National Library of Energy BETA

Sample records for uup se te

  1. New Rate Schedule CV-UUP1 UNITED STATES DEPARTMENT OF ENERGY

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and dispatch service needed to support the transmission service. Penalty Rate: The formula rate for Unreserved Use Penalty (UUP) has three components. Component 1: The UUP...

  2. Magneto-optical characterizations of FeTe???Se??? thin...

    Office of Scientific and Technical Information (OSTI)

    in the two thin films. Compared with bulk crystals, FeTeSe thin film demonstrates not only higher Tc, but also much larger Jc, which is attractive for...

  3. Synthesis and structural characterization of ZnTe/ZnSe core/shell tunable quantum dots

    E-Print Network [OSTI]

    Guan, Juan

    2008-01-01

    Colloidal semiconductor nanocrystals or quantum dots have attracted much attention recently with their unique optical properties. Here we present a novel approach to synthesize ZnTe/ZnSe core/shell tunable quantum dots. ...

  4. Role of polycrystallinity in CdTe and CuInSe sub 2 photovoltaic cells

    SciTech Connect (OSTI)

    Sites, J.R. )

    1991-01-01

    The polycrystalline nature of thin-film CdTe and CuInSe{sub 2} solar cells continues to be a major factor in several individual losses that limit overall cell efficiency. This report describes progress in the quantitative separation of these losses, including both measurement and analysis procedures. It also applies these techniques to several individual cells to help document the overall progress with CdTe and CuInSe{sub 2} cells. Notably, CdTe cells from Photon Energy have reduced window photocurrent losses to 1 mA/Cm{sup 2}; those from the University of South Florida have achieved a maximum power voltage of 693 mV; and CuInSe{sub 2} cells from International Solar Electric Technology have shown a hole density as high as 7 {times} 10{sup 16} cm{sup {minus}3}, implying a significant reduction in compensation. 9 refs.

  5. Hydrogen passivation of Se and Te in AlSb M. D. McCluskey and E. E. Haller

    E-Print Network [OSTI]

    McCluskey, Matthew

    Hydrogen passivation of Se and Te in AlSb M. D. McCluskey and E. E. Haller Lawrence Berkeley observed local vibrational modes LVM's arising from DX-hydrogen complex in AlSb. Hydrogen was diffused into bulk AlSb:Se and AlSb:Te by annealing in sealed quartz ampoules with either hydrogen gas or methanol CH

  6. Nanoscale chemical phase separation in FeTe0.55Se0.45 as seen...

    Office of Scientific and Technical Information (OSTI)

    DOE PAGES Search Results Publisher's Accepted Manuscript: Nanoscale chemical phase separation in FeTe0.55Se0.45 as seen via scanning tunneling spectroscopy Prev Next Title:...

  7. DETERMINATION OF BACK CONTACT BARRIER HEIGHT IN Cu(In,Ga)(Se,S)2 AND CdTe SOLAR CELLS

    E-Print Network [OSTI]

    Sites, James R.

    DETERMINATION OF BACK CONTACT BARRIER HEIGHT IN Cu(In,Ga)(Se,S)2 AND CdTe SOLAR CELLS Galymzhan T-contact metallization. The input data is the current- voltage (J-V) curves for the solar cell measured over a range point technique and apply it to specific solar-cell examples. The range of Jt that can be practically

  8. Magneto-optical characterizations of FeTe???Se??? thin films with critical current density over 1 MA/cm²

    SciTech Connect (OSTI)

    Sun, Yue; Li, Qiang; Tsuchiya, Yuji; Pyon, Sunseng; Tamegai, Tsuyoshi; Zhang, Cheng; Ozaki, Toshinori

    2015-01-01

    We performed magneto-optical (MO) measurements on FeTe???Se??? thin films grown on LaAlO? (LAO) and Yttria-stabilized zirconia (YSZ) single-crystalline substrates. These thin films show superconducting transition temperature Tc ~19 K, 4 K higher than the bulk sample. Typical roof-top patterns can be observed in the MO images of thin films grown on LAO and YSZ, from which a large and homogeneous critical current density Jc ~ 3 - 4 x 10? A/cm² at 5 K was obtained. Magnetic flux penetration measurement reveals that the current is almost isotropically distributed in the two thin films. Compared with bulk crystals, FeTe???Se??? thin film demonstrates not only higher Tc, but also much larger Jc, which is attractive for applications.

  9. SPECTROSCOPIC INVESTIGATION OF (NH4)2S TREATED GaSeTe FOR RADIATION DETECTOR APPLICATIONS

    SciTech Connect (OSTI)

    Nelson, A; Laurence, T; Conway, A; Behymer, E; Sturm, B; Voss, L; Nikolic, R; Payne, S; Mertiri, A; Pabst, G; Mandal, K; Burger, A

    2009-08-04

    The surface of the layered III-VI chalcogenide semiconductor GaSeTe was treated with (NH{sub 4}){sub 2}S at 60 C to modify the surface chemistry and determine the effect on transport properties. Room temperature photoluminescence (PL) measurements were used to assess the effect of the (NH{sub 4}){sub 2}S treatment on surface defect states. Evaluation of the subsequent surface chemistry was performed with high-resolution core-level photoemission measurements. Metal overlayers were deposited on the (NH{sub 4}){sub 2}S treated surfaces and the I-V characteristics were measured. The measurements were correlated to understand the effect of (NH{sub 4}){sub 2}S modification of the interfacial electronic structure with the goal of optimizing the metal/GaSeTe interface for radiation detector devices.

  10. Magneto-optical characterizations of FeTe???Se??? thin films with critical current density over 1 MA/cm²

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sun, Yue; Li, Qiang; Tsuchiya, Yuji; Pyon, Sunseng; Tamegai, Tsuyoshi; Zhang, Cheng; Ozaki, Toshinori

    2014-12-03

    We performed magneto-optical (MO) measurements on FeTe???Se??? thin films grown on LaAlO? (LAO) and Yttria-stabilized zirconia (YSZ) single-crystalline substrates. These thin films show superconducting transition temperature Tc ~19 K, 4 K higher than the bulk sample. Typical roof-top patterns can be observed in the MO images of thin films grown on LAO and YSZ, from which a large and homogeneous critical current density Jc ~ 3 - 4 x 10? A/cm² at 5 K was obtained. In this study, magnetic flux penetration measurement reveals that the current is almost isotropically distributed in the two thin films. Compared with bulk crystals,more »FeTe???Se??? thin film demonstrates not only higher Tc, but also much larger Jc, which is attractive for applications.« less

  11. Observation of an electron band above the Fermi level in FeTe?.??Se?.?? from in-situ surface doping

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, P.; Richard, P.; Xu, N.; Xu, Y. -M.; Ma, J.; Qian, T.; Fedorov, A. V.; Denlinger, J. D.; Gu, G. D.; Ding, H.

    2014-10-27

    We used in-situ potassium (K) evaporation to dope the surface of the iron-based superconductor FeTe?.??Se?.??. The systematic study of the bands near the Fermi level confirms that electrons are doped into the system, allowing us to tune the Fermi level of this material and to access otherwise unoccupied electronic states. In particular, we observe an electron band located above the Fermi level before doping that shares similarities with a small three-dimensional pocket observed in the cousin, heavily-electron-doped KFe??xSe? compound.

  12. Nanoscale chemical phase separation in FeTe0.55Se0.45 as seen via scanning tunneling spectroscopy

    SciTech Connect (OSTI)

    He, Xiaobo [Louisiana State University; Li, Guorong [Louisiana State University; Zhang, Jiandi [Louisiana State University; Karki, A B [Louisiana State University; Jin, Rongying [Louisiana State University; Sales, Brian C [ORNL; Safa-Sefat, Athena [ORNL; McGuire, Michael A [ORNL; Mandrus, David [ORNL; Plummer, E. W. [Louisiana State University

    2011-01-01

    Atomically resolved structural and electronic properties of FeTe{sub 1-x}Se{sub x} (x = 0 and 0.45) have been studied with scanning tunneling microscopy/spectroscopy (STM/STS). In contrast to the extreme flatness of the Te-terminated FeTe surface, nanoscale chemical phase separation between Te and Se atoms is unambiguously revealed on the surface of FeTe{sub 0.55}Se{sub 0.45}. A statistical counting of the two kinds of atoms has the same ratio as that in the bulk. Remarkably, there is no electronic phase separation seen in the tunneling spectroscopy. This indicates that the optimally doped superconductor is chemically inhomogeneous but electronically homogeneous, in contrast to many correlated electron materials.

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

    SciTech Connect (OSTI)

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

    1994-08-01

    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.

  14. Polytypism, polymorphism, and superconductivity in TaSe2–xTex

    SciTech Connect (OSTI)

    Luo, Huixia; Xie, Weiwei; Tao, Jing; Inoue, Hiroyuki; Gyenis, András; Krizan, Jason W.; Yazdani, Ali; Zhu, Yimei; Cava, Robert Joseph

    2015-03-03

    Polymorphism in materials often leads to significantly different physical properties - the rutile and anatase polymorphs of TiO? are a prime example. Polytypism is a special type of polymorphism, occurring in layered materials when the geometry of a repeating structural layer is maintained but the layer stacking sequence of the overall crystal structure can be varied; SiC is an example of a material with many polytypes. Although polymorphs can have radically different physical properties, it is much rarer for polytypism to impact physical properties in a dramatic fashion. Here we study the effects of polytypism and polymorphism on the superconductivity of TaSe?, one of the archetypal members of the large family of layered dichalcogenides. We show that it is possible to access 2 stable polytypes and 2 stable polymorphs in the TaSe2-xTex solid solution, and find that the 3R polytype shows a superconducting transition temperature that is between 6 and 17 times higher than that of the much more commonly found 2H polytype. Thus, the reason for this dramatic change is not apparent, but we propose that it arises either from a remarkable dependence of Tc on subtle differences in the characteristics of the single layers present, or from a surprising effect of the layer stacking sequence on electronic properties that instead are expected to be dominated by the properties of a single layer in materials of this kind.

  15. Structural, electrical and optical properties of Bi{sub 2}Se{sub 3} and Bi{sub 2}Se{sub (3-x)}Te {sub x} thin films

    SciTech Connect (OSTI)

    Augustine, Saji [Crystal Growth Laboratory, Department of Physics, Cochin University of Science and Technology, Cochin 682022, Kerala, (India) and Materials and Process Simulation Laboratory, Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305701 (Korea, Republic of)]. E-mail: sajia@kaist.ac.kr; Ampili, S. [Crystal Growth Laboratory, Department of Physics, Cochin University of Science and Technology, Cochin 682022, Kerala (India); Kang, Jeung Ku [Materials and Process Simulation Laboratory, Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305701 (Korea, Republic of); Mathai, Elizabeth [Crystal Growth Laboratory, Department of Physics, Cochin University of Science and Technology, Cochin 682022, Kerala (India)

    2005-08-11

    Thin films of Bi{sub 2}Se{sub 3}, Bi{sub 2}Se{sub 2.9}Te{sub 0.1}, Bi{sub 2}Se{sub 2.7}Te{sub 0.3} and Bi{sub 2}Se{sub 2.6}Te{sub 0.4} are prepared by compound evaporation. Micro structural, optical and electrical measurements are carried out on these films. X-ray diffraction pattern indicates that the as-prepared films are polycrystalline in nature with exact matching of standard pattern. The composition and morphology are determined using energy dispersive X-ray analysis and scanning electron microscopy (SEM). The optical band gap, which is direct allowed, is 0.67 eV for Bi{sub 2}Se{sub 3} thin films and the activation energy is 53 meV. Tellurium doped thin films also show strong optical absorption corresponding to a band gap of 0.70-0.78 eV. Absolute value of electrical conductivity in the case of tellurium doped thin film shows a decreasing trend with respect to parent structure.

  16. Structural and dynamical properties of Bridgman-grown CdSe[subscript x]Te[subscript 1?x] (0

    E-Print Network [OSTI]

    Talwar, Devki N.

    Measurements of the Raman scattering and extended x-ray-absorption fine-structure (EXAFS) spectroscopy are reported on a series of Bridgman-grown zinc-blende CdTe[subscript 1?x]Se[subscript x] (0.35 ? x > 0.05) ternary ...

  17. Interface Driven Energy Filtering of Thermoelectric Power in Spark Plasma Sintered Bi2Te2.7Se0.3 Nanoplatelet Composites

    E-Print Network [OSTI]

    Xiong, Qihua

    -ray diffraction, transmission electron microscopy, thermoelectric, and thermal transport measurements illustrateInterface Driven Energy Filtering of Thermoelectric Power in Spark Plasma Sintered Bi2Te2.7Se0 that the pellet sintered at 250 °C shows a minimum grain growth and an optimal number of interfaces for efficient

  18. Thermal studies of Se{sub 85-x}Te{sub 15}In{sub x} (x = 3,6,9,12) glasses

    SciTech Connect (OSTI)

    Sushama, D. [Dept. of Physics, MSM College, Kayamkulam, Kerala (India); George, Achamma [Dept. of Physics, St. Stephans' College, Pathanapuram, Kerala (India); Asokan, S. [Dept. of Instrumentation, Indian Institute of Science, Bangalore (India)

    2011-10-20

    Bulk glasses of compositions Se{sub 85-x}Te{sub 15}In{sub x} (x = 3,6,9,12) are prepared by melt quenching technique and Differential scanning calorimetry (DSC) is employed to study the thermal stability, crystallization mechanism as well as specific heat of these glasses. It is found that the addition of indium increases the glass transition temperature. From the heating rate dependence of the glass transition temperature the activation energy of glass transition is determined using Kissinger's equation for non-isothermal crystallization of materials. An attempt has been made to explain the variation in the value of T{sub c}, T{sub p} and {Delta}C{sub p} for the composition Se{sub 73}Te{sub 15}In{sub 12} using rigidity percolation threshold (RPT). From the values of (T{sub c}-T{sub g}) the stable glass system is determined.

  19. The role of stoichiometric vacancy periodicity in pressure-induced amorphization of the Ga{sub 2}SeTe{sub 2} semiconductor alloy

    SciTech Connect (OSTI)

    Abdul-Jabbar, N. M. [Department of Nuclear Engineering, University of California, Berkeley, California 94720 (United States); Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Kalkan, B.; MacDowell, A. A. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Huang, G.-Y. [Department of Nuclear Engineering, University of Tennessee, Knoxville, Tennessee 37996 (United States); Gronsky, R. [Department of Materials Science and Engineering, University of California, Berkeley, California 94720 (United States); Bourret-Courchesne, E. D. [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Wirth, B. D. [Department of Nuclear Engineering, University of California, Berkeley, California 94720 (United States); Department of Nuclear Engineering, University of Tennessee, Knoxville, Tennessee 37996 (United States)

    2014-08-04

    We observe that pressure-induced amorphization of Ga{sub 2}SeTe{sub 2} (a III-VI semiconductor) is directly influenced by the periodicity of its intrinsic defect structures. Specimens with periodic and semi-periodic two-dimensional vacancy structures become amorphous around 10–11?GPa in contrast to those with aperiodic structures, which amorphize around 7–8?GPa. The result is an instance of altering material phase-change properties via rearrangement of stoichiometric vacancies as opposed to adjusting their concentrations. Based on our experimental findings, we posit that periodic two-dimensional vacancy structures in Ga{sub 2}SeTe{sub 2} provide an energetically preferred crystal lattice that is less prone to collapse under applied pressure. This is corroborated through first-principles electronic structure calculations, which demonstrate that the energy stability of III-VI structures under hydrostatic pressure is highly dependent on the configuration of intrinsic vacancies.

  20. Observation of an electron band above the Fermi level in FeTe?.??Se?.?? from in-situ surface doping

    SciTech Connect (OSTI)

    Zhang, P.; Richard, P.; Xu, N.; Xu, Y. -M.; Ma, J.; Qian, T.; Fedorov, A. V.; Denlinger, J. D.; Gu, G. D.; Ding, H.

    2014-10-27

    We used in-situ potassium (K) evaporation to dope the surface of the iron-based superconductor FeTe?.??Se?.??. The systematic study of the bands near the Fermi level confirms that electrons are doped into the system, allowing us to tune the Fermi level of this material and to access otherwise unoccupied electronic states. In particular, we observe an electron band located above the Fermi level before doping that shares similarities with a small three-dimensional pocket observed in the cousin, heavily-electron-doped KFe??xSe? compound.

  1. Solar-energy conversion by combined photovoltaic converters with CdTe and CuInSe{sub 2} base layers

    SciTech Connect (OSTI)

    Khrypunov, G. S. Sokol, E. I.; Yakimenko, Yu. I.; Meriuts, A. V.; Ivashuk, A. V.; Shelest, T. N.

    2014-12-15

    The possibility of the combined use of bifacial thin-film solar cells based on CdTe and frontal solar cells with a CuInSe{sub 2} base layer in tandem structures is experimentally confirmed. It is found that, for the use of bifacial solar cells based on cadmium telluride in a tandem structure, the optimal thickness of their base layer should be 1 ?m. The gain in the efficiency of the tandem structure, compared with an individual CuInSe{sub 2}-based solar cell, is 1.8% in the case of series-connected solar cells and 1.3%, for parallel-connected.

  2. Comparison of crystal growth and thermoelectric properties of n-type Bi-Se-Te and p-type Bi-Sb-Te nanocrystalline thin films: Effects of homogeneous irradiation with an electron beam

    SciTech Connect (OSTI)

    Takashiri, Masayuki, E-mail: takashiri@tokai-u.jp; Imai, Kazuo; Uyama, Masato; Nishi, Yoshitake [Department of Materials Science, Tokai University, 4-1-1 Kitakaname, Hiratsuka, Kanagawa 259-1292 (Japan); Hagino, Harutoshi; Miyazaki, Koji [Department of Mechanical and Control Engineering, Kyushu Institute of Technology, 1-1 Sensui, Tobata-ku, Kitakyushu 804-8550 (Japan); Tanaka, Saburo [Department of Mechanical Engineering, College of Engineering, Nihon University, Nakagawara, Tokusada, Tamuramachi, Koriyama, Fukushima 963-8642 (Japan)

    2014-06-07

    The effects of homogenous electron beam (EB) irradiation on the crystal growth and thermoelectric properties of n-type Bi-Se-Te and p-type Bi-Sb-Te thin films were investigated. Both types of thin films were prepared by flash evaporation, after which homogeneous EB irradiation was performed at an acceleration voltage of 0.17?MeV. For the n-type thin films, nanodots with a diameter of less than 10?nm were observed on the surface of rice-like nanostructures, and crystallization and crystal orientation were improved by EB irradiation. The resulting enhancement of mobility led to increased electrical conductivity and thermoelectric power factor for the n-type thin films. In contrast, the crystallization and crystal orientation of the p-type thin films were not influenced by EB irradiation. The carrier concentration increased and mobility decreased with increased EB irradiation dose, possibly because of the generation of defects. As a result, the thermoelectric power factor of p-type thin films was not improved by EB irradiation. The different crystallization behavior of the n-type and p-type thin films is attributed to atomic rearrangement during EB irradiation. Selenium in the n-type thin films is more likely to undergo atomic rearrangement than the other atoms present, so only the crystallinity of the n-type Bi-Se-Te thin films was enhanced.

