and missing transverse momentum from ?s=7??[square root of s=7] TeV proton-proton collisions at the ...

Taylor, Frank E.

434

Study of minimum-bias-trigger events at \\Sqrt s = 0.2-0.9 TeV with magnetic and calorimetric analysis at the CERN proton-antiproton collider  

E-Print Network (OSTI)

Study of minimum-bias-trigger events at \\Sqrt s = 0.2-0.9 TeV with magnetic and calorimetric analysis at the CERN proton-antiproton collider

Ceradini, F

1985-01-01T23:59:59.000Z

435

Development of a computer model for polycrystalline thin-film CuInSe{sub 2} and CdTe solar cells. Annual subcontract report, 1 January 1990--31 December 1990  

DOE Green Energy (OSTI)

This report describes work to develop a highly accurate numerical model for CuInSe{sub 2} and CdTe solar cells. ADEPT (A Device Emulation Program and Toolbox), a one-dimensional semiconductor device simulation code developed at Purdue University, was used as the basis of this model. An additional objective was to use ADEPT to analyze the performance of existing and proposed CuInSe{sub 2} and CdTe solar cell structures. The work is being performed in two phases. The first phase involved collecting device performance parameters, cell structure information, and material parameters. This information was used to construct the basic models to simulate CuInSe{sub 2} and CdTe solar cells. This report is a tabulation of information gathered during the first phase of this project on the performance of existing CuInSe{sub 2} and CdTe solar cells, the material properties of CuInSr{sub 2}, CdTe, and CdS, and the optical absorption properties of CuInSe{sub 2}, CdTe, and CdS. The second phase will entail further development and the release of a version of ADEPT tailored to CuInSe{sub 2} and CdTe solar cells that can be run on a personal computer. In addition, ADEPT will be used to analyze the performance of existing and proposed CuInSe{sub 2} and CdTe solar cell structures. 110 refs.

Gray, J.L.; Schwartz, R.J.; Lee, Y.J. [Purdue Univ., Lafayette, IN (United States)

1992-04-01T23:59:59.000Z

436

Measurement of the atmospheric neutrino energy spectrum from 100 GeV to 400 TeV with IceCube  

E-Print Network (OSTI)

A measurement of the atmospheric muon neutrino energy spectrum from 100 GeV to 400 TeV was performed using a data sample of about 18,000 up-going atmospheric muon neutrino events in IceCube. Boosted decision trees were used for event selection to reject mis-reconstructed atmospheric muons and obtain a sample of up-going muon neutrino events. Background contamination in the final event sample is less than one percent. This is the first measurement of atmospheric neutrinos up to 400 TeV, and is fundamental to understanding the impact of this neutrino background on astrophysical neutrino observations with IceCube. The measured spectrum is consistent with predictions for the atmospheric muon neutrino plus muon antineutrino flux.