  3. Enhancement of transition temperature in Fe{sub x}Se{sub 0.5}Te{sub 0.5} film via iron vacancies

    SciTech Connect (OSTI)

    Zhuang, J. C. [Department of Physics and Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 211189 (China); Institute for Superconducting and Electronic Materials, University of Wollongong, North Wollongong, New South Wales 2500 (Australia); Yeoh, W. K., E-mail: waikong.yeoh@sydney.edu.au, E-mail: zxshi@seu.edu.cn [Institute for Superconducting and Electronic Materials, University of Wollongong, North Wollongong, New South Wales 2500 (Australia); Australian Centre for Microscopy and Microanalysis, University of Sydney, Sydney, New South Wales 2006 (Australia); School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney, Sydney, New South Wales 2006 (Australia); Cui, X. Y.; Ringer, S. P. [Australian Centre for Microscopy and Microanalysis, University of Sydney, Sydney, New South Wales 2006 (Australia); School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney, Sydney, New South Wales 2006 (Australia); Kim, J. H.; Shi, D. Q.; Wang, X. L.; Dou, S. X. [Institute for Superconducting and Electronic Materials, University of Wollongong, North Wollongong, New South Wales 2500 (Australia); Shi, Z. X., E-mail: waikong.yeoh@sydney.edu.au, E-mail: zxshi@seu.edu.cn [Department of Physics and Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 211189 (China)

    2014-06-30

    The effects of iron deficiency in Fe{sub x}Se{sub 0.5}Te{sub 0.5} thin films (0.8???x???1) on superconductivity and electronic properties have been studied. A significant enhancement of the superconducting transition temperature (T{sub C}) up to 21?K was observed in the most Fe deficient film (x?=?0.8). Based on the observed and simulated structural variation results, there is a high possibility that Fe vacancies can be formed in the Fe{sub x}Se{sub 0.5}Te{sub 0.5} films. The enhancement of T{sub C} shows a strong relationship with the lattice strain effect induced by Fe vacancies. Importantly, the presence of Fe vacancies alters the charge carrier population by introducing electron charge carriers, with the Fe deficient film showing more metallic behavior than the defect-free film. Our study provides a means to enhance the superconductivity and tune the charge carriers via Fe vacancy, with no reliance on chemical doping.

  4. Investigation of scanning tunneling spectra on iron-based superconductor FeSe0.5Te0.5(in Chinese)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Du, Z. -Y.; Fang, D. -L.; Wang, Z. -Y.; Du, G.; Yang, X.; Yang, H.; Gu, G.; -H, Wen H.

    2015-05-05

    FeSe0.5Te0.5 single crystals with superconducting critical temperature of 13.5 K are investigated by scanning tunneling microscopy/spectroscopy (STM/STS) measureflents in detail. STM image on the top surface shows an atomically resolved square lattice consisted by white and dark spots with a constant of about 3.73± 0.03 Å which is consistent with the lattice constant 3.78 Å. The Se and Te atoms with a height difference of about 0.35 Å are successfully identified since the sizes of the two kinds of atoms are different. The tunneling spectra show very large zero-bias conductance value and asymmetric coherent peaks in the superconducting state. Accordingmore »to the positions of coherence peaks, we determine the superconducting gap 2? = 5.5 meV, and the reduced gap 2?/kBTc = 4.9 is larger than the value predicted by the weak-coupling BCS theory. The zero-bias conductance at 1.7 K only have a decrease of about 40% compared with the normal state conductance, which may originate from some scattering and broadening mechanism in the material. This broadening effect will also make the superconducting gap determined by the distance between the coherence peaks larger than the exact gap value. The asymmetric structure of the tunneling spectra near the superconducting gap is induced by the hump on the background. This hump appears at temperature more than twice the superconducting critical temperature. This kind of hump has also been observed in other iron pnictides and needs further investigation. A possible bosonic mode outside the coherence peak with a mode energy ? of about 5.5 meV is observed in some tunneling spectra, and the ratio between the mode energy and superconducting transition temperature ?/kBTc ? 4.7 is roughly consistent with the universal ratio 4.3 in iron-based superconductors. The high-energy background of the spectra beyond the superconducting gaps shows a V-shape feature. The slopes of the differential conductance spectra at high energy are very different in the areas of Te-atom cluster and Se-atom cluster, and the difference extends to the energy of more than 300 meV. The differential conductance mapping has very little information about the quasi-particle interference of the superconducting state, which may result from the other strong scattering mechanism in the sample.« less

  5. Mechanical and thermal properties of h-MX{sub 2} (M?=?Cr, Mo, W; X?=?O, S, Se, Te) monolayers: A comparative study

    SciTech Connect (OSTI)

    Çak?r, Deniz, E-mail: deniz.cakir@uantwerpen.be; Peeters, François M., E-mail: francois.peeters@uantwerpen.be [Department of Physics, University of Antwerp, 2610 Antwerpen (Belgium); Sevik, Cem, E-mail: csevik@anadolu.edu.tr [Department of Mechanical Engineering, Faculty of Engineering, Anadolu University, Eskisehir TR 26555 (Turkey)

    2014-05-19

    Using density functional theory, we obtain the mechanical and thermal properties of MX{sub 2} monolayers (where M?=?Cr, Mo, W and X?=?O, S, Se, Te). The ?-centered phonon frequencies (i.e., A{sub 1}, A{sub 2}{sup ?}, E?, and E?), relative frequency values of A{sub 1}, and E? modes, and mechanical properties (i.e., elastic constants, Young modulus, and Poisson's ratio) display a strong dependence on the type of metal and chalcogenide atoms. In each chalcogenide (metal) group, transition-metal dichalcogenides (TMDCs) with W (O) atom are found to be much stiffer. Consistent with their stability, the thermal expansion of lattice constants for TMDCs with O (Te) is much slower (faster). Furthermore, in a heterostructure of these materials, the difference of the thermal expansion of lattice constants between the individual components becomes quite tiny over the whole temperature range. The calculated mechanical and thermal properties show that TMDCs are promising materials for heterostructures.

  6. Substitution of Ni for Fe in superconducting Fe?.??Te?.?Se?.? depresses the normal-state conductivity but not the magnetic spectral weight

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, Jinghui; Tranquada, J. M.; Zhong, Ruidan; Li, Shichao; Gan, Yuan; Xu, Zhijun; Zhang, Cheng; Ozaki, T.; Matsuda, M.; Zhao, Yang; et al

    2015-01-05

    We have performed systematic resistivity and inelastic neutron scattering measurements on Fe?.???zNizTe?.?Se?.? samples to study the impact of Ni substitution on the transport properties and the low-energy (? 12 meV) magnetic excitations. It is found that, with increasing Ni doping, both the conductivity and superconductivity are gradually suppressed; in contrast, the low-energy magnetic spectral weight changes little. Comparing with the impact of Co and Cu substitution, we find that the effects on conductivity and superconductivity for the same degree of substitution grow systematically as the atomic number of the substituent deviates from that of Fe. The impact of the substituentsmore »as scattering centers appears to be greater than any contribution to carrier concentration. The fact that low-energy magnetic spectral weight is not reduced by increased electron scattering indicates that the existence of antiferromagnetic correlations does not depend on electronic states close to the Fermi energy.« less

  7. Substitution of Ni for Fe in superconducting Fe?.??Te?.?Se?.? depresses the normal-state conductivity but not the magnetic spectral weight

    SciTech Connect (OSTI)

    Wang, Jinghui [Nanjing Univ., Nanjing (China); Tranquada, J. M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Zhong, Ruidan [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., Stony Brook, NY (United States); Li, Shichao [Nanjing Univ., Nanjing (China); Gan, Yuan [Nanjing Univ., Nanjing (China); Xu, Zhijun [Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Zhang, Cheng [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., Stony Brook, NY (United States); Ozaki, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Matsuda, M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Zhao, Yang [National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States); Univ. of Maryland, College Park, MD (United States); Li, Qiang [Brookhaven National Lab. (BNL), Upton, NY (United States); Xu, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gu, Genda [Brookhaven National Lab. (BNL), Upton, NY (United States); Birgeneau, R. J. [Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wen, Jinsheng [Nanjing Univ., Nanjing (China)

    2015-01-01

    We have performed systematic resistivity and inelastic neutron scattering measurements on Fe?.???zNizTe?.?Se?.? samples to study the impact of Ni substitution on the transport properties and the low-energy (? 12 meV) magnetic excitations. It is found that, with increasing Ni doping, both the conductivity and superconductivity are gradually suppressed; in contrast, the low-energy magnetic spectral weight changes little. Comparing with the impact of Co and Cu substitution, we find that the effects on conductivity and superconductivity for the same degree of substitution grow systematically as the atomic number of the substituent deviates from that of Fe. The impact of the substituents as scattering centers appears to be greater than any contribution to carrier concentration. The fact that low-energy magnetic spectral weight is not reduced by increased electron scattering indicates that the existence of antiferromagnetic correlations does not depend on electronic states close to the Fermi energy.

  8. Substitution of Ni for Fe in superconducting Fe?.??Te?.?Se?.? depresses the normal-state conductivity but not the magnetic spectral weight

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, Jinghui [Nanjing Univ., Nanjing (China); Tranquada, J. M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Zhong, Ruidan [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., Stony Brook, NY (United States); Li, Shichao [Nanjing Univ., Nanjing (China); Gan, Yuan [Nanjing Univ., Nanjing (China); Xu, Zhijun [Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Zhang, Cheng [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., Stony Brook, NY (United States); Ozaki, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Matsuda, M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Zhao, Yang [National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States); Univ. of Maryland, College Park, MD (United States); Li, Qiang [Brookhaven National Lab. (BNL), Upton, NY (United States); Xu, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gu, Genda [Brookhaven National Lab. (BNL), Upton, NY (United States); Birgeneau, R. J. [Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wen, Jinsheng [Nanjing Univ., Nanjing (China)

    2015-01-01

    We have performed systematic resistivity and inelastic neutron scattering measurements on Fe?.???zNizTe?.?Se?.? samples to study the impact of Ni substitution on the transport properties and the low-energy (? 12 meV) magnetic excitations. It is found that, with increasing Ni doping, both the conductivity and superconductivity are gradually suppressed; in contrast, the low-energy magnetic spectral weight changes little. Comparing with the impact of Co and Cu substitution, we find that the effects on conductivity and superconductivity for the same degree of substitution grow systematically as the atomic number of the substituent deviates from that of Fe. The impact of the substituents as scattering centers appears to be greater than any contribution to carrier concentration. The fact that low-energy magnetic spectral weight is not reduced by increased electron scattering indicates that the existence of antiferromagnetic correlations does not depend on electronic states close to the Fermi energy.

  9. Heat Capacity And Structural Relaxation In Se{sub 80-x}Te{sub 20}Ag{sub x}(x = 3 and 9) Glassy Alloys

    SciTech Connect (OSTI)

    Naqvi, S. Faheem; Saxena, N. S. [Semi-conductor and Polymer Science Laboratory, 5-6, Vigyan Bhawan, Department of Physics, University of Rajasthan, Jaipur-302004 (India)

    2011-10-20

    This paper reports the effects of annealing time and temperature on the thermodynamics of enthalpy relaxation of Se{sub 80-x}Te{sub 20}Ag{sub x} (x = 3,9) glasses. Differential Scanning Calorimetry (DSC) method is optimized for the measurement of enthalpy relaxation in the vicinity of glass transition. The recovery of excess enthalpy ({Delta}H{sub excess}) has been calculated from the knowledge of excess specific heat ({Delta}C{sub p}). It is found that excess enthalpy released ({Delta}H{sub excess}) increase with increase in annealing time (t{sub a}). From the knowledge of excess specific heat ({Delta}C{sub p}) and {Delta}H{sub excess}, it has been found that sub-T{sub g} annealing of glass leads to decrease in enthalpy of the system and thereby taking it to the more equilibrium state.

  10. Point defects in CdTexSe1-x crystals grown from a Te-rich solution for applications in detecting radiation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gul, R.; Roy, U. N.; Bolotnikov, A. E.; Camarda, G. S.; Cui, Y.; Hossain, A.; Lee, W.; Yang, G.; Burger, A.; James, R. B.; et al

    2015-04-15

    We investigated cadmium telluride selenide (CdTeSe) crystals, newly grown by the Traveling Heater Method (THM), for the presence and abundance of point defects. Deep Level Transient spectroscopy (I-DLTS) was used to determine the energies of the traps, their capture cross sections, and densities. The bias across the detectors was varied from (1–30) V. Four types of point defects were identified, ranging from 10 meV to 0.35 eV. Two dominant traps at energies of 0.18 eV and 0.14 eV were studied in depth. Cd vacancies are found at lower concentrations than other point defects present in the material.

  11. Electronic structure of antifluorite Cu{sub 2}X (X = S, Se, Te) within the modified Becke-Johnson potential plus an on-site Coulomb U

    SciTech Connect (OSTI)

    Zhang, Yubo; Wang, Youwei; Xi, Lili; Qiu, Ruihao; Shi, Xun; Zhang, Peihong E-mail: pzhang3@buffalo.edu; Beijing Computational Science Research Center, Beijing 100084 ; Zhang, Wenqing E-mail: pzhang3@buffalo.edu; School of Chemistry and Chemical Engineering, and Sate Key Laboratory of Coordination Chemistry, Nanjing University, Jiangsu 210093

    2014-02-21

    The traditional photon absorbers Cu{sub 2?x}X (X = S, Se, and Te) have regained significant research attention in the search of earth-abundant photovoltaic materials. These moderate- and narrow-gap materials have also been shown to exhibit excellent thermoelectric properties recently. However, semimetallic band structures with inverted band orderings are predicted for antifluorite structure Cu{sub 2}X using density functional theory with the local density approximation or the generalized gradient approximation. We find that semiconducting band structures and normal band orderings can be obtained using the modified Becke-Johnson potential plus an on-site Coulomb U (the mBJ+U approach), which is consistent with our earlier finding for diamond-like Cu-based multinary semiconductors [Y. Zhang, J. Zhang, W. Gao, T. A. Abtew, Y. Wang, P. Zhang, and W. Zhang, J. Chem. Phys. 139, 184706 (2013)]. The trend of the chemical bonding of Cu{sub 2}X is analyzed, which shows that the positions of the valence band maximum and conduction band minimum are strongly affected by the inter-site pd and intra-site sp hybridizations, respectively. The calculated gaps of Cu{sub 2}S and Cu{sub 2}Se still seem to be underestimated compared with experimental results. We also discuss the effects of different structural phases and Cu disordering and deficiency on the bandgaps of these materials.

  12. Electronic structure of lanthanum copper oxychalcogenides LaCuOCh (Ch=S, Se, Te) by X-ray photoelectron and absorption spectroscopy

    SciTech Connect (OSTI)

    Rudyk, Brent W.; Blanchard, Peter E.R.; Cavell, Ronald G. [Department of Chemistry, University of Alberta, Edmonton, Alberta, T6G 2G2 (Canada); Mar, Arthur, E-mail: arthur.mar@ualberta.ca [Department of Chemistry, University of Alberta, Edmonton, Alberta, T6G 2G2 (Canada)

    2011-07-15

    X-ray photoelectron spectroscopy (XPS) and X-ray absorption near-edge spectroscopy (XANES) have been applied to examine the electronic structures of lanthanum copper oxychalcogenides LaCuOCh (Ch=S, Se, Te), whose structure has been conventionally viewed as consisting of nominally isolated [LaO] and [CuCh] layers. However, there is evidence for weak La-Ch interactions between these layers, as seen in small changes in the satellite intensity of the La 3d XPS spectra as the chalcogen is changed and as supported by band structure calculations. The O 1s and Cu 2p XPS spectra are insensitive to chalcogen substitution. Lineshapes in the Cu 2p XPS spectra and fine-structure in the Cu L- and M-edge XANES spectra support the presence of Cu{sup +} species. The Ch XPS spectra show negative BE shifts relative to the elemental chalcogen, indicative of anionic species; these shifts correlate well with greater difference in electronegativity between the Cu and Ch atoms, provided that an intermediate electronegativity is chosen for Se. - Graphical abstract: The presence of anionic chalcogen atoms in LaCuOCh is supported by the Ch binding energies, which undergo negative shifts proportional to the polarity of the Cu-Ch bonds. Highlights: > La 3d XPS confirms La-Ch interlayer interactions between [LaO] and [CuCh] layers. > O 1s and Cu 2p XPS are insensitive to chalcogen substitution. > Cu XANES spectra support the presence of Cu{sup +} species. > Negative shifts in Ch binding energies imply anionic chalcogen atoms.

  13. Comparison of Sn-doped and nonstoichiometric vertical-Bridgman-grown crystals of the topological insulator Bi{sub 2}Te{sub 2}Se

    SciTech Connect (OSTI)

    Kushwaha, S. K. Gibson, Q. D.; Cava, R. J.; Xiong, J.; Ong, N. P.; Pletikosic, I.; Weber, A. P.; Fedorov, A. V.; Valla, T.

    2014-04-14

    A comparative study of the properties of topological insulator Bi{sub 2}Te{sub 2}Se (BTS) crystals grown by the vertical Bridgeman method is described. Two defect mechanisms that create acceptor impurities to compensate for the native n-type carriers are compared: Bi excess, and light Sn doping. Both methods yield low carrier concentrations and an n-p crossover over the length of the grown crystal boules, but lower carrier concentrations and higher resistivities are obtained for the Sn-doped crystals, which reach carrier concentrations as low as 8?×?10{sup 14}?cm{sup ?3}. Further, the temperature dependent resistivities for the Sn-doped crystals display strongly activated behavior at high temperatures, with a characteristic energy of half the bulk band gap. The (001) cleaved Sn-doped BTS crystals display high quality Shubnikov de Haas (SdH) quantum oscillations due to the topological surface state electrons. Angle resolved photoelectron spectroscopy (ARPES) characterization shows that the Fermi energy (E{sub F}) for the Sn-doped crystals falls cleanly in the surface states with no interference from the bulk bands, which the Dirac point for the surface states lies approximately 60?meV below the top of the bulk valence band maximum, and allows for a determination of the bulk and surface state carrier concentrations as a function of Energy near E{sub F}. Electronic structure calculations that compare Bi excess and Sn dopants in BTS demonstrate that Sn acts as a special impurity, with a localized impurity band that acts as a charge buffer occurring inside the bulk band gap. We propose that the special resonant level character of Sn in BTS gives rise to the exceptionally low carrier concentrations and activated resistivities observed.