IceCube Collaboration; R. Abbasi; Y. Abdou; T. Abu-Zayyad; J. Adams; J. A. Aguilar; M. Ahlers; K. Andeen; J. Auffenberg; X. Bai; M. Baker; S. W. Barwick; R. Bay; J. L. Bazo Alba; K. Beattie; J. J. Beatty; S. Bechet; J. K. Becker; K. -H. Becker; M. L. Benabderrahmane; S. BenZvi; J. Berdermann; P. Berghaus; D. Berley; E. Bernardini; D. Bertrand; D. Z. Besson; M. Bissok; E. Blaufuss; J. Blumenthal; D. J. Boersma; C. Bohm; D. Bose; S. Bser; O. Botner; J. Braun; S. Buitink; M. Carson; D. Chirkin; B. Christy; J. Clem; F. Clevermann; S. Cohen; C. Colnard; D. F. Cowen; M. V. D'Agostino; M. Danninger; J. C. Davis; C. De Clercq; L. Demirrs; O. Depaepe; F. Descamps; P. Desiati; G. de Vries-Uiterweerd; T. DeYoung; J. C. Daz-Vlez; M. Dierckxsens; J. Dreyer; J. P. Dumm; M. R. Duvoort; R. Ehrlich; J. Eisch; R. W. Ellsworth; O. Engdegrd; S. Euler; P. A. Evenson; O. Fadiran; A. R. Fazely; A. Fedynitch; T. Feusels; K. Filimonov; C. Finley; M. M. Foerster; B. D. Fox; A. Franckowiak; R. Franke; T. K. Gaisser; J. Gallagher; M. Geisler; L. Gerhardt; L. Gladstone; T. Glsenkamp; A. Goldschmidt; J. A. Goodman; D. Grant; T. Griesel; A. Gro; S. Grullon; M. Gurtner; C. Ha; A. Hallgren; F. Halzen; K. Han; K. Hanson; K. Helbing; P. Herquet; S. Hickford; G. C. Hill; K. D. Hoffman; A. Homeier; K. Hoshina; D. Hubert; W. Huelsnitz; J. -P. Hl; P. O. Hulth; K. Hultqvist; S. Hussain; A. Ishihara; J. Jacobsen; G. S. Japaridze; H. Johansson; J. M. Joseph; K. -H. Kampert; T. Karg; A. Karle; J. L. Kelley; N. Kemming; P. Kenny; J. Kiryluk; F. Kislat; S. R. Klein; J. -H. Khne; G. Kohnen; H. Kolanoski; L. Kpke; D. J. Koskinen; M. Kowalski; T. Kowarik; M. Krasberg; T. Krings; G. Kroll; K. Kuehn; T. Kuwabara; M. Labare; S. Lafebre; K. Laihem; H. Landsman; M. J. Larson; R. Lauer; R. Lehmann; J. Lnemann; J. Madsen; P. Majumdar; A. Marotta; R. Maruyama; K. Mase; H. S. Matis; M. Matusik; K. Meagher; M. Merck; P. Mszros; T. Meures; E. Middell; N. Milke; J. Miller; T. Montaruli; A. R. Morse; S. M. Movit; R. Nahnhauer; J. W. Nam; U. Naumann; P. Nieen; D. R. Nygren; S. Odrowski; A. Olivas; M. Olivo; A. O'Murchadha; M. Ono; S. Panknin; L. Paul; C. Prez de los Heros; J. Petrovic; A. Piegsa; D. Pieloth; R. Porrata; J. Posselt; P. B. Price; M. Prikockis; G. T. Przybylski; K. Rawlins; P. Redl; E. Resconi; W. Rhode; M. Ribordy; A. Rizzo; J. P. Rodrigues; P. Roth; F. Rothmaier; C. Rott; T. Ruhe; D. Rutledge; B. Ruzybayev; D. Ryckbosch; H. -G. Sander; M. Santander; S. Sarkar; K. Schatto; S. Schlenstedt; T. Schmidt; A. Schukraft; A. Schultes; O. Schulz; M. Schunck; D. Seckel; B. Semburg; S. H. Seo; Y. Sestayo; S. Seunarine; A. Silvestri; K. Singh; A. Slipak; G. M. Spiczak; C. Spiering; M. Stamatikos; B. T. Stanev; G. Stephens; T. Stezelberger; R. G. Stokstad; S. Stoyanov; E. A. Strahler; T. Straszheim; G. W. Sullivan; Q. Swillens; H. Taavola; I. Taboada; A. Tamburro; O. Tarasova; A. Tepe; S. Ter-Antonyan; S. Tilav; P. A. Toale; S. Toscano; D. Tosi; D. Tur?an; N. van Eijndhoven; J. Vandenbroucke; A. Van Overloop; J. van Santen; M. Voge; B. Voigt; C. Walck; T. Waldenmaier; M. Wallraff; M. Walter; Ch. Weaver; C. Wendt; S. Westerhoff; N. Whitehorn; K. Wiebe; C. H. Wiebusch; G. Wikstrm; D. R. Williams; R. Wischnewski; H. Wissing; M. Wolf; K. Woschnagg; C. Xu; X. W. Xu; G. Yodh; S. Yoshida; P. Zarzhitsky

2010-10-19T23:59:59.000Z

437

Gamma Ray Burst Section of the White Paper on the Status and Future of Ground-based TeV Gamma-ray Astronomy  

E-Print Network (OSTI)

This is a report on the findings of the gamma ray burst working group for the white paper on the status and future of TeV gamma-ray astronomy. The white paper is an APS commissioned document, and the overall version has also been released and can be found on astro-ph. This detailed section of the white paper discusses the status of past and current attempts to observe gamma ray bursts at GeV-TeV energies. We concentrate on the potential of future ground-based gamma-ray experiments to observe the highest energy emission ever recorded for GRBs, particularly for those that are nearby and have high Lorentz factors in the GRB jet. It is clear that major advances are possible and that the detection of very high energy emission would have strong implications for GRB models, as well as cosmic ray origin.

A. D. Falcone; D. A. Williams; M. G. Baring; R. Blandford; J. Buckley; V. Connaughton; P. Coppi; C. Dermer; B. Dingus; C. Fryer; N. Gehrels; J. Granot; D. Horan; J. I. Katz; K. Kuehn; P. Meszaros; J. Norris; P. Saz Parkinson; A. Pe'er; E. Ramirez-Ruiz; S. Razzaque; X. Y. Wang; B. Zhang

2008-10-02T23:59:59.000Z

438