  14. Structural and conductivity studies of CsK(SO{sub 4}){sub 0.32}(SeO{sub 4}){sub 0.68}Te(OH){sub 6}

    SciTech Connect (OSTI)

    Djemel, M.; Abdelhedi, M.; Dammak, M.; Kolsi, A.W.

    2012-12-15

    The compound CsK(SO{sub 4}){sub 0.32}(SeO{sub 4}){sub 0.68}Te(OH){sub 6} crystallizes in the monoclinic P2{sub 1}/n space group. It was analyzed, at room temperature, using X-ray diffractometer data. The main feature of these atomic arrangements is the coexistence of three and different anions (SO{sub 4}{sup 2-}, SeO{sub 4}{sup 2-} and TeO{sub 6}{sup 6-}groups) in the unit cell, connected by hydrogen bonds which make the building of the crystal. The thermal analysis of the title compound shows three distinct endothermal peaks at 435, 460 and 475 K. Complex impedance measurements are performed on this material as a function of both temperature and frequency. The electric conduction has been studied. The temperature dependence on the conductivity indicates that the sample became an ionic conductor at high temperature. - Graphical abstract: Projection of crystal structure CsK(SO{sub 4}){sub 0.32}(SeO{sub 4}){sub 0.68}Te(OH){sub 6} on the ab plane. Highlights: Black-Right-Pointing-Pointer We have studied the results of the crystal structure of the new mixed compound. Black-Right-Pointing-Pointer We have characterized the phase transition observed in DSC curve. Black-Right-Pointing-Pointer The protonic conduction in our material is probably due to a hopping mechanism.

  15. Observation of an electron band above the Fermi level in FeTe{sub 0.55}Se{sub 0.45} from in-situ surface doping

    SciTech Connect (OSTI)

    Zhang, P.; Ma, J.; Qian, T.; Richard, P. Ding, H.; Xu, N.; Xu, Y.-M.; Fedorov, A. V.; Denlinger, J. D.; Gu, G. D.

    2014-10-27

    We used in-situ potassium (K) evaporation to dope the surface of the iron-based superconductor FeTe{sub 0.55}Se{sub 0.45}. The systematic study of the bands near the Fermi level confirms that electrons are doped into the system, allowing us to tune the Fermi level of this material and to access otherwise unoccupied electronic states. In particular, we observe an electron band located above the Fermi level before doping that shares similarities with a small three-dimensional pocket observed in the cousin, heavily electron-doped KFe{sub 2?x}Se{sub 2} compound.

  16. Substitution of Ni for Fe in superconducting Fe0.98Te0.5Se0.5 depresses the normal-state conductivity but not the magnetic spectral weight

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, Jinghui; Zhong, Ruidan; Li, Shichao; Gan, Yuan; Xu, Zhijun; Zhang, Cheng; Ozaki, T.; Matsuda, M.; Zhao, Yang; Li, Qiang; et al

    2015-01-05

    We have performed systematic resistivity and inelastic neutron scattering measurements on Fe?.???zNizTe?.?Se?.? samples to study the impact of Ni substitution on the transport properties and the low-energy (? 12 meV) magnetic excitations. It is found that, with increasing Ni doping, both the conductivity and superconductivity are gradually suppressed; in contrast, the low-energy magnetic spectral weight changes little. Comparing with the impact of Co and Cu substitution, we find that the effects on conductivity and superconductivity for the same degree of substitution grow systematically as the atomic number of the substituent deviates from that of Fe. The impact of the substituentsmore »as scattering centers appears to be greater than any contribution to carrier concentration. The fact that low-energy magnetic spectral weight is not reduced by increased electron scattering indicates that the existence of antiferromagnetic correlations does not depend on electronic states close to the Fermi energy.« less

  17. Determination of lateral size distribution of type-II ZnTe/ZnSe stacked submonolayer quantum dots via spectral analysis of optical signature of the Aharanov-Bohm excitons

    SciTech Connect (OSTI)

    Ji, Haojie; Dhomkar, Siddharth; Roy, Bidisha; Kuskovsky, Igor L.; Shuvayev, Vladimir; Deligiannakis, Vasilios; Tamargo, Maria C.; Ludwig, Jonathan; Smirnov, Dmitry; Wang, Alice

    2014-10-28

    For submonolayer quantum dot (QD) based photonic devices, size and density of QDs are critical parameters, the probing of which requires indirect methods. We report the determination of lateral size distribution of type-II ZnTe/ZnSe stacked submonolayer QDs, based on spectral analysis of the optical signature of Aharanov-Bohm (AB) excitons, complemented by photoluminescence studies, secondary-ion mass spectroscopy, and numerical calculations. Numerical calculations are employed to determine the AB transition magnetic field as a function of the type-II QD radius. The study of four samples grown with different tellurium fluxes shows that the lateral size of QDs increases by just 50%, even though tellurium concentration increases 25-fold. Detailed spectral analysis of the emission of the AB exciton shows that the QD radii take on only certain values due to vertical correlation and the stacked nature of the QDs.

  18. Studies on the Bi[subscript 2]Te[subscript 3]–Bi[subscript 2]Se[subscript 3]–Bi[subscript 2]S[subscript 3] system for mid-temperature thermoelectric energy conversion

    E-Print Network [OSTI]

    Liu, Weishu

    Bismuth telluride (Bi[subscript 2]Te[subscript 3]) and its alloys have been widely investigated as thermoelectric materials for cooling applications at around room temperature. We report a systematic study on many compounds ...

  19. Understanding of the contact of nanostructured thermoelectric n-type Bi[subscript 2]Te[subscript 2.7]Se[subscript 0.3] legs for power generation applications

    E-Print Network [OSTI]

    Liu, Weishu

    Traditional processes of making contacts (metallization layer) onto bulk crystalline Bi2Te3-based materials do not work for nanostructured thermoelectric materials either because of weak bonding strength or an unstable ...

  20. Ann bay lodyans 6 / se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01

    ("Tonton Liben") ki pare ti liv sa a. AYITI SE PEP AYISYEN PM 7 8 5 4 .H39 A 5 6 2 0 0 0 V . 6 Enstiti Etid Ayisyen - Inivesite Kannzas Bon Nouvel Fondasyon Alfa Lwes 1997 PINGALOT AK ELIFET Vwala te gen yon wa ki rele Pingalot. Men wa sa a... te yon neg sitelman rayisab tout peyi a t ap soufri. Nan peyi sa a te gen yon msye ki rele Elifet. Se te yon bon moun ki te konn travay di, e ki te fe ekonomi jous li rive monte yon gwo kay menm pi bel pase kay wa a. Konsa, Pingalot moveanpil...

  1. De de se

    E-Print Network [OSTI]

    Anand, Pranav

    2006-01-01

    In this dissertation, I argue against a unitary treatment of individual de se ascription. Based on consideration of Yoruba logophors and English dream-report pronouns, I show that one mechanism is best analyzed as binding ...

  2. PHaSe-EFRC

    Broader source: All U.S. Department of Energy (DOE) Office Webpages

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory of rare Kaonforsupernovae model (JournalHearingsHuman CapitalOmega LaserPHaSe

  3. THROUGH-THE-GLASS SPECTROSCOPIC ELLIPSOMETRY OF CdTe SOLAR CELLS

    E-Print Network [OSTI]

    Rockett, Angus

    THROUGH-THE-GLASS SPECTROSCOPIC ELLIPSOMETRY OF CdTe SOLAR CELLS Jie Chen 1 , Jian Li 1 , Courtney of the optical structure of CdTe solar cells on transparent conducting oxide (TCO) coated glass superstrates. SE components from the coated glass before solar cell fabrication. A step-by-step fitting procedure identifies

  4. Enhanced Thermoelectric Properties of Solution Grown Bi2Te3-xSex Nanoplatelet Composites

    E-Print Network [OSTI]

    Xiong, Qihua

    Enhanced Thermoelectric Properties of Solution Grown Bi2Te3-xSex Nanoplatelet Composites Ajay Soni on the enhanced thermoelectric properties of selenium (Se) doped bismuth telluride (Bi2Te3-xSex) nanoplatelet (NP transport measure- ments, we show that both the thermoelectric power S (-259 V/K) and the figure of merit ZT

  5. High Compositional Homogeneity of CdTexSe1-x Crystals Grown by the Bridgman Method

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Roy, U. N.; Bolotnikov, A. E.; Camarda, G. S.; Cui, Y.; Hossain, A.; Lee, K.; Lee, W.; Tappero, R.; Yang, G.; Gul, R.; et al

    2015-02-03

    We obtained high-quality CdTexSe1-x (CdTeSe) crystals from ingots grown by the vertical Bridgman technique. The compositional uniformity of the ingots was evaluated by X-ray fluorescence at BNL’s National Synchrotron Light Source X27A beam line. The resulting compositional homogeneity was highly uniform throughout the ingot, and the effective segregation coefficient of Se was ~1.0. This uniformity offers potential opportunity to enhance the yield of the materials for both infrared substrate and radiation-detector applications, so greatly lowering the cost of production and also offering us the prospect to grow large-diameter ingots for use as large-area substrates and for producing higher efficiency gamma-raymore »detectors. The concentration of secondary phases was found to be much lower, by eight- to ten fold compared to that of conventional CdxZn1-xTe (CdZnTe or CZT).« less

  6. Potential thermoelectric performance from optimization of hole-doped Bi2Se3

    SciTech Connect (OSTI)

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

    2011-01-01

    We present an analysis of the potential thermoelectric performance of hole-doped Bi2Se3, which is commonly considered to show inferior room temperature performance when compared to Bi2Te3. We find that if the lattice thermal conductivity can be reduced by nanostructuring techniques (as have been applied to Bi2Te3) the material may show optimized ZT values of unity or more in the 300 - 500 K temperature range and thus be suitable for cooling and moderate temperature waste heat recovery and thermoelectric solar cell applications. Central to this conclusion are the larger band gap and the relatively heavier valence bands of Bi2Se3.

  7. Ann bay lodyans 15 / Se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01

    Liben”) ki pare ti liv sa a. [Lawrence, Kan.] : Institute of Haitian Studies ; [Port-au-Prince] : Bon Nouvèl : Fondasyon Alfa Lwès, 2000. Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml ANN BAY LODYANS15 Se Bryant Freeman ("Tonton Liben...") ki pare ti liv sa a. H ^ AYITI SE PEP AYISYEN 2 0 0 0 Enstiti Etid Ayisyen - Inivesite Kannzas Bon Nouvel Fondasyon Alfa Lwes 2000 PM 7854 .H39 A56 2000 v. 15 YON KONTRA AK LEDJAB Vwala te gen yon malerez ki te deja gen douz pitit, e...

  8. Ann bay lodyans 3 / se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01

    Liben”) ki pare ti liv sa a. [Lawrence, Kan.] : Institute of Haitian Studies ; [Port-au-Prince] : Bon Nouvèl : Fondasyon Alfa Lwès, 2000. Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml ANN BAY LODYANS 3 Se Bryant Freeman ("Tonton Liben...") ki pare ti liv sa a. AYITI SE PEP AYISYEN Enstiti Etid Ayisyen - Inivesite Kannzas Bon Nouvel Fondasyon Alfa Lwes 2000 PM 7854 • H39 A56 KUAN POU M JWENN KOB? Vwala te gen yon zarenyen ki te raze net. Li di nan tet li: "M bezwen jwenn kob...

  9. Neutron capture of /sup 122/Te, /sup 123/Te, /sup 124/Te, /sup 125/Te, and /sup 126/Te

    SciTech Connect (OSTI)

    Macklin, R.L.; Winters, R.R.

    1989-07-01

    Isotopically enriched samples of the tellurium isotopes from mass 122 to mass 126 were used to measure neutron capture in the energy range 2.6 keV to 600 keV at the Oak Ridge Electron Linear Accelerator pulsed neutron source. Starting at 2.6 keV, over 200 Breit-Wigner resonances for each isotope were used to describe the capture data. Least-squares adjustment gave parameters and their uncertainties for a total of 1659 resonances. Capture cross sections averaged over Maxwellian neutron distributions with temperatures ranging from kT = 5 keV to kT = 100 keV were derived for comparison with stellar nucleosynthesis calculations. For the three isotopes shielded from the astrophysical r-process, /sup 122/Te, /sup 123/Te and /sup 124/Te at kT = 30 keV the respective values were (280 /plus minus/ 10) mb, (819 /plus minus/ 30) mb and (154 /plus minus/ 6) mb. The corresponding products of cross section and solar system abundance are nearly equal in close agreement with s-process nucleosynthesis calculations. 26 refs., 8 figs., 10 tabs.

  10. Highly efficient nonradiative energy transfer using charged CdSe/ZnS nanocrystals for light-harvesting in solution

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    % in solution. CdTe and CdSe/ZnS dots of different sizes have further been studied for energy trans- fer in filmHighly efficient nonradiative energy transfer using charged CdSe/ZnS nanocrystals for light-harvesting in solution Evren Mutlugün,a Sedat Nizamolu, and Hilmi Volkan Demirb Department of Physics; Department

  11. Thin-film Sb2Se3 photovoltaics with oriented one-dimensional ribbons and benign

    E-Print Network [OSTI]

    Sargent, Edward H. "Ted"

    to the substrate, and produced Sb2Se3 thin-film solar cells with a certified device efficiency of 5.6%. Our results are one of the major limiting factors for high-efficiency thin-film solar cells. We began with first cells based on inorganic absorbers, such as Si, GaAs, CdTe and Cu(In,Ga)Se2, permit a high device

  12. Uso de Desinfectantes en Programas de Limpieza Verde Los desinfectantes y sanitizantes se usan en la mayora de programas de limpieza. Los desinfectantes

    E-Print Network [OSTI]

    Oliver, Douglas L.

    ser enjuagados con agua. Lo mismo sucede cuando te lavas las manos con jabón y agua o cuando lavas instrucciones en la etiqueta. Si usas un concentrado, asegúrate que se mezcle el químico con la cantidad de agua

  13. Semiconductor quantum dots enhanced graphene/CdTe heterostructure solar cells by photo-induced doping

    E-Print Network [OSTI]

    Li, Xiaoqiang; Wang, Peng; Xu, Zhijuan; Zhong, Huikai; Wu, Zhiqian; Lin, Shisheng

    2015-01-01

    Photo-induced doping is employed into graphene based solar cell through designing of a novel type of solar cell based on graphene/CdTe Schottky heterostructure. By coating a layer of ultrathin CdSe quantum dots onto graphene/CdTe heterostructure, the performance of the graphene/CdTe solar cell is improved by about 50%. Photo-induced doping is mainly accounted for this enhancement, as evidenced by resistance, photoluminescence and quantum efficiency measurements. This work demonstrates a general and feasible way of designing novel type of solar cells based on two dimensional materials/semiconductor heterostructures.

  14. Ann bay lodyans 10 / Se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01

    KU ScholarWorks | http://kuscholarworks.ku.edu Ann Bay Lodyans 10 se Bryant Freeman (“Tonton Liben”) ki pare ti liv sa a 2000 by Bryant C. Freeman, ed. This work has been made available by the University of Kansas Libraries’ Office of Scholarly... Freeman (“Tonton Liben”) ki pare ti liv sa a. [Lawrence, Kan.] : Institute of Haitian Studies ; [Port-au-Prince] : Bon Nouvèl : Fondasyon Alfa Lwès, 2000. Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml Tl CHENN LO A Te gen yon nonm ki te...

  15. Ann bay lodyans 8 / se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01

    Liben”) ki pare ti liv sa a. [Lawrence, Kan.] : Institute of Haitian Studies ; [Port-au-Prince] : Bon Nouvèl : Fondasyon Alfa Lwès, 2000. Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml YON TOTI K AP CHANTE Vwala te gen yon neg yo rele... Gwoje. Msye te konn plante diri. Chak ane li pa janm ka fe bon rekot. Bet yo pran tout plezi yo nan manje jaden diri a. Se konsa, Gwoje blije mete veye pou trape vole k ap depafini jaden I la. Yon jou, pandan Pijon ak Kanna ap soti pou al nan jaden...

  16. Materials Data on Ga2TeSe2 (SG:109) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  17. Phototropic growth control of nanoscale pattern formation in photoelectrodeposited SeTe films

    E-Print Network [OSTI]

    Faraon, Andrei

    field would provide a remarkable route to the synthesis of complex 3D mesostructures via feedback between illumination and the structure that develops under optical excitation. We report the spontaneous that change under illumination are enabling for the photolithographic generation of patterns in 2D and 3D

  18. Solon SE | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-Enhancing Capacity forSiliciumEnergy Inc Jump to:Solergy PowerSolisSolmicSolomonSE

  19. Elastic properties of sulphur and selenium doped ternary PbTe alloys by first principles

    SciTech Connect (OSTI)

    Bali, Ashoka, E-mail: rcmallik@physics.iisc.ernet.in; Chetty, Raju, E-mail: rcmallik@physics.iisc.ernet.in; Mallik, Ramesh Chandra, E-mail: rcmallik@physics.iisc.ernet.in [Thermoelectric Materials and Devices Laboratory, Department of Physics, Indian Institute of Science, Bangalore-560012 (India)

    2014-04-24

    Lead telluride (PbTe) is an established thermoelectric material which can be alloyed with sulphur and selenium to further enhance the thermoelectric properties. Here, a first principles study of ternary alloys PbS{sub x}Te{sub (1?x)} and PbSe{sub x}Te{sub (1?x)} (0?x?1) based on the Virtual Crystal Approximation (VCA) is presented for different ratios of the isoelectronic atoms in each series. Equilibrium lattice parameters and elastic constants have been calculated and compared with the reported data. Anisotropy parameter calculated from the stiffness constants showed a slight improvement in anisotropy of elastic properties of the alloys over undoped PbTe. Furthermore, the alloys satisfied the predicted stability criteria from the elastic constants, showing stable structures, which agreed with the previously reported experimental results.

  20. Members of a workshop at the tenth IAYC Conference, July 7, 2006 1. ge -hak -te le -ber, ge -fil -te -fish: sha-bes iz a far -ge -ni -gn

    E-Print Network [OSTI]

    Finkel, Raphael

    A SUDE Members of a workshop at the tenth IAYC Conference, July 7, 2006 = 90 4 4 1. ge - hak - te le - ber, ge - fil - te - fish: sha- bes iz a far - ge - ni - gn 2. kha - le gri - vn, ku - gl yoykh: ku - men on di ma - khe - to - nem. 3. shtru - dl, tsi - mes, zi - se kalte: a su - de vos men vet ge

  1. Efficient band alignment for ZnxCd1xSe QD-sensitized TiO2 solar cells

    E-Print Network [OSTI]

    Cao, Guozhong

    dots (QDs), such as CdS,2,3 CdTe,4­6 PbS,7,8 PbSe,9,10 and InP,11,12 have recently been extensively in the enhancement of the power conversion efficiency and device stability. As an alternative, semiconductor quantum

  2. Ann bay lodyans 4 / se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01

    KU ScholarWorks | http://kuscholarworks.ku.edu Ann Bay Lodyans 4 se Bryant Freeman (“Tonton Liben”) ki pare ti liv sa a 2000 by Bryant C. Freeman, ed. This work has been made available by the University of Kansas Libraries’ Office of Scholarly... Freeman (“Tonton Liben”) ki pare ti liv sa a. [Lawrence, Kan.] : Institute of Haitian Studies ; [Port-au-Prince] : Bon Nouvèl : Fondasyon Alfa Lwès, 2000. Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml Tl CHAT: PI PITI PI RED Vwala se te...

  3. Ann bay lodyans 5 / se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01

    Liben”) ki pare ti liv sa a. [Lawrence, Kan.] : Institute of Haitian Studies ; [Port-au-Prince] : Bon Nouvèl : Fondasyon Alfa Lwès, 2000. Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml ANN BAY LODYANS 5 Se Bryant Freeman ("Tonton Liben.... Tijo we yon tig ki te tonbe nan yon gwo twou. Li pa t kapab soti paske twou a fon. Kounye a tig la prizonye. Li di Tijo: "Ou se yon bon ti gason, ede m soti, souple." Tijo reponn: "Si mwen retire ou nan twou a, ou ap manje m." Tig la di: "O non...

  4. Ann bay lodyans 16 / Se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01

    ofisye yo. Genyen yon gwo pyano pou nou pote nan sal la." Pye Wolen, Senlwidino TET DESALIN Yon blan rantre an Ayiti. Li mande yon neg: "Fe m jwenn tet Jan Jak Desalin, pou souvni." Neg la, sa li gen pou fe, li rantre nan yon simitye, li pran yon... tet byen vit. Li pote I bay blan an. Blan an di konsa: "Sa a pa tet Desalin. Tet Desalin pa kapab piti konsa." Neg la di: "Sa a se tet Desalin le I te timoun!" 8 MANGO A Ml Se Bouki ak Malis ki t ap pwonmennen. Bouki di Malis: "Men yon pye mango...

  5. Superconductivity in Strong Spin Orbital Coupling Compound Sb2Se3

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kong, P. P.; Sun, F.; Xing, L. Y.; Zhu, J.; Zhang, S. J.; Li, W. M.; Liu, Q. Q.; Wang, X. C.; Feng, S. M.; Yu, X. H.; et al

    2015-02-17

    Recently, A2B3 type strong spin orbital coupling compounds such as Bi2Te3, Bi2Se3 and Sb2Te3 were theoretically predicated to be topological insulators and demonstrated through experimental efforts. The counterpart compound Sb2Se3 on the other hand was found to be topological trivial, but theoretical studies indicated that the pressure might induce Sb2Se3 into a topological nontrivial state. We report on the discovery of superconductivity in Sb2Se3 single crystal induced via pressure. Our experiments indicated that Sb2Se3 became superconductive at high pressures above 10 GPa proceeded by a pressure induced insulator to metal like transition at ~3 GPa which should be related tomore »the topological quantum transition. The superconducting transition temperature (TC) increased to around 8.0 K with pressure up to 40 GPa while it keeps ambient structure. High pressure Raman revealed that new modes appeared around 10 GPa and 20 GPa, respectively, which correspond to occurrence of superconductivity and to the change of TC slop as the function of high pressure in conjunction with the evolutions of structural parameters at high pressures.« less

  6. Recycling of CdTe photovoltaic waste

    DOE Patents [OSTI]

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

    1999-01-01

    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.

  7. The Precipitation of Sb2Te3 in Sb-rich AgSbTe2 via the Intermediate...

    Office of Scientific and Technical Information (OSTI)

    The Precipitation of Sb2Te3 in Sb-rich AgSbTe2 via the Intermediate Phase (AgSb)3Te4. Citation Details In-Document Search Title: The Precipitation of Sb2Te3 in Sb-rich AgSbTe2 via...

  8. Computermathematik Einfuhrung in LaTeX

    E-Print Network [OSTI]

    Auzinger, Winfried

    TeX (I: Einf., II: Erg¨anz., III: Erweiterungen) Addison Wesley 22000 (I), 21997 (II), 1996 (III) Tobias

  9. Recycling ZnTe, CdTe, and Other Compound Semiconductors by Ambipolar Electrolysis

    E-Print Network [OSTI]

    Osswald, Sebastian

    The electrochemical behavior of ZnTe and CdTe compound semiconductors dissolved in molten ZnCl[subscript 2] and equimolar CdCl[subscript 2]–KCl, respectively, was examined. In these melts dissolved Te is present as the ...

  10. LaTeX Original

    E-Print Network [OSTI]

    ... mostraron algoritmos que permiten obtener parámetros de anisotro? a que representan en promedio la región donde se efectuan experimentos de fracking.

  11. CdTe devices and method of manufacturing same

    DOE Patents [OSTI]

    Gessert, Timothy A.; Noufi, Rommel; Dhere, Ramesh G.; Albin, David S.; Barnes, Teresa; Burst, James; Duenow, Joel N.; Reese, Matthew

    2015-09-29

    A method of producing polycrystalline CdTe materials and devices that incorporate the polycrystalline CdTe materials are provided. In particular, a method of producing polycrystalline p-doped CdTe thin films for use in CdTe solar cells in which the CdTe thin films possess enhanced acceptor densities and minority carrier lifetimes, resulting in enhanced efficiency of the solar cells containing the CdTe material are provided.

  12. Galp associa se melhor escola de petrleo

    E-Print Network [OSTI]

    Instituto de Sistemas e Robotica

    juntaram-se à Galp para criar o ISPG, que se associou à Heriot Watt University para criar um mestrado em de uma parceria entre o ISPG e a Heriot Watt University, considera- da a melhor instituição de qualificado e de I&D deste sector para as operações que desenvolve em muitos países lusófo- nos, como Brasil

  13. University Ave SE University Ave W

    E-Print Network [OSTI]

    Thomas, David D.

    University Ave SE University Ave W Service Layer Credits: Sources: Esri, DeLorme, NAVTEQ, USGS, Intermap, i UV55 ")280 University Ave. Ramp Major Access Routes University Ave. Ramp §¨¦35W §¨¦94 ")280 Date: 5/30/2014 #12;, , , , , , , ""A TCF Bank Stadium Access Routes University Ave. Ramp University Ave SE Service

  14. Recycling of CdTe photovoltaic waste

    DOE Patents [OSTI]

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

    1999-04-27

    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.

  15. Recycling of CdTe photovoltaic waste

    DOE Patents [OSTI]

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

    1999-04-27

    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.

  16. The Roles of Cu Impurity States in CdTe Thin Film Solar Cells Ken K. Chin1

    E-Print Network [OSTI]

    as commercially successful, second generation thin film photovoltaic (PV) products, at a production cost of $0 PV technologies, such as Cu(In,Ga)Se2 (CIGS), which has a lower theoretical limit ~26% but a higher involves Cu impurities. The CdTe thin film uses low cost 5N tellurium, which, either as a byproduct

  17. GaTe semiconductor for radiation detection

    DOE Patents [OSTI]

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

    2009-06-23

    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.

  18. Half Life of {sup 127}Te

    SciTech Connect (OSTI)

    Batista, Wagner F.; Genezini, Frederico A.; Zamboni, Cibele B.; Zahn, Guilherme S. [Centro do Reator de Pesquisas (CRPq)-Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP). Av. Linneu Prestes, 2242-Cidade Universitaria, Sao Paulo, SP, 05507-000 (Brazil)

    2009-06-03

    In this work, the half life of the beta-unstable nucleus {sup 127}Te was studied using neutron-irradiated samples of {sup 126}Te. The gamma activity of each of the irradiated samples was followed for 3-5 consecutive half lives. The results were analysed in two different ways, and the resulting half-life was 9.295(5)h, which is compatible with the tabulated value of 9.35(7)h, with much lower uncertainty.

  19. REPRESENTATIVE COURSE SEQUENCE SOFTWARE ENGINEERING (SE)

    E-Print Network [OSTI]

    Huang, Haiying

    REPRESENTATIVE COURSE SEQUENCE SOFTWARE ENGINEERING (SE) Freshman Year First Semester Second Semester Second Semester CSE 3310 ­ Fundamentals of Software CSE 3302 ­ Programming Languages Engineering CSE 3320 ­ Operating Systems CSE 3315 ­ Theoretical Concepts in CSE CSE 4310 ­ Software Engineering

  20. Enriched $^{82}$Se for the LUCIFER experiment

    E-Print Network [OSTI]

    J. W. Beeman; F. Bellini; P. Benetti; L. Cardani; N. Casali; D. Chiesa; M. Clemenza; I. Dafinei; S. Di Domizio; F. Ferroni; L. Gironi; A. Giuliani; C. Gotti; M. Laubenstein; M. Maino; S. Nagorny; S. Nisi; C. Nones; F. Orio; L. Pagnanini; L. Pattavina; G. Pessina; G. Piperno; S. Pirro; E. Previtali; C. Rusconi; K. Schäffner; C. Tomei; M. Vignati

    2015-08-07

    The LUCIFER project aims at deploying the first array of enriched scintillating bolometers for the investigation of neutrinoless double-beta decay of $^{82}$Se. The matrix which embeds the source is an array of ZnSe crystals, where enriched $^{82}$Se is used as decay isotope. The radiopurity of the initial components employed for manufacturing crystals, that can be operated as bolometers, is crucial for achieving a null background level in the region of interest for double-beta decay investigations. In this work, we evaluated the radioactive content in 2.5 kg of 96.3% enriched $^{82}$Se metal, measured with a high-purity germanium detector at the Gran Sasso deep underground laboratory. The limits on internal contaminations of primordial decay chain elements of $^{232}$Th, $^{238}$U and $^{235}$U are respectively: $<$61 $\\mu$Bq/kg, $<$110 $\\mu$Bq/kg and $<$74 $\\mu$Bq/kg at 90% C.L.. The extremely low-background conditions in which the measurement was carried out and the high radiopurity of the $^{82}$Se allowed us to establish the most stringent lower limits on the half-lives of the double-beta decay of $^{82}$Se to 0$^+_1$, 2$^+_2$ and 2$^+_1$ excited states of $^{82}$Kr of 3.4$\\cdot$10$^{22}$ y, 1.3$\\cdot$10$^{22}$ y and 1.0$\\cdot$10$^{22}$ y, respectively, with a 90% C.L..

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

    E-Print Network [OSTI]

    Desantis, S.

    2010-01-01

    CBP-836 THE TE WAVE TRANSMISSION METHOD FOR ELECTRON CLOUDon the optimization of TE Wave measurements at the Cesr-TALinear Collider. The TE Wave measurement method utilizes

  2. The Politics of Parody: Rosa Montero's Te trataré como a una reina and Patrick Süskind's Perfume

    E-Print Network [OSTI]

    Jurney, Florence Ramond

    1999-01-01

    by Misreading: Rosa Montero's Te Anales de la Literaturarapport sur de Minuit, 1979. Montero, Rosa. Te trataré comovol. xxviii The Rosa Montero's Te trataré conto a Politics

  3. Ann bay lodyans 7 / se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01

    la. Ti nonm Ian pa souke ko I tou. Wa a mete de men nan tet pou I rele. Konsa Wa a fe yo pran Malis, yo mete I nan yon sak, yo pandye I nan yon pyebwa annatandan yo voye I nan lanme. Malis t ap kalkile kisa pou I ta fe pou I chape, le de vole...." De vole yo tire oso, e se vole ki pi malen an ki antre nan sak la. Se konsa Malis rive chape anko. Sa gen kek jou depi yo te voye sak la nan lanme. Wa a t ap fe yon pwomnad, li pase devan kay Malis. Le I voye je I nan lakou a, sezisman manke touye...

  4. INTEGRAL observations of TeV plerions

    E-Print Network [OSTI]

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

    2006-09-14

    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.

  5. ARCHITECTURE OVERVIEW TIPSTER SE/CM

    E-Print Network [OSTI]

    ARCHITECTURE OVERVIEW TIPSTER SE/CM tipster@fipster.org THE TIPSTER ARCHITECTURE The TIPSTER Architecture is a software architecture for providing Document Detection (i.e. Document Retrieval and Message Routing) and Information Extraction functions to text handling applications. The high level architecture

  6. Enriched $^{82}$Se for the LUCIFER experiment

    E-Print Network [OSTI]

    Beeman, J W; Benetti, P; Cardani, L; Casali, N; Chiesa, D; Clemenza, M; Dafinei, I; Di Domizio, S; Ferroni, F; Gironi, L; Giuliani, A; Gotti, C; Laubenstein, M; Maino, M; Nagorny, S; Nisi, S; Nones, C; Orio, F; Pagnanini, L; Pattavina, L; Pessina, G; Piperno, G; Pirro, S; Previtali, E; Rusconi, C; Schäffner, K; Tomei, C; Vignati, M

    2015-01-01

    The LUCIFER project aims at deploying the first array of enriched scintillating bolometers for the investigation of neutrinoless double-beta decay of $^{82}$Se. The matrix which embeds the source is an array of ZnSe crystals, where enriched $^{82}$Se is used as decay isotope. The radiopurity of the initial components employed for manufacturing crystals, that can be operated as bolometers, is crucial for achieving a null background level in the region of interest for double-beta decay investigations. In this work, we evaluated the radioactive content in 2.5 kg of 96.3% enriched $^{82}$Se metal, measured with a high-purity germanium detector at the Gran Sasso deep underground laboratory. The limits on internal contaminations of primordial decay chain elements of $^{232}$Th, $^{238}$U and $^{235}$U are respectively: $<$61 $\\mu$Bq/kg, $<$110 $\\mu$Bq/kg and $<$74 $\\mu$Bq/kg at 90% C.L.. The extremely low-background conditions in which the measurement was carried out and the high radiopurity of the $^{82}$...

  7. NPS-SE-10-003 POSTGRADUATE

    E-Print Network [OSTI]

    NPS-SE-10-003 NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA INTEGRATED PROJECT An Integrated Command and Control Architecture Concept for Unmanned Systems in the Year of 2030 By Omari D Buckley reporting burden for this collection of information is estimated to average 1 hour per response, including

  8. TE resonances in graphene-dielectric structures

    E-Print Network [OSTI]

    Werra, Julia F M; Busch, Kurt

    2015-01-01

    An investigation of the dispersion relations of TE resonances in different graphene-dielectric structures is presented. When a graphene layer is brought into contact with a dielectric material, a gap can appear in its electric band structure. This allows for the formation of TE-plasmons with unusual dispersion relations. In addition, if the dielectric has a finite thickness, graphene acts as a mode filter and strongly modifies the behavior of the waveguiding modes by introducing a frequency cutoff. This cutoff and the properties of TE-plasmons are closely related to the pair-creation threshold of graphene thus representing quantum mechanical effects that manifest themselves in the electromagnetic response. Our findings are of particular relevance to all forms of light-matter interaction in graphene-based systems, notably for the decay rates of emitters that are in close proximity to graphene.

  9. Japanese Experiential -te iru as an Individual-Level Construction

    E-Print Network [OSTI]

    Sugita, Mamori

    2008-01-01

    Japanese Experiential -te iru as an Individual-Level Construction Mamori Sugita CUNY Graduate Center 1. Introduction The Japanese -te iru is best known as an aspectual form that yields progressive and perfective readings. The -te iru... form of an activity verb yields a progressive reading, and the -te iru form of an achievement verb yields a perfective reading. Many formal analyses of these two readings can be found in the literature (Ogihara, 1998; Shirai, 2000; Kusumoto, 2003; Mc...

  10. Benefits of Carrier Pocket Anisotropy to Thermoelectric Performance: The case of p-type AgBiSe2

    SciTech Connect (OSTI)

    Parker, David S; May, Andrew F; Singh, David J

    2015-01-01

    We study theoretically the effects of anisotropy on the thermoelectric performance of p-type AgBiSe2. We present an apparent realization of the thermoelectric benefits of one-dimensional plate-like carrier pocket anisotropy in the valence band of this material. Based on first principles calculations we find a substantial anisotropy in the electronic structure, likely favorable for thermoelectric performance, in the valence bands of the hexagonal phase of the silver chalcogenide thermoelectric AgBiSe2, while the conduction bands are more isotropic, and in our experiments do not attain high performance. AgBiSe2 has already exhibited a ZT value of 1.5 in a high-temperature disordered fcc phase, but room-temperature performance has not been demonstrated. We develop a theory for the ability of anisotropy to decouple the density-of-states and conductivity effective masses, pointing out the influence of this effect in the high performance thermoelectrics Bi2Te3 and PbTe. From our first principles and Boltzmann transport calculations we find that p-type AgBiSe2 has substantial promise as a room temperature thermoelectric, and estimate its performance.

  11. Structural and electronic properties of -In2X3 (X=O, S, Se, Te) using ab initio calculations

    E-Print Network [OSTI]

    Khare, Sanjay V.

    by NREL [1]. CdS is one of the important layers in fabricating CIGS solar cells but poses ecological and environmentally friendly copper­indium­gallium­selenide solar cells and molecules. Here we have studied been investigated. © 2011 Elsevier B.V. All rights reserved. Introduction Cu­In­Ga­S (CIGS) based solar

  12. Influence of CdTe thickness on structural and electrical properties of CdTe/CdS solar cells

    E-Print Network [OSTI]

    Romeo, Alessandro

    Influence of CdTe thickness on structural and electrical properties of CdTe/CdS solar cells A a b s t r a c ta r t i c l e i n f o Available online xxxx Keywords: Solar cells CdCl2 CdTe Thin absorbers Due to its high scalability and low production cost, CdTe solar cells have shown a very strong

  13. Semitransparent ultrathin CdTe solar cells Semitransparent ultrathin CdTe solar cells and durabilityand durability

    E-Print Network [OSTI]

    Rollins, Andrew M.

    Semitransparent ultrathin CdTe solar cells Semitransparent ultrathin CdTe solar cells lines · Thinfilm CIGS--not available in transparent form · Dye sensitized solar thin films· Dye.E. McCandless, W.A. Buchanan. "High throughput processing of CdTe/CdS solar cells with thin absorber

  14. Q Cells SE | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop Inc Jump to:Newberg,Energy LLCALLETE Inc dEAPrysmianPvT Capital GmbhQ Cells SE

  15. Investigation of band inversion in (Pb,Sn)Te alloys using ab initio calculations Xing Gao and Murray S. Daw

    E-Print Network [OSTI]

    Daw, Murray S.

    - ductors occurs at the point. Also, the order of the band gap Eg PbS Eg PbTe Eg PbSe and the order and the L6 - state forming the valence band edge. The change in Eg with alloying is ascribed to the dif is consistent with the observed variation of Eg with x and the change in the sign of the temperature

  16. New chalcogenide glasses in the CdTe-AgI-As{sub 2}Te{sub 3} system

    SciTech Connect (OSTI)

    Kassem, M.; Le Coq, D.; Boidin, R.; Bychkov, E.; ULCO, LPCA, EA 4493, F-59140 Dunkerque

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer Determination of the glass-forming region in the pseudo-ternary CdTe-AgI-As{sub 2}Te{sub 3} system. Black-Right-Pointing-Pointer Characterization of macroscopic properties of the new CdTe-AgI-As{sub 2}Te{sub 3} glasses. Black-Right-Pointing-Pointer Characterization of the total conductivity of CdTe-AgI-As{sub 2}Te{sub 3} glasses. Black-Right-Pointing-Pointer Comparison between the selenide and telluride equivalent systems. -- Abstract: Chalcogenide glasses in the pseudo-ternary CdTe-AgI-As{sub 2}Te{sub 3} system were synthesized and the glass-forming range was determined. The maximum content of CdTe in this glass system was found to be equal to 15 mol.%. The macroscopic characterizations of samples have consisted in Differential Scanning Calorimetry, density, and X-ray diffraction measurements. The cadmium telluride addition does not generate any significant change in the glass transition temperature but the resistance of binary AgI-As{sub 2}Te{sub 3} glasses towards crystallisation is estimated to be decreasing on the base of {Delta}T = T{sub x} - T{sub g} parameter. The total electrical conductivity {sigma} was measured by complex impedance spectroscopy. First, the CdTe additions in the (AgI){sub 0.5}(As{sub 2}Te{sub 3}){sub 0.5} host glass, (CdTe){sub x}(AgI){sub 0.5-x/2}(As{sub 2}Te{sub 3}){sub 0.5-x/2} lead to a conductivity decrease at x {<=} 0.05. Then, the behaviour is reversed at 0.05 {<=} x {<=} 0.15. The obtained results are discussed by comparison with the equivalent selenide system.

  17. Scientific Achievement Networks of highly photoresponsive crystalline GaSe

    E-Print Network [OSTI]

    Geohegan, David B.

    Scientific Achievement Networks of highly photoresponsive crystalline GaSe nanosheets a crystalline GaSe target was adjusted to directly grow networks of interconnected triangular GaSe crystalline nanosheets of ~ 200 nm size (inset shows atomic

  18. Nanoscale structure in AgSbTe2 determined by diffuse elastic neutron scattering

    SciTech Connect (OSTI)

    Specht, Eliot D [ORNL; Ma, Jie [ORNL; Delaire, Olivier A [ORNL; Budai, John D [ORNL; May, Andrew F [ORNL; Karapetrova, Evguenia A. [Argonne National Laboratory (ANL)

    2015-01-01

    Diffuse elastic neutron scattering measurements confirm that AgSbTe2 has a hierarchical structure, with defects on length scales from nanometers to microns. While scattering from mesoscale structure is consistent with previously-proposed structures in which Ag and Sb order on a NaCl lattice, more diffuse scattering from nanoscale structure suggests a structural rearrangement in which hexagonal layers form a combination of (ABC), (ABA), and (AAB) stacking sequences. The AgCrSe2 structure is the best-fitting model for the local atomic arrangements.

  19. Reaction kinetics of a-CuInSe2 formation from an In2Se3/CuSe bilayer precursor film

    E-Print Network [OSTI]

    Anderson, Timothy J.

    with Ga or S are proven absorber materials for high efficiency thin film solar cells. Interestingly CIGS system using the stacked elemental film precursors (e.g. glass/Cu/In/Se, glass/Cu/Se, glass

  20. Graphene TE Surface Plasmon Detection using Nonreciprocity Modal Discrimination

    E-Print Network [OSTI]

    Chamanara, Nima

    2015-01-01

    We present a magnetically biased graphene-ferrite structure discriminating the TE and TM plasmonic modes of graphene. In this structure, the graphene TM plasmons interact reciprocally with the structure. In contrast, the graphene TE plasmons exhibit nonreciprocity. This nonreciprocity is manifested in different phases and losses of surface plasmons for opposite directions of propagation. The proposed structure provides a unique platform for the experimental demonstration of the unusual existence of the TE plasmonic mode in graphene.

  1. A Search for Neutrinoless Double Beta Decay of Te-130

    E-Print Network [OSTI]

    Bryant, Adam Douglas

    2010-01-01

    far unobserved, neutrinoless double beta decay is a possibleright for the neutrinoless double beta decay of 130 Te. Thisprocess, with neutrinoless double beta decay being the most

  2. Recognition of the Coherence Relation between Te-linked Clauses

    E-Print Network [OSTI]

    -sareta. typhoon-NOM come-te houses-NOM destroy- PASSIVE-PAST "A typhoon came, and houses were destroyed." 1The

  3. High performance Zintl phase TE materials with embedded nanoparticles...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Zintl phase TE materials with embedded nanoparticles Performance of zintl phase thermoelectric materials with embedded particles are evaluated shakouri.pdf More Documents &...

  4. Te Awatea Review The Journal of Te Awatea Violence Research Centre

    E-Print Network [OSTI]

    Hickman, Mark

    : Issues in Gender-based Violence in Aotearoa New Zealand Dr Annabel Taylor 12 Evaluation of Family Group The Potential of Co-location of Services in the NGO Sector in Christchurch: A Method of Improving Collaboration reflect the policies and views of Te Awatea Violence Research Centre. ISSN 1176-5259 (Print) ISSN 1178

  5. SE-72/AS-72 generator system based on Se extraction/ As reextraction

    DOE Patents [OSTI]

    Fassbender, Michael Ernst; Ballard, Beau D

    2013-09-10

    The preparation of a .sup.72Se/.sup.72As radioisotope generator involves forming an acidic aqueous solution of an irradiated alkali bromide target such as a NaBr target, oxidizing soluble bromide in the solution to elemental bromine, removing the elemental bromine, evaporating the resulting solution to a residue, removing hydrogen chloride from the residue, forming an acidic aqueous solution of the residue, adding a chelator that selectively forms a chelation complex with selenium, and extracting the chelation complex from the acidic aqueous solution into an organic phase. As the .sup.72Se generates .sup.72As in the organic phase, the .sup.72As may be extracted repeatedly from the organic phase with an aqueous acid solution.

  6. Copper migration in CdTe heterojunction solar cells

    SciTech Connect (OSTI)

    Chou, H.C.; Rohatgi, A.; Jokerst, N.M.; Thomas, E.W.; Kamra, S.

    1996-07-01

    CdTe solar cells were fabricated by depositing a Au/Cu contact with Cu thickness in the range of 50 to 150A on polycrystalline CdTe/CdS/SnO{sub 2} glass structures. The increase in Cu thickness improves ohmic contact and reduces series resistance (R{sub s}), but the excess Cu tends to diffuse into CdTe and lower shunt resistance (R{sub sh}) and cell performance. Light I-V and secondary ion mass spectroscopy (SIMS) measurements were performed to understand the correlations between the Cu contact thickness, the extent of Cu incorporation in the CdTe cells, and its impact on the cell performance. The CdTe/CdS/SnO{sub 2} glass, CdTe/CdS/GaAs, and CdTe/GaAs structures were prepared in an attempt to achieve CdTe films with different degrees of crystallinity and grain size. A large grain polycrystalline CdTe thin film solar cell was obtained for the first time by selective etching the GaAs substrate coupled with the film transfer onto a glass substrate. SIMS measurement showed that poor crystallinity and smaller grain size of the CdTe film promotes Cu diffusion and decreases the cell performance. Therefore, grain boundaries are the main conduits for Cu migration and larger CdTe grain size or alternate method of contact formation can mitigate the adverse effect of Cu and improve the cell performance. 15 refs., 1 fig.,6 tabs.

  7. Te Mihi Power Station | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-Enhancing CapacityVectren)ModelTalbotts LtdTarlton,Tazewell County, Illinois:Te Mihi

  8. TE Connectivity Finds Answers in Tomography

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired Solar Fuel Production 1:PhysicsSyndicated Contentwo2 TABLETCP2TE

  9. TE Connectivity Finds Answers in Tomography

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With LivermoreSustainable Landmimic keySystemssystemsoTE Connectivity

  10. MgSe/ZnSe/CdSe coupled quantum wells grown on InP substrate with intersubband absorption covering 1.55??m

    SciTech Connect (OSTI)

    Chen, Guopeng; Shen, Aidong; De Jesus, Joel; Tamargo, Maria C.

    2014-12-08

    The authors report the observation of intersubband (ISB) transitions in the optical communication wavelength region in MgSe/ZnSe/CdSe coupled quantum wells (QWs). The coupled QWs were grown on InP substrates by molecular beam epitaxy. By inserting ZnSe layers to compensate the strain, samples with high structural quality were obtained, as indicated by well resolved satellite peaks in high-resolution x-ray diffraction. The observed ISB transition energies agree well with the calculated values.

  11. 31P Solid State NMR Studies of Metal Selenophosphates Containing [P2Se6]4-, [P4Se10]4-, [PSe4]3-, [P2Se7]4-, and [P2Se9]4-Ligands

    E-Print Network [OSTI]

    Weliky, David

    31P Solid State NMR Studies of Metal Selenophosphates Containing [P2Se6]4-, [P4Se10]4-, [PSe4]3-, [P2Se7]4-, and [P2Se9]4- Ligands Christian G. Canlas, Mercouri G. Kanatzidis, and David P. Weliky P solid-state nuclear magnetic resonance (NMR) spectra of 12 metal-containing selenophosphates have

  12. COMPARISON OF CSS-CdTe AND PVD-CdTe WITH DIFFERENT ACTIVATION PROCESSES , G. Khrypunov2,4

    E-Print Network [OSTI]

    Romeo, Alessandro

    Energy Systems and Technology), Department of Electronic and Electrical Engineering, Loughborough) system at lower substrate temperatures (typically 300°C) has also provided solar cells with efficienciesCOMPARISON OF CSS-CdTe AND PVD-CdTe WITH DIFFERENT ACTIVATION PROCESSES A. Romeo1 , G. Khrypunov2

  13. Use of separate ZnTe interface layers to form ohmic contacts to p-CdTe films

    DOE Patents [OSTI]

    Gessert, T.A.

    1999-06-01

    A method of is disclosed 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 tellurium-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. 11 figs.

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

    DOE Patents [OSTI]

    Gessert, Timothy A. (Conifer, CO)

    1999-01-01

    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.

  15. Twinning effect on photoluminescence spectra of ZnSe nanowires

    SciTech Connect (OSTI)

    Xu, Jing; Wang, Chunrui Wu, Binhe; Xu, Xiaofeng; Chen, Xiaoshuang; Oh, Hongseok; Baek, Hyeonjun; Yi, Gyu-Chul

    2014-11-07

    Bandgap engineering in a single material along the axial length of nanowires may be realized by arranging periodic twinning, whose twin plane is vertical to the axial length of nanowires. In this paper, we report the effect of twin on photoluminescence of ZnSe nanowires, which refers to the bandgap of it. The exciton-related emission peaks of transverse twinning ZnSe nanowires manifest a 10-meV-blue-shift in comparison with those of longitudinal twinning ZnSe nanowires. The blue-shift is attributed to quantum confinement effect, which is influenced severely by the proportion of wurtzite ZnSe layers in ZnSe nanowires.

  16. Spectral photoresponse of ZnSe/GaAs(001) heterostructures with CdSe ultra-thin quantum well insertions

    SciTech Connect (OSTI)

    Valverde-Chávez, D. A.; Sutara, F.; Hernández-Calderón, I.

    2014-05-15

    We present a study of the spectral photoresponse (SPR) of ZnSe/GaAs(001) heterostructures for different ZnSe film thickness with and without CdSe ultra-thin quantum well (UTQW) insertions. We observe a significant increase of the SPR of heterostructures containing 3 monolayer thick CdSe UTQW insertions; these results encourage their use in photodetectors and solar cells.

  17. Electrochemically deposited BiTe-based nanowires for thermoelectric applications

    SciTech Connect (OSTI)

    Ng, Inn-Khuan; Kok, Kuan-Ying; Rahman, Che Zuraini Che Ab; Saidin, Nur Ubaidah; Ilias, Suhaila Hani; Choo, Thye-Foo [Malaysian Nuclear Agency, Bangi, 43000 Kajang, Selangor Darul Ehsan (Malaysia)

    2014-02-12

    Nanostructured materials systems such as thin-films and nanowires (NWs) are promising for thermoelectric power generation and refrigeration compared to traditional counterparts in bulk, due to their enhanced thermoelectric figures-of-merit. BiTe and its derivative compounds, in particular, are well-known for their near-room temperature thermoelectric performance. In this work, both the binary and ternary BiTe-based nanowires namely, BiTe and BiSbTe, were synthesized using template-assisted electrodeposition. Diameters of the nanowires were controlled by the pore sizes of the anodised alumina (AAO) templates used. Systematic study on the compositional change as a function of applied potential was carried out via Linear Sweep Voltanmetry (LSV). Chemical compositions of the nanowires were studied using Energy Dispersive X-ray Spectrometry (EDXS) and their microstructures evaluated using diffraction and imaging techniques. Results from chemical analysis on the nanowires indicated that while the Sb content in BiSbTe nanowires increased with more negative deposition potentials, the formation of Te{sup 0} and Bi{sub 2}Te{sub 3} were favorable at more positive potentials.

  18. CuInSe/sub 2/-based photoelectrochemical cells: their use in characterization of thin CuInSe/sub 2/ films, and as photovoltaic cells per se

    SciTech Connect (OSTI)

    Cahen, D.; Chen, Y.W.; Ireland, P.J.; Noufi, R.; Turner, J.A.; Rincon, C.; Bachmann, K.J.

    1984-05-01

    Photoelectrochemistry has been employed to characterize the p-CuInSe/sub 2/ component of the CdS/CuInSe/sub 2/ on-metal and a nonaqueous electrolyte containing a redox couple not specifically adsorbed onto the semiconductor, we can test the films for photovoltaic activity and obtain effective electronic properties of them, before CdS deposition, in a nondestructive manner. Electrochemical decomposition of CuInSe/sub 2/ was investigated in acetonitrile solutions to determine the mechanism of decomposition (n and p) in the dark and under illumination. Electrochemical, solution chemical and surface analyses confirmed at the light-assisted decomposition of CuInSe/sub 2/ resulted in metal ions and elemental chalcogen. On the basis of the results from the electrochemical decomposition, and studies on the solid state chemistry of the (Cu/sub 2/Se)/sub x/(In/sub 2/Se/sub 3/)/sub 1-x/ system and surface analyses, the CuInSe/sub 2//polyiodide interface was stabilized and up to 11.7% conversion efficiencies were obtained.

  19. A p ? n transition for Sn-doped Cu(In,Ga)Se{sub 2} bulk materials

    SciTech Connect (OSTI)

    Monsefi, Mehrdad; Kuo, Dong-Hau, E-mail: dhkuo@mail.ntust.edu.tw

    2013-08-15

    Cu(In,Ga)Se{sub 2} (CIGSe) pellets at different Sn contents were fabricated by reactive liquid-phase sintering at 600–700 °C with the help of sintering aids of Sb{sub 2}S{sub 3} and Te. Powder preparation was based upon the molecular formula of Cu{sub 0.9}[(In{sub 0.7?x}Sn{sub x}Ga{sub 0.3}){sub 0.9}Sb{sub 0.1}](S{sub 0.15}Te{sub 0.2}Se{sub 1.65}) or Sn-x-CIGSe. Morphology, structure, and electrical property of Sn-doped CIGSe bulks were investigated. The composition of Sn-doped CIGSe is purposely designed for studying the doping effect on the CIGSe performance. The unexpected increase in hole concentration of CIGSe due to the donor doping is rationalized. A controllable n-type semiconductor is deliberately achieved for Sn-0.15-CIGSe and important for making a p/n homojunction in CIGSe solar cells. - Graphical abstract: The controls in defect type and electrical properties of Cu(In,Ga)Se{sub 2} by doping Sn{sup 4+} on the In{sup 3+} site. Highlights: • n-type Sn-CIGSe with n{sub e} of 6.4×10{sup 16} cm{sup ?3} and ?{sub e} of 2.3 cm{sup 2}/V s was obtained. • This n-type Sn-CIGSe was obtained by material design and composition control. • The reported n-type CIGSe was obtained from the Zn/CIGSe and CdS/CIGSe bilayers. • Extrinsic donor doping was explored through the results of electrical properties. • A n/p homojunction with Sn-CIGSe and undoped one can be used for solar cell devices.

  20. Process Development for High Voc CdTe Solar Cells

    SciTech Connect (OSTI)

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

    2011-05-01

    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.

  1. Thermoelectric transport of Se-rich Ag{sub 2}Se in normal phases and phase transitions

    SciTech Connect (OSTI)

    Mi, Wenlong; Lv, Yanhong; Qiu, Pengfei; Shi, Xun E-mail: cld@mail.sic.ac.cn; Chen, Lidong E-mail: cld@mail.sic.ac.cn; Zhang, Tiansong

    2014-03-31

    Small amount of Se atoms are used to tune the carrier concentrations (n{sub H}) and electrical transport in Ag{sub 2}Se. Significant enhancements in power factor and thermoelectric figure of merit (zT) are observed in the compositions of Ag{sub 2}Se{sub 1.06} and Ag{sub 2}Se{sub 1.08}. The excessive Se atoms do not change the intrinsically electron-conducting character in Ag{sub 2}Se. The detailed analysis reveals the experiment optimum carrier concentration in Ag{sub 2}Se is around 5?×?10{sup 18}?cm{sup ?3}. We also investigate the temperature of maximum zT and the thermoelectric transport during the first order phase transitions using the recently developed measurement system.

  2. Glass formation and the third harmonic generation of Cu{sub 2}Se–GeSe{sub 2}–As{sub 2}Se{sub 3} glasses

    SciTech Connect (OSTI)

    Reshak, A. H.; Klymovych, O. S.; Zmiy, O. F.; Myronchuk, G. L.; Zamuruyeva, O. V.; Alahmed, Z. A.; Chyský, J.; Bila, Jiri; Kamarudin, H.

    2014-10-14

    We have performed the investigation of the nonlinear optical properties namely the third harmonic generation (THG) of the glass-formation region in the Cu{sub 2}Se–GeSe{sub 2}–As{sub 2}Se{sub 3} system. The samples were synthesized by direct single-temperature method from high-purity elementary substances. We have found that the value of disorder parameter ? depends on the composition of the glassy alloys. The measurements show that increasing the Cu{sub 2}Se concentration leads to increased slope of the absorption edge, which may be explained by the decrease of the height of random potential relief for the electrons in the tails of the state density which border the band edges. A very sharp increase in the THG at low temperature was observed. Significant enhancement in THG was obtained with decreasing the energy gap, which agreed well with the nonlinear optical susceptibilities obtained from other glasses.

  3. Electrical and photovoltaic properties of CdTe/ZnTe n-i-p junctions grown by molecular beam epitaxy

    SciTech Connect (OSTI)

    Zielony, E., E-mail: eunika.zielony@pwr.edu.pl; P?aczek-Popko, E.; Racino, A.; Gumienny, Z. [Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland); Olender, K.; Wosi?ski, T.; Karczewski, G.; Chusnutdinow, S. [Institute of Physics, Polish Academy of Sciences, al. Lotnikow 32/46, 02-668 Warsaw (Poland)

    2014-06-28

    Preliminary studies have been performed on photoelectrical properties of CdTe/ZnTe n-i-p junctions grown using the molecular beam epitaxy technique. Photovoltaic properties of the cells have been investigated by the measurements of current-voltage (I-V) characteristics under 1-sun illumination. I-V characteristics yield efficiencies of the cells varying from 3.4% to 4.9%. The low efficiency can be due to the presence of electrically active defects. In order to study the origin of defects in CdTe/ZnTe photovoltaic junctions, space charge techniques (C-V and deep level transient spectroscopy (DLTS)) have been applied. From the C-V measurements, a doping profile was calculated confirming charge accumulation in the i-CdTe layer. The results of the DLTS studies revealed the presence of four traps within a temperature range from 77–420?K. Three of them with activation energies equal to 0.22 eV, 0.45?eV, and 0.78?eV have been ascribed to the hole traps present in the i-CdTe material and their possible origin has been discussed. The fourth, high-temperature DLTS peak observed at ?350?K has been attributed to extended defects as its amplitude and temperature position depends on the value of the filling pulse width. It is assumed that the defects related to the trap are either located in the i-CdTe layer or at the i-CdTe/ZnTe interface. However, it was found that the trap exhibits twofold nature: it behaves as a majority or as a minority trap, depending on the filling pulse height, which is a characteristic feature of recombination centers. This trap is presumably responsible for the low efficiency of the cells.

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

    E-Print Network [OSTI]

    p-Doping limit and donor compensation in CdTe polycrystalline thin film solar cells Ken K. Chin n substitution of Cd CuCd 0=À #12; #12; play critical roles in p-doping of CdTe in CdS/CdTe thin film solar cells in Fig. 1. As for the CdTe polycrystalline thin film in a CdS/CdTe solar cell, it is still being debated

  5. Mat. Res. Soc. Symp. Proc. Vol. 668 @ 2001 Materials Research Society Influence of proton irradiation and development of flexible CdTe solar cells on polyimide

    E-Print Network [OSTI]

    Romeo, Alessandro

    investigations on Cu(In,Ga)Se2 (called CIGS) solar cells have proven that their stability against high energy cells on polymer films can yield more than 2- kW/kg specific power. CIGS solar cells of about 10 to 12 irradiation and development of flexible CdTe solar cells on polyimide A. Romeo, D.L. Bätzner, H. Zogg and A

  6. www.medicine.gu.se Minnesanteckningar forskarutbildningsutskottet, inst. fr medicin

    E-Print Network [OSTI]

    www.medicine.gu.se Minnesanteckningar forskarutbildningsutskottet, inst. för medicin 2015 inflammationsforskning hälsas välkommen som ny ledamot i FUU. Per Ladenvall vid avd. för molekylär och klinisk medicin

  7. Native defects in MBE-grown CdTe

    SciTech Connect (OSTI)

    Olender, Karolina; Wosinski, Tadeusz; Makosa, Andrzej; Tkaczyk, Zbigniew; Kolkovsky, Valery; Karczewski, Grzegorz

    2013-12-04

    Deep-level traps in both n- and p-type CdTe layers, grown by molecular-beam epitaxy on GaAs substrates, have been investigated by means of deep-level transient spectroscopy (DLTS). Four of the traps revealed in the DLTS spectra, which displayed exponential kinetics for capture of charge carriers into the trap states, have been assigned to native point defects: Cd interstitial, Cd vacancy, Te antisite defect and a complex formed of the Te antisite and Cd vacancy. Three further traps, displaying logarithmic capture kinetics, have been ascribed to electron states of treading dislocations generated at the mismatched interface with the substrate and propagated through the CdTe layer.

  8. Summary of the TeV33 working group

    SciTech Connect (OSTI)

    Bagley, P.P.; Bieniosek, F.M.; Colestock, P.

    1996-10-01

    This summary of the TeV33 working group at Snowmass reports on work in the areas of Tevatron store parameters, the beam-beam interaction, Main Injector intensity (slip stacking), antiproton production, and electron cooling.

  9. CdSe self-assembled quantum dots with ZnCdMgSe barriers emitting throughout the visible spectrum

    SciTech Connect (OSTI)

    Perez-Paz, M. Noemi; Zhou Xuecong; Munoz, Martin; Lu Hong; Sohel, Mohammad; Tamargo, Maria C.; Jean-Mary, Fleumingue; Akins, Daniel L.

    2004-12-27

    Self-assembled quantum dots of CdSe with ZnCdMgSe barriers have been grown by molecular beam epitaxy on InP substrates. The optical and microstructural properties were investigated using photoluminescence (PL) and atomic force microscopy (AFM) measurements. Control and reproducibility of the quantum dot (QD) size leading to light emission throughout the entire visible spectrum range has been obtained by varying the CdSe deposition time. Longer CdSe deposition times result in a redshift of the PL peaks as a consequence of an increase of QD size. AFM studies demonstrate the presence of QDs in uncapped structures. A comparison of this QD system with CdSe/ZnSe shows that not only the strain but also the chemical properties of the system play an important role in QD formation.

  10. Phonon self-energy and origin of anomalous neutron scattering spectra in SnTe and PbTe thermoelectrics

    SciTech Connect (OSTI)

    Li, Chen [ORNL] [ORNL; Ma, Jie [ORNL] [ORNL; May, Andrew F [ORNL] [ORNL; Cao, Huibo [ORNL] [ORNL; Christianson, Andrew D [ORNL] [ORNL; Ehlers, Georg [ORNL] [ORNL; Singh, David J [ORNL] [ORNL; Sales, Brian C [ORNL] [ORNL; Delaire, Olivier A [ORNL] [ORNL

    2014-01-01

    The anharmonic lattice dynamics of rock-salt thermoelectric compounds SnTe and PbTe are investigated with inelastic neutron scattering (INS) and first-principles calculations. The experiments show that, surprisingly, although SnTe is closer to the ferroelectric instability, phonon spectra in PbTe exhibit a more anharmonic character. This behavior is reproduced in first-principles calculations of the temperature-dependent phonon self-energy. Our simulations reveal how the nesting of phonon dispersions induces prominent features in the self-energy, which account for the measured INS spectra and their temperature dependence. We establish that the phase-space for three-phonon scattering processes, rather than just the proximity to the lattice instability, is the mechanism determining the complex spectrum of the transverse-optical ferroelectric mode.

  11. ME/SE 740 Vision, Robotics & Planning Spring 2009

    E-Print Network [OSTI]

    Lin, Xi

    ME/SE 740 ­ Vision, Robotics & Planning Spring 2009 Professor Pierre Dupont, Room 408, 110 Cummington Street 353-9596 pierre@bu.edu Required Text: A Mathematical Introduction to ROBOTIC MANIPULATION://www.engin.umich.edu/group/ctm/basic/basic.html #12;ME/SE 740 ­ Vision, Robotics & Planning 1/22/20092 Course Topics: 1. Introduction: · Historical

  12. APS/DPP 111207-se 1 University Fusion Association Meeting

    E-Print Network [OSTI]

    Eckstrand for Office of Fusion Energy Sciences Fusion Energy Sciences Program Update www.ofes.fusion.doe.gov U.S. Department of Energy's Office of Science #12;APS/DPP 111207-se 2 Topics · Budget status/DPP 111207-se 3 FY 2008 Fusion Energy Sciences Congressional Budget Request 144.6 146.3 20.8 311.7 FY 2007

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

    SciTech Connect (OSTI)

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

    2008-05-01

    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.

  14. Approved Module Information for SE4031, 2014/5 Module Title/Name: Extended Integrative Option Module Code: SE4031

    E-Print Network [OSTI]

    Neirotti, Juan Pablo

    Approved Module Information for SE4031, 2014/5 Module Title/Name: Extended Integrative Option Module Code: SE4031 School: Engineering and Applied Science Module Type: Standard Module New Module? No Module Credits: 30 Module Management Information Module Leader Name Trevor Oliver Email Address t

  15. Optical Probing of metamagnetic phases in epitaxial EuSe

    SciTech Connect (OSTI)

    Galgano, G. D.; Henriques, A. B.; Bauer, G.; Springholz, G.

    2011-12-23

    EuSe is a wide gap magnetic semiconductors with a potential for applications in proof-of-concept spintronic devices. When the temperature is lowered, EuSe goes through sharp transitions between a variety of magnetic phases and is thus described as metamagnetic. The purpose of the present investigation is to correlate the magnetic order to the sharp dichroic doublet, discovered recently in high quality thin epitaxial layers of EuSe, grown by molecular beam epitaxy. We report detailed measurements of the doublet positions and intensities as a function of magnetic field in low temperatures, covering several magnetic phases.

  16. The half-life of {sup 131g,m}Te

    SciTech Connect (OSTI)

    Ruivo, J. C.; Zamboni, C. B.; Oliveira, J. R. B.; Heder Medina, Nilberto

    2013-05-06

    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.

  17. Growth, steady-state, and time-resolved photoluminescence study of CdTe/MgCdTe double heterostructures on InSb substrates using molecular beam epitaxy

    SciTech Connect (OSTI)

    DiNezza, Michael J.; Liu, Shi; Kirk, Alexander P.; Zhang, Yong-Hang [Center for Photonics Innovation, Arizona State University, Tempe, Arizona 85287 (United States) [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); Zhao, Xin-Hao [Center for Photonics Innovation, Arizona State University, Tempe, Arizona 85287 (United States) [Center for Photonics Innovation, Arizona State University, Tempe, Arizona 85287 (United States); School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287 (United States)

    2013-11-04

    CdTe/MgCdTe double heterostructures (DHs) are grown on InSb substrates using molecular beam epitaxy and reveal strong photoluminescence with over double the intensity of a GaAs/AlGaAs DH with an identical layer structure design grown on GaAs. Time-resolved photoluminescence of the CdTe/MgCdTe DH gives a Shockley-Read-Hall recombination lifetime of 86 ns, which is more than one order of magnitude longer than that of typical polycrystalline CdTe films. These findings indicate that monocrystalline CdTe/MgCdTe DHs effectively reduce surface recombination, have limited nonradiative interface recombination, and are promising for solar cells that could reach power conversion efficiencies similar to that of GaAs.

  18. Enhanced thermoelectric power and electronic correlations in RuSe?

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, Kefeng; Wang, Aifeng; Tomic, A.; Wang, Limin; Abeykoon, A. M. Milinda; Dooryhee, E.; Billinge, S. J.L.; Petrovic, C.

    2015-03-03

    We report the electronic structure, electric and thermal transport properties of Ru??xIrxSe? (x ? 0.2). RuSe? is a semiconductor that crystallizes in a cubic pyrite unit cell. The Seebeck coefficient of RuSe? exceeds -200 µV/K around 730 K. Ir substitution results in the suppression of the resistivity and the Seebeck coefficient, suggesting the removal of the peaks in density of states near the Fermi level. Ru?.?Ir?.?Se? shows a semiconductor-metal crossover at about 30 K. The magnetic field restores the semiconducting behavior. Our results indicate the importance of the electronic correlations in enhanced thermoelectricity of RuSb?.

  19. Hot exciton transport in ZnSe quantum wells

    E-Print Network [OSTI]

    Zhao, Hui; Moehl, Sebastian; Wachter, Sven; Kalt, Heinz

    2002-02-01

    The in-plane transport of excitons in ZnSe quantum wells is investigated directly by microphotoluminescence in combination with a solid immersion lens. Due to the strong Froehlich coupling, the initial kinetic energy of the excitons is well...

  20. Optical Properties of CdSe Nanoparticle Assemblies

    SciTech Connect (OSTI)

    Huser, T; Gerion, D; Zaitseva, N; Krol, D M; Leon, F R

    2003-11-24

    We report on three-dimensional fluorescence imaging of micron-size faceted crystals precipitated from solutions of CdSe nanocrystals. Such crystals have previously been suggested to be superlattices of CdSe quantum dots [1,2]. Possible applications for these materials include their use in optical and optoelectronic devices. The micron-size crystals were grown by slow evaporation from toluene solutions of CdSe nanocrystals in the range of 3-6 nm, produced by traditional wet-chemistry techniques. By using a confocal microscope with laser illumination, three-dimensional raster-scanning and synchronized hyper-spectral detection, we have generated spatial profiles of the fluorescence emission intensity and spectrum. The fluorescence data of the micro-crystals were compared with spectra of individual nanocrystals obtained from the same solution. The results do not support the assertion that these microcrystals consist of CdSe superlattices.

  1. Milagro Observations of Potential TeV Emitters

    E-Print Network [OSTI]

    Abdo, A A; Allen, B T; Aune, T; Barber, A S; Berley, D; Braun, J; Chen, C; Christopher, G E; DeYoung, T; Dingus, B L; Ellsworth, R W; Gonzalez, M M; Goodman, J A; Hays, E; Hoffman, C M; Huntemeyer, P H; Imran, A; Kolterman, B E; Linnemann, J T; McEnery, J E; Morgan, T; Mincer, A I; Nemethy, P; Pretz, J; Ryan, J M; Parkinson, P M Saz; Schneider, M; Shoup, A; Sinnis, G; Smith, A J; Vasileiou, V; Walker, G P; Williams, D A; Yodh, G B

    2014-01-01

    This paper reports the results from three targeted searches of Milagro TeV sky maps: two extragalactic point source lists and one pulsar source list. The first extragalactic candidate list consists of 709 candidates selected from the Fermi-LAT 2FGL catalog. The second extragalactic candidate list contains 31 candidates selected from the TeVCat source catalog that have been detected by imaging atmospheric Cherenkov telescopes (IACTs). In both extragalactic candidate lists Mkn 421 was the only source detected by Milagro. This paper presents the Milagro TeV flux for Mkn 421 and flux limits for the brighter Fermi-LAT extragalactic sources and for all TeVCat candidates. The pulsar list extends a previously published Milagro targeted search for Galactic sources. With the 32 new gamma-ray pulsars identified in 2FGL, the number of pulsars that are studied by both Fermi-LAT and Milagro is increased to 52. In this sample, we find that the probability of Milagro detecting a TeV emission coincident with a pulsar increase...

  2. Computando lo aspero Por que se cuelgan las computadoras?

    E-Print Network [OSTI]

    Figueira, Santiago

    ejemplo 0 + 1 = 1. Tambi´en puedo al 1 sumarle 1 y obtener el 2: (0 + 1) + 1 = 2 recursi´on: una funci´on que se llama a s´i misma. Por ejemplo, a la funci´on suma se puede definir como: suma(m, n) = n si m´olo un peque~no n´umero de s´imbolos reciben atenci´on (en el ejemplo, 2). Hay una cantidad finita de s

  3. Synthesis and properties of new CdSe-AgI-As{sub 2}Se{sub 3} chalcogenide glasses

    SciTech Connect (OSTI)

    Kassem, M.; ULCO, LPCA, EAC CNRS 4493 F-59140 Dunkerque ; Le Coq, D.; Fourmentin, M.; Hindle, F.; Bokova, M.; Cuisset, A.; Masselin, P.; Bychkov, E.; ULCO, LPCA, EAC CNRS 4493 F-59140 Dunkerque

    2011-02-15

    Research highlights: {yields} Determination of the glass-forming region in the pseudo-ternary CdSe-AgI-As{sub 2}Se{sub 3} system. {yields} Characterization of macroscopic properties of the new CdSe-AgI-As{sub 2}Se{sub 3} glasses. {yields} Far infrared transmission of chalcogenide glasses. {yields} Characterization of the total conductivity of CdSe-AgI-As{sub 2}Se{sub 3} glasses. -- Abstract: The glass-forming region in the pseudo-ternary CdSe-AgI-As{sub 2}Se{sub 3} system was determined. Measurements including differential scanning calorimetry (DSC), density, and X-ray diffraction were performed. The effect resulting from the addition of CdSe or AgI has been highlighted by examining three series of different base glasses. The characteristic temperatures of the glass samples, including glass transition (T{sub g}), crystallisation (T{sub x}), and melting (T{sub m}) temperatures are reported and used to calculate their {Delta}T = T{sub x} - T{sub g} and their Hruby, H{sub r} = (T{sub x} - T{sub g})/(T{sub m} - T{sub x}), criteria. Evolution of the total electrical conductivity {sigma} and the room temperature conductivity {sigma}{sub 298} was also studied. The terahertz transparency domain in the 50-600 cm{sup -1} region was pointed for different chalcogenide glasses (ChGs) and the potential of the THz spectroscopy was suggested to obtain structural information on ChGs.

  4. Giant Anharmonic Phonon Scattering in PbTe

    SciTech Connect (OSTI)

    Delaire, Olivier A [ORNL; Ma, Jie [ORNL; Marty, Karol J [ORNL; May, Andrew F [ORNL; McGuire, Michael A [ORNL; Singh, David J [ORNL; Lumsden, Mark D [ORNL; Sales, Brian C [ORNL; Du, Mao-Hua [ORNL; Ehlers, Georg [ORNL; Podlesnyak, Andrey A [ORNL

    2011-01-01

    Understanding the microscopic processes affecting the bulk thermal conductivity is crucial to develop more efficient thermoelectric materials. PbTe is currently one of the leading thermoelectric materials, largely thanks to its low thermal conductivity. However, the origin of this low thermal conductivity in a simple rocksalt structure has so far been elusive. Using a combination of inelastic neutron scattering measurements and first-principles computations of the phonons, we identify a strong anharmonic coupling between the ferroelectric transverse optic (TO) mode and the longitudinal acoustic (LA) modes in PbTe. This interaction extends over a large portion of reciprocal space, and directly affects the heat-carrying LA phonons. The LA-TO anharmonic coupling is likely to play a central role in explaining the low thermal conductivity of PbTe. The present results provide a microscopic picture of why many good thermoelectric materials are found near a lattice instability of the ferroelectric type.

  5. Giant Piezoelectricity in Monolayer Group IV Monochalcogenides: SnSe, SnS, GeSe and GeS

    E-Print Network [OSTI]

    Fei, Ruixiang; Li, Ju; Yang, Li

    2015-01-01

    We predict enormous piezoelectric effects in intrinsic monolayer group IV monochalcogenides (MX, M=Sn or Ge, X=Se or S), including SnSe, SnS, GeSe and GeS. Using first-principle simulations based on the modern theory of polarization, we find that their characteristic piezoelectric coefficients are about two orders of magnitude larger than those of other 2D materials, such as MoS2 and GaSe, and bulk quartz and AlN which are widely used in industry. This enhancement is a result of the unique "puckered" D2h symmetry and weaker chemical bonds of monolayer group IV monochalcogenides. Given the achieved experimental advances in fabrication of monolayers, their flexible character and ability to withstand enormous strain, these 2D structures with giant piezoelectric effects may be promising for a broad range of applications, such as nano-sized sensors, piezotronics, and energy harvesting in portable electronic devices.

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

    SciTech Connect (OSTI)

    Gessert, T. A.

    2010-09-01

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

  7. Pressure-induced Phase Transition in Thiol-capped CdTe Nanoparticles

    SciTech Connect (OSTI)

    Wu, F; Zaug, J; Young, C; Zhang, J Z

    2006-11-29

    Phase transitions for CdTe nanoparticles (NPs) under high pressure up to 37.0 GPa have been studied using fluorescence measurements. The phase transition from cinnarbar to rocksalt phase has been observed in CdTe NPs solution at 5.8 GPa, which is much higher than the phase transition pressure of bulk CdTe (3.8 GPa) and that of CdTe NPs in solid form (0.8 GPa). CdTe NPs solution therefore shows elevated phase transition pressure and enhanced stability against pressure compared with bulk CdTe and CdTe NPs in solid forms. The enhanced stability of CdTe NPs solution has been attributed to possible shape change in the phase transition and/or inhomogeneous strains in nanoparticle solutions.

  8. Nanoscale Imaging of Photocurrent 2 and Efficiency in CdTe Solar...

    Office of Scientific and Technical Information (OSTI)

    Nanoscale Imaging of Photocurrent 2 and Efficiency in CdTe Solar Cells. Citation Details In-Document Search Title: Nanoscale Imaging of Photocurrent 2 and Efficiency in CdTe Solar...

  9. CdTe Thin Film Solar Cells and Modules Tutorial; NREL (National Renewable Energy Laboratory)

    SciTech Connect (OSTI)

    Albin, David S.

    2015-06-13

    This is a tutorial presented at the 42nd IEEE Photovoltaics Specialists Conference to cover the introduction, background, and updates on CdTe cell and module technology, including CdTe cell and module structure and fabrication.

  10. Indication of Te segregation in laser-irradiated ZnTe observed by in situ coherent-phonon spectroscopy

    SciTech Connect (OSTI)

    Shimada, Toru [Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin (Germany); Hirosaki University, 1 Bunkyo-cho, Hirosaki, Aomori 036-8152 (Japan); Kamaraju, N., E-mail: nkamaraju@lanl.gov [Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin (Germany); Los Alamos National Laboratory, Center for Integrated Nanotechnologies, Los Alamos, New Mexico 87545 (United States); Frischkorn, Christian [Department of Physics, Free University of Berlin, Arnimallee 14, 14195 Berlin (Germany); Wolf, Martin; Kampfrath, Tobias [Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin (Germany)

    2014-09-15

    We irradiate a ZnTe single crystal with 10-fs laser pulses at a repetition rate of 80?MHz and investigate its resulting gradual modification by means of coherent-phonon spectroscopy. We observe the emergence of a phonon mode at about 3.6?THz whose amplitude and lifetime grow monotonously with irradiation time. The speed of this process depends sensitively on the pump-pulse duration. Our observations strongly indicate that the emerging phonon mode arises from a Te phase induced by multiphoton absorption of incident laser pulses. A potential application of our findings is laser-machining of microstructures in the bulk of a ZnTe crystal, a highly relevant electrooptic material.

  11. DISSERTATION ELECTRON-REFLECTOR STRATEGY FOR CdTe THIN-FILM SOLAR CELLS

    E-Print Network [OSTI]

    Sites, James R.

    DISSERTATION ELECTRON-REFLECTOR STRATEGY FOR CdTe THIN-FILM SOLAR CELLS Submitted by Kuo-Jui Hsiao ELECTRON- REFLECTOR STRATEGY FOR CdTe THIN-FILM SOLAR CELLS BE ACCEPTED AS FULFILLING IN PART REQUIREMENTS-FILM SOLAR CELLS The CdTe thin-film solar cell has a large absorption coefficient and high theoretical

  12. Solar Energy Materials & Solar Cells 91 (2007) 13881391 Bifacial configurations for CdTe solar cells

    E-Print Network [OSTI]

    Romeo, Alessandro

    2007-01-01

    Solar Energy Materials & Solar Cells 91 (2007) 1388­1391 Bifacial configurations for CdTe solar We present a different back contact for CdTe solar cell by the application of only a transparent that acts as a free-Cu stable back contact and at the same time allows to realize bifacial CdTe solar cells

  13. Carbon Sequestration in Terrestrial Ecosystems (CSiTE) PRINCIPAL INVESTIGATOR: Stan D. Wullschleger

    E-Print Network [OSTI]

    Carbon Sequestration in Terrestrial Ecosystems (CSiTE) PRINCIPAL INVESTIGATOR: Stan D. Wullschleger://csite.eds.ornl.gov PROJECT DESCRIPTION The Carbon Sequestration in Terrestrial Ecosystems (CSiTE) project conducts research of switchgrass growing in the field. #12;Carbon Sequestration in Terrestrial Ecosystems (CSiTE) tion of inputs

  14. Exploring the Potential for High-Quality Epitaxial CdTe Solar Cells , Ana Kanevce2

    E-Print Network [OSTI]

    Sites, James R.

    Exploring the Potential for High-Quality Epitaxial CdTe Solar Cells Tao Song1 , Ana Kanevce2Te solar cell performance is limited by recombination at the grain boundaries, low carrier density (p is not strongly affected until b exceeds 0.4 eV. Index Terms -- device modeling, solar cells, epitaxial CdTe. I

  15. Excited-State Relaxation in PbSe Quantum Dots

    SciTech Connect (OSTI)

    An, J. M.; Califano, M.; Franceschetti, A.; Zunger, A.

    2008-01-01

    In solids the phonon-assisted, nonradiative decay from high-energy electronic excited states to low-energy electronic excited states is picosecond fast. It was hoped that electron and hole relaxation could be slowed down in quantum dots, due to the unavailability of phonons energy matched to the large energy-level spacings ('phonon-bottleneck'). However, excited-state relaxation was observed to be rather fast ({le}1 ps) in InP, CdSe, and ZnO dots, and explained by an efficient Auger mechanism, whereby the excess energy of electrons is nonradiatively transferred to holes, which can then rapidly decay by phonon emission, by virtue of the densely spaced valence-band levels. The recent emergence of PbSe as a novel quantum-dot material has rekindled the hope for a slow down of excited-state relaxation because hole relaxation was deemed to be ineffective on account of the widely spaced hole levels. The assumption of sparse hole energy levels in PbSe was based on an effective-mass argument based on the light effective mass of the hole. Surprisingly, fast intraband relaxation times of 1-7 ps were observed in PbSe quantum dots and have been considered contradictory with the Auger cooling mechanism because of the assumed sparsity of the hole energy levels. Our pseudopotential calculations, however, do not support the scenario of sparse hole levels in PbSe: Because of the existence of three valence-band maxima in the bulk PbSe band structure, hole energy levels are densely spaced, in contradiction with simple effective-mass models. The remaining question is whether the Auger decay channel is sufficiently fast to account for the fast intraband relaxation. Using the atomistic pseudopotential wave functions of Pb{sub 2046}Se{sub 2117} and Pb{sub 260}Se{sub 249} quantum dots, we explicitly calculated the electron-hole Coulomb integrals and the P {yields} S electron Auger relaxation rate. We find that the Auger mechanism can explain the experimentally observed P {yields} S intraband decay time scale without the need to invoke any exotic relaxation mechanisms.

  16. Correlation Between Bands Structure and Magneto-Transport Properties in n-type HgTe/CdTe Superlattice with Relatively Thin CdTe Barrier

    SciTech Connect (OSTI)

    Braigue, M.; Nafidi, A.; Chaib, H.; Tirbiyine, A.; Hemine, J.; Idbaha, A.; Boulkassim, A.; El Gouti, T.; Massaq, M. [Laboratory of Condensed Matter Physics and Nanomaterials for Renewable Energy, Department of Physics, Faculty of Sciences, BP 8106 Hay Dakhla (Morocco); University Ibn Zohr, 80000 Agadir (Morocco); Talwar, Devki N. [Physics Department, Indiana University of Pennsylvania, 975 Oakland Avenue, Indiana, PA 15705 (United States); SrinivasaVinod, M. [Mechanical Engineering Department, RV College of Engineering, Bangalore - 560 059 (India)

    2011-12-26

    Theoretical calculations of the electronic properties of n-type HgTe/CdTe superlattices (SLs) in the envelope function formalism have provided a reasonable agreement with the experimental data on the magneto-transport behavior. Numerical results of the band energies E(d{sub 2}), E(k{sub z}) and E(k{sub p}) in the direction of growth and in plane of the SLs predict that the system retains semiconductor characteristics for d{sub 1}/d{sub 2} = 2.69 and d{sub 2}<10 nm. For d{sub 2} = 3.2 nm the calculated effective band gap (E{sub g}({Gamma},4.2 K) = 48 meV) suggests that the material sample is a two-dimensional modulated nanostructure and a potential candidate to be used for the far infrared detection applications.

  17. School of Mathematical and Computing Sciences Te Kura Pangarau, Rorohiko

    E-Print Network [OSTI]

    Visser, Matt

    waves propagating in a flowing fluid can be described by a wave equation on an "acoustic geometry in the acoustic analogue of gravity MattVisser #12;School of Mathematical and Computing Sciences Te Kura Pangarau an "acoustic geometry" that is qualitatively similar to the equatorial plane of a rotating Kerr black hole

  18. TE Approaches and Experience March 27, 2015 1

    E-Print Network [OSTI]

    and control mechanisms together to balance an electric power system using distributed agent based PNNL-SA-109083 #12;Outline Background and definitions Examples of TE systems Modeling Systems Double auction market PNNL ­ GridWise Olympic Peninsula Demonstration TNO PowerMatcher1 PNNL

  19. TeV Particle Astrophysics II: Summary comments

    E-Print Network [OSTI]

    Thomas K. Gaisser

    2006-12-11

    A unifying theme of this conference was the use of different approaches to understand astrophysical sources of energetic particles in the TeV range and above. In this summary I review how gamma-ray astronomy, neutrino astronomy and (to some extent) gravitational wave astronomy provide complementary avenues to understanding the origin and role of high-energy particles in energetic astrophysical sources.

  20. New QCD results from NuTeV

    SciTech Connect (OSTI)

    M. Tzanov et al.

    2003-09-18

    Preliminary results from next-to-leading order strange sea fits to the NuTeV's deep inelastic scattering charged-current dimuon cross section data are presented. Preliminary neutrino and antineutrino inclusive charged-current differential cross sections and preliminary structure function F{sub 2}(x, Q{sup 2}) are presented.

  1. HTML and LaTeX MATT CHARNLEY

    E-Print Network [OSTI]

    HTML and LaTeX Workshop MATT CHARNLEY BECKY COULSON #12;HTML Outline Writing html code Uploading html to the internet Changing formatting: CSS #12;How to Write HTML Can be written in any plain text editor. Notepad is my go-to, but a lot of other things will work as well. Save documents as .html files

  2. Tantalum Solid Electrolytic Capacitors/TE TESeries: Type : T

    E-Print Network [OSTI]

    Berns, Hans-Gerd

    Tantalum Solid Electrolytic Capacitors/TE TESeries: Type : T -55 to +125°C 4 to 35 V .DC 0.1 to 330.3 1.3 EIA code 3216 3528 6032 5846 7343 W.V. code W.V. (V) code #12;Tantalum Solid Electrolytic

  3. Aspects of jets at 100 TeV

    E-Print Network [OSTI]

    Thaler, Jesse

    We present three case studies at a 100 TeV proton collider for how jet analyses can be improved using new jet (sub)structure techniques. First, we use the winner-take-all recombination scheme to define a recoil-free jet ...

  4. se de doctorat en informatique Comprendre le Web cach

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    niveau à l'aide de telles descriptions. Abstract e hidden Web (also known as deep or invisible Web'informations, complexité Keywords: hidden Web, deep Web, databases, information extraction, complexity tel-00198150,versionèse de doctorat en informatique Comprendre le Web caché Understanding the Hidden Web Pierre

  5. MINIREVIEW / MINISYNTHE` SE The role of chromatin structure in regulating

    E-Print Network [OSTI]

    Krebs, Jocelyn E.

    within many stress-induced promoters, such as stress re- sponse elements and heat shock elements, allow. Key words: chromatin, transcription, stress response, heat shock. Re´sume´ : Toutes les cellules, quMINIREVIEW / MINISYNTHE` SE The role of chromatin structure in regulating stress

  6. ctualmente se afronta una im-portante prdida de biodiversi-

    E-Print Network [OSTI]

    Figuerola, Jordi

    a los medios de comunicación y sean cada vez más tratadas en la prensa científica, no son un fenómeno enfermedades con nuestras actividades por encima del nivel que se daba en siglos ante- riores. Por último y percepción pública sobre la necesidad de conservar el medio natural (¿no sería mejor ma- tar a todos los

  7. www.medicine.gu.se Minnesanteckningar Forskarutbildningsutskottet, inst. fr medicin

    E-Print Network [OSTI]

    www.medicine.gu.se Minnesanteckningar ­ Forskarutbildningsutskottet, inst. för medicin 2015, forskare vid avd. för molekylär och klinisk medicin hälsas välkommen som ny ledamot i FUU. Pauline ersätter informerade om hur antagningarna granskas vid avd. för molekylär och klinisk medicin. De vanligaste bristerna

  8. Transformation toughening in an antiferroelectric ceramic *, S.E. Younga

    E-Print Network [OSTI]

    Hong, Wei

    1 Transformation toughening in an antiferroelectric ceramic X. Tana, *, S.E. Younga , Y.H. Seob , J of the crystal symmetry, dielectric constant, field-induced polarization, and Raman spectrum on ceramic Pb0.99Nb0 is demonstrated in the antiferroelectric ceramic with both indentation fracture and R-curve experiments

  9. 2030 SE Marine Science Drive Newport, Oregon 973665-5296

    E-Print Network [OSTI]

    Wright, Dawn Jeannine

    2030 SE Marine Science Drive Newport, Oregon 973665-5296 Telephone 541-867-0100 Fax 541-867-0138 Web Page http://hmsc.oregonstate.edu Oregon State University Hatfield Marine Science Center 2006.....................................2 Coastal Oregon Marine Experiment Station...........................2 OSU-COMES Seafood Research

  10. Local Charge Neutrality Condition, Fermi Level, and Carrier Compensation of CdTe Polycrystalline Thin Film in CdS/CdTe Solar Cells

    E-Print Network [OSTI]

    Thin Film in CdS/CdTe Solar Cells Ken K. Chin1 and Su-Huai Wei 2 1 Department of Physics and Apollo Cd vacancies VCd (o/-) and VCd (-/2-) in CdTe thin film), the general formulation of charge neutrality-level and multi-configuration intrinsic/impurity defect states for understanding the performance of CdTe thin film

  11. Weak antilocalization effect in LPE-grown p-Hg0.8Cd0.2Te thin film and the evidence of Te-precipitation

    E-Print Network [OSTI]

    R. Yang; L. M. Wei; G. L. Yu

    2010-06-07

    The weak antilocalization effect is observed in a p-type Hg0.8Cd0.2Te thin film with thickness ~10 micrometers. Based on the analysis of composition, carrier species and excellent fitting of data with a model concerning weak antilocalization effect in Te crystal, the most plausible explanation is that the observed weak antilocalization effect is caused by Te-precipitation.

  12. Straightforward Route to the Adamantane Clusters [Sn4Q10]4-(Q ) S, Se, Te) and Use in the Assembly of Open-Framework Chalcogenides

    E-Print Network [OSTI]

    Trikalitis, Pantelis N.

    . For example, in a recent publication it was demonstrated that high surface area porous chalcogenide aerogels

  13. Grain boundary junctions of FeSe0.5Te0.5 thin films on SrTiO3...

    Office of Scientific and Technical Information (OSTI)

    Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA National High Magnetic Field Laboratory, Florida State University,...

  14. HIGH SPATIAL-RESOLUTION IMAGING OF TE INCLUSIONS IN CZT MATERIAL.

    SciTech Connect (OSTI)

    CAMARDA, G.S.; BOLOTNIKOV, A.E.; CARINI, G.A.; CUI, Y.; KOHMAN, K.T.; LI, L.; JAMES, R.B.

    2006-08-13

    We present new results from our studies of defects in current single-crystal CdZnTe material. Our previous measurements, carried out on thin ({approx}1 mm) and long (>12 mm) CZT detectors, indicated that small (1-20 {micro}m) Te inclusions can significantly degrade the device's energy resolution and detection efficiency. We are conducting detailed studies of the effects of Te inclusions by employing different characterization techniques with better spatial resolution, such as quantitative fluorescence mapping, X-ray micro-diffraction, and TEM. Also, IR microscopy and gamma-mapping with pulse-shape analysis with higher spatial resolution generated more accurate results in the areas surrounding the micro-defects (Te inclusions). Our results reveal how the performance of CdZnTe detectors is influenced by Te inclusions, such as their spatial distribution, concentration, and size. We also discuss a model of charge transport through areas populated with Te inclusions.

  15. Surfactant-Free Synthesis of Bi?Te?-Te Micro-Nano Heterostructure with Enhanced Thermoelectric Figure of Merit

    SciTech Connect (OSTI)

    Zhang, Yichi; Wang, Heng; Kraemer, Stephan; Shi, Yifeng; Zhang, Fan; Snedaker, Matt; Ding, Kunlun; Moskovits, Martin; Snyder, G. Jeffrey; Stucky, Galen D.

    2011-01-01

    An ideal thermoelectric material would be a semiconductor with high electrical conductivity and relatively low thermal conductivity: an “electron crystal, phonon glass”. Introducing nanoscale heterostructures into the bulk TE matrix is one way of achieving this intuitively anomalous electron/phonon transport behavior. The heterostructured interfaces are expected to play a significant role in phonon scattering to reduce thermal conductivity and in the energy-dependent scattering of electrical carriers to improve the Seebeck coefficient. A nanoparticle building block assembly approach is plausible to fabricate three-dimensional heterostructured materials on a bulk commercial scale. However, a key problem in applying this strategy is the possible negative impact on TE performance of organic residue from the nanoparticle capping ligands. Herein, we report a wet chemical, surfactant-free, low-temperature, and easily up-scalable strategy for the synthesis of nanoscale heterophase Bi?Te?-Te via a galvanic replacement reaction. The micro-nano heterostructured material is fabricated bottom-up, by mixing the heterophase with commercial Bi?Te?. This unique structure shows an enhanced zT value of ~0.4 at room temperature. This heterostructure has one of the highest figures of merit among bismuth telluride systems yet achieved by a wet chemical bottom-up assembly. In addition, it shows a 40% enhancement of the figure of merit over our lab-made material without nanoscale heterostructures. This enhancement is mainly due to the decrease in the thermal conductivity while maintaining the power factor. Overall, this cost-efficient and room-temperature synthesis methodology provides the potential for further improvement and large-scale thermoelectric applications.

  16. Quantum confined acceptors and donors in InSe nanosheets

    SciTech Connect (OSTI)

    Mudd, G. W.; Patanè, A. Makarovsky, O.; Eaves, L.; Kudrynskyi, Z. R.; Kovalyuk, Z. D.; Fay, M. W.; Zólyomi, V.; Falko, V.

    2014-12-01

    We report on the radiative recombination of photo-excited carriers bound at native donors and acceptors in exfoliated nanoflakes of nominally undoped rhombohedral ?-polytype InSe. The binding energies of these states are found to increase with the decrease in flake thickness, L. We model their dependence on L using a two-dimensional hydrogenic model for impurities and show that they are strongly sensitive to the position of the impurities within the nanolayer.

  17. Does MoSE cope with inland tsunamis hazard?

    E-Print Network [OSTI]

    Panza, Giuliano Francesco; Romanelli, Fabio

    2014-01-01

    In this work we use morphostructural zonation and pattern recognition techniques to identify a potential seismic source located inland very near Venice, and then we evaluate how a tsunami wave generated from this source can affect the MoSE gates if they are standing up (closed) during the tsunami event. From our simulation we get both peaks and troughs as first arrivals: the behavior of the barriers in these two situations could be a very important design matter.

  18. Perlick: Order (2013-SE-14001) | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested PartiesBuilding energy codes havePUBLICofPatriciaOrder (2013-SE-14001)

  19. Perlick: Proposed Penalty (2013-SE-14001) | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested PartiesBuilding energy codes havePUBLICofPatriciaOrder (2013-SE-14001)Proposed

  20. Metal contacts on ZnSe and GaN

    SciTech Connect (OSTI)

    Duxstad, K J [Univ. of California, Berkeley, CA (United States). Materials Science and Mineral Engineering

    1997-05-01

    Recently, considerable interest has been focused on the development of blue light emitting materials and devices. The focus has been on GaN and ZnSe, direct band gap semiconductors with bands gaps of 3.4 and 2.6 eV, respectively. To have efficient, reliable devices it is necessary to have thermally and electrically stable Ohmic contacts. This requires knowledge of the metal-semiconductor reaction behavior. To date few studies have investigated this behavior. Much information has accumulated over the years on the behavior of metals on Si and GaAs. This thesis provides new knowledge for the more ionic wide band gap semiconductors. The initial reaction temperatures, first phases formed, and phase stability of Pt, Pd, and Ni on both semiconductors were investigated. The reactions of these metals on ZnSe and GaN are discussed in detail and correlated with predicted behavior. In addition, comparisons are made between these highly ionic semiconductors and Si and GaAs. The trends observed here should also be applicable to other II-VI and III-Nitride semiconductor systems, while the information on phase formation and stability should be useful in the development of contacts for ZnSe and GaN devices.

  1. High-Efficiency CdTe and CIGS Thin-Film Solar Cells: Highlights and Challenges; Preprint

    SciTech Connect (OSTI)

    Noufi, R.; Zweibel, K.

    2006-05-01

    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.

  2. APdCu(Se2)(Se3) (A ) K and Rb): New Quaternary Copper Palladium Polyselenides with Unusual Metal-Selenium Coordination

    E-Print Network [OSTI]

    Li, Jing

    APdCu(Se2)(Se3) (A ) K and Rb): New Quaternary Copper Palladium Polyselenides with Unusual Metal structurally characterized quaternary copper palladium polychalcogenides with a (Se2)2- and a (Se3)2- fragment ) K and Rb), which are the first quaternary copper palladium polychalcogenides obtained

  3. Evidence for TeV Emission from GRB 970417a

    E-Print Network [OSTI]

    The Milagro Collaboration; R. Atkins; W. Benbow; D. Berley; M. L. Chen; D. G. Coyne; B. L. Dingus; D. E. Dorfan; R. W. Ellsworth; D. Evans; A. Falcone; L. Fleysher; R. Fleysher; G. Gisler; J. A. Goodman; T. J. Haines; C. M. Hoffman; S. Hugenberger; L. A. Kelley; I. Leonor; M. McConnell; J. F. McCullough; J. E. McEnery; R. S. Miller; A. I. Mincer; M. F. Morales; P. Nemethy; J. M. Ryan; B. Shen; A. Shoup; C. Sinnis; A. J. Smith; G. W. Sullivan; T. Tumer; K. Wang; M. O. Wascko; S. Westerhoff; D. A. Williams; T. Yang; G. B. Yodh

    2000-01-07

    Milagrito, a detector sensitive to very high energy gamma rays, monitored the northern sky from February 1997 through May 1998. With a large field of view and a high duty cycle, this instrument was well suited to perform a search for TeV gamma-ray bursts (GRBs). We report on a search made for TeV counterparts to GRBs observed by BATSE. BATSE detected 54 GRBs within the field of view of Milagrito during this period. An excess of events coincident in time and space with one of these bursts, GRB 970417a, was observed by Milagrito. The excess has a chance probability of $2.8 \\times 10^{-5}$ of being a fluctuation of the background. The probability for observing an excess at least this large from any of the 54 bursts is $1.5 \\times 10^{-3}$. No significant correlations were detected from the other bursts.

  4. Evidence for TeV Emission from GRB 970417a

    E-Print Network [OSTI]

    Atkins, R; Berley, D; Chen, M L; Coyne, D G; Dingus, B L; Dorfan, D E; Ellsworth, R W; Evans, D; Falcone, A D; Fleysher, L; Fleysher, R; Gisler, G; Goodman, J A; Haines, T J; Hoffman, C M; Hugenberger, S; Kelley, L A; Leonor, I; McConnell, M; McCullough, J F; McEnery, J E; Miller, R S; Mincer, A I; Morales, M F; Némethy, P; Ryan, J M; Shen, B; Shoup, A L; Sinnis, C; Smith, A J; Sullivan, G W; Tümer, T O; Wang, K; Wascko, M O; Westerhoff, S; Williams, D A; Yang, T; Yodh, G B

    2000-01-01

    Milagrito, a detector sensitive to very high energy gamma rays, monitored the northern sky from February 1997 through May 1998. With a large field of view and a high duty cycle, this instrument was well suited to perform a search for TeV gamma-ray bursts (GRBs). We report on a search made for TeV counterparts to GRBs observed by BATSE. BATSE detected 54 GRBs within the field of view of Milagrito during this period. An excess of events coincident in time and space with one of these bursts, GRB 970417a, was observed by Milagrito. The excess has a chance probability of $2.8 \\times 10^{-5}$ of being a fluctuation of the background. The probability for observing an excess at least this large from any of the 54 bursts is $1.5 \\times 10^{-3}$. No significant correlations were detected from the other bursts.

  5. 2TeV Higgs boson and ATLAS diboson excess

    E-Print Network [OSTI]

    Chen, Chuan-Hung

    2015-01-01

    Diboson resonance with mass around 2 TeV in the dijet invariant mass spectrum is reported by ATLAS experiment in proton-proton collisions at $\\sqrt{s}=8$ TeV. We propose that the candidate of resonance is a heavy neutral Higgs $H^0$ or charged Higgs $H^\\pm$ and use the extended two-Higgs-doublet (THD) to demonstrate the potentiality. We find that the large Yukawa coupling to the first generation of quarks can be realized in THD and the required value for producing the right resonance production cross section is of ${\\cal O}(0.06-0.2)$. Besides $WW/ZZ$ channels, we find that if the mass of pseudoscalar $A^0$ satisfies the jet mass tagging condition $|m_j - m_{Z/W}|< 13$ GeV, the diboson excess could be also caused by $ZA^0$ or $WA^0$ channel.

  6. Milagrito Detection of TeV Emission from Mrk 501

    E-Print Network [OSTI]

    R. Atkins; W. Benbow; D. Berley; M. -L. Chen; D. G. Coyne; R. S. Delay; B. L. Dingus; D. E. Dorfan; R. W. Ellsworth; D. Evans; A. Falcone; L. Fleysher; R. Fleysher; G. Gisler; J. A. Goodman; T. J. Haines; C. M. Hoffman; S. Hugenberger; L. A. Kelley; I. Leonor; J. Macri; M. McConnell; J. F. McCullough; J. E. McEnery; R. S. Miller; A. I. Mincer; M. F. Morales; P. Nemethy; J. M. Ryan; M. Schneider; B. Shen; A. Shoup; G. Sinnis; A. J. Smith; G. W. Sullivan; T. N. Thompson; O. T. Tumer; K. Wang; M. O. Wascko; S. Westerhoff; D. A. Williams; T. Yang; G. B. Yodh

    1999-06-24

    The Milagro water Cherenkov detector near Los Alamos, New Mexico, has been operated as a sky monitor at energies of a few TeV between February 1997 and April 1998. Serving as a test run for the full Milagro detector, Milagrito has taken data during the strong and long-lasting 1997 flare of Mrk 501. We present results from the analysis of Mrk 501 and compare the excess and background rates with expectations from the detector simulations.

  7. Milagrito Detection of TeV Emission from Mrk 501

    E-Print Network [OSTI]

    Atkins, R; Berley, D; Chen, M L; Coyne, D G; Delay, R S; Dingus, B L; Dorfan, D E; Ellsworth, R W; Evans, D; Falcone, A D; Fleysher, L; Fleysher, R; Gisler, G; Goodman, J A; Haines, T J; Hoffman, C M; Hugenberger, S; Kelley, L A; Leonor, I; Macri, J R; McConnell, M; McCullough, J F; McEnery, J E; Miller, R S; Mincer, A I; Morales, M F; Némethy, P; Ryan, J M; Schneider, M; Shen, B; Shoup, A L; Sinnis, G; Smith, A J; Sullivan, G W; Thompson, T N; Tümer, T O; Wang, K; Wascko, M O; Westerhoff, S; Williams, D A; Yang, T; Yodh, G B

    1999-01-01

    The Milagro water Cherenkov detector near Los Alamos, New Mexico, has been operated as a sky monitor at energies of a few TeV between February 1997 and April 1998. Serving as a test run for the full Milagro detector, Milagrito has taken data during the strong and long-lasting 1997 flare of Mrk 501. We present results from the analysis of Mrk 501 and compare the excess and background rates with expectations from the detector simulations.

  8. 2 TeV Walking Technirho at LHC?

    E-Print Network [OSTI]

    Hidenori S. Fukano; Masafumi Kurachi; Shinya Matsuzaki; Koji Terashi; Koichi Yamawaki

    2015-09-12

    The ATLAS collaboration has recently reported an excess of about 2.5 $\\sigma$ global significance at around 2 TeV in the diboson channel with the boson-tagged fat dijets, which may imply a new resonance beyond the standard model. We provide a possible explanation of the excess as the isospin-triplet technivector mesons (technirhos, denoted as $\\rho_\\Pi^{\\pm,3}$) of the walking technicolor in the case of the one-family model as a benchmark. As the effective theory for the walking technicolor at the scales relevant to the LHC experiment, we take a scale-invariant version of the hidden local symmetry model so constructed as to accommodate technipions, technivector mesons, and the technidilaton in such a way that the model respects spontaneously broken chiral and scale symmetries of the underlying walking technicolor. In particular, the technidilaton, a (pseudo) Nambu-Goldstone boson of the (approximate) scale symmetry predicted in the walking technicolor, has been shown to be successfully identified with the 125 GeV Higgs. Currently available LHC limits on those technihadrons are used to fix the couplings of technivector mesons to the standard-model fermions and weak gauge bosons. We find that the technirho's are mainly produced through the Drell-Yan process and predominantly decay to the dibosons, which accounts for the currently reported excess at around 2 TeV. The consistency with the electroweak precision test and other possible discovery channels of the 2 TeV technirhos are also addressed.

  9. Diameter dependent thermoelectric properties of individual SnTe nanowires

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Xu, E. Z.; Li, Z.; Martinez, J. A.; Sinitsyn, N.; Htoon, H.; Li, Nan; Swartzentruber, B.; Hollingsworth, J. A.; Wang, Jian; Zhang, S. X.

    2015-01-15

    The lead-free compound tin telluride (SnTe) has recently been suggested to be a potentially promising thermoelectric material because of its similar electronic band structure as the well-known lead telluride. Here we report on the first thermoelectric study of individual single crystalline SnTe nanowires (NWs) with different diameters ranging from ~200 to ~1000 nm. Measurements of thermopower S, electrical conductivity ?, and thermal conductivity ? were carried out on the same nanowires over a temperature range of 25 - 300 K. While ? does not show a strong diameter dependence, the thermopower increases by a factor of 2 when the nanowiremore »diameter is decreased from 1000 nm to 200 nm. The thermal conductivities of the measured NWs are only about half of that of the bulk SnTe, which may arise from the enhanced phonon-grain boundary and phonon-defect scatterings. Temperature dependent figure-of-merit ZT was determined and the maximum value at room temperature is ~3 times higher than what was obtained in bulk samples of comparable carrier density.« less

  10. Bi-Se doped with Cu, p-type semiconductor

    DOE Patents [OSTI]

    Bhattacharya, Raghu Nath; Phok, Sovannary; Parilla, Philip Anthony

    2013-08-20

    A Bi--Se doped with Cu, p-type semiconductor, preferably used as an absorber material in a photovoltaic device. Preferably the semiconductor has at least 20 molar percent Cu. In a preferred embodiment, the semiconductor comprises at least 28 molar percent of Cu. In one embodiment, the semiconductor comprises a molar percentage of Cu and Bi whereby the molar percentage of Cu divided by the molar percentage of Bi is greater than 1.2. In a preferred embodiment, the semiconductor is manufactured as a thin film having a thickness less than 600 nm.

  11. Sunshine Lighting: Order (2014-SE-54008) | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LIST OF APPLICABLEStatutory Authority forPerk | DepartmentOrder (2014-SE-54008)

  12. Victory: Order (2015-SE-42033) | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LIST OF APPLICABLEStatutoryinEnable LowNewsEnergyOrder (2015-SE-42033) Victory:

  13. Victory: Proposed Penalty (2015-SE-42033) | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LIST OF APPLICABLEStatutoryinEnable LowNewsEnergyOrder (2015-SE-42033)

  14. Post-Growth Annealing of Bridgman-grown CdZnTe and CdMnTe Crystals for Room-temperature Nuclear Radiation Detectors

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Egarievwe, Stephen U.; Yang, Ge; Egarievwe, Alexander; Okwechime, Ifechukwude O.; Gray, Justin; Hales, Zaveon M.; Hossain, Anwar; Camarda, Guiseppe S.; Bolotnikov, Aleksey E.; James, Ralph B.

    2015-02-11

    Bridgman-grown cadmium zinc telluride (CdZnTe or CZT) and cadmium manganese telluride (CdMnTe or CMT) crystals often have Te inclusions that limit their performances as X-ray- and gamma-ray-detectors. We present here the results of post-growth thermal annealing aimed at reducing and eliminating Te inclusions in them. In a 2D analysis, we observed that the sizes of the Te inclusions declined to 92% during a 60-h annealing of CZT at 510 °C under Cd vapor. Further, tellurium inclusions were eliminated completely in CMT samples annealed at 570 °C in Cd vapor for 26 h, whilst their electrical resistivity fell by an ordermore »of 102. During the temperature-gradient annealing of CMT at 730 °C and an 18 °C/cm temperature gradient for 18 h in a vacuum of 10-5 mbar, we observed the diffusion of Te from the sample, causing a reduction in size of the Te inclusions. For CZT samples annealed at 700 °C in a 10 °C/cm temperature gradient, we observed the migration of Te inclusions from a low-temperature region to a high one at 0.022 ?m/s. During the temperature-gradient annealing of CZT in a vacuum of 10-5 mbar at 570 °C and 30 °C/cm for 18 h, some Te inclusions moved toward the high-temperature side of the wafer, while other inclusions of the same size, i.e., 10 µm in diameter, remained in the same position. These results show that the migration, diffusion, and reaction of Te with Cd in the matrix of CZT- and CMT-wafers are complex phenomena that depend on certain conditions.« less

  15. 1.0 Espa,cos de Banach de se,c"oes de um fibrado vetorial. Definiremos nesta se,c"ao v'arios espa,cos vetoriais de se,c"oes de um fibr*

    E-Print Network [OSTI]

    Tausk, Daniel Victor

    1.0 Espa,cos de Banach de se,c"oes de um fibrado vetorial. Definiremos nesta se,c"ao v'arios espa,cos vetoriais de se,c"oes de um fibr* *ado vetorial sobre uma variedade compacta (possivelmente com bordo). Definiremos normas nestes esp* *a,cos mediante as quais eles se tornar"ao espa,cos de

  16. Charge transfer and mobility enhancement at CdO/SnTe heterointerfaces

    SciTech Connect (OSTI)

    Nishitani, Junichi; Yu, Kin Man; Walukiewicz, Wladek

    2014-09-29

    We report a study of the effects of charge transfer on electrical properties of CdO/SnTe heterostructures. A series of structures with variable SnTe thicknesses were deposited by RF magnetron sputtering. Because of an extreme type III band offset with the valence band edge of SnTe located at 1.5?eV above the conduction band edge of CdO, a large charge transfer is expected at the interface of the CdO/SnTe heterostructure. The electrical properties of the heterostructures are analyzed using a multilayer charge transport model. The analysis indicates a large 4-fold enhancement of the CdO electron mobility at the interface with SnTe. The mobility enhancement is attributed to reduction of the charge center scattering through neutralization of the donor-like defects responsible for the Fermi level pinning at the CdO/SnTe interface.

  17. Empirical correlations between the arrhenius' parameters of impurities' diffusion coefficients in CdTe crystals

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Shcherbak, L.; Kopach, O.; Fochuk, P.; James, R. B.; Bolotnikov, A. E.

    2015-01-21

    Understanding of self- and dopant-diffusion in semiconductor devices is essential to our being able to assure the formation of well-defined doped regions. In this paper, we compare obtained in the literature up to date the Arrhenius’ parameters (D=D0exp(–?Ea/kT)) of point-defect diffusion coefficients and the I-VII groups impurities in CdTe crystals and films. We found that in the diffusion process there was a linear dependence between the pre-exponential factor, D0, and the activation energy, ?Ea, of different species: This was evident in the self-diffusivity and isovalent impurity Hg diffusivity as well as for the dominant IIIA and IVA groups impurities andmore »Chlorine, except for the fast diffusing elements (e.g., Cu and Ag), chalcogens O, S, and Se, halogens I and Br as well as the transit impurities Mn, Co, Fe. As a result, reasons of the lack of correspondence of the data to compensative dependence are discussed.« less

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

    SciTech Connect (OSTI)

    Carmody, M.; Gilmore, A.

    2011-05-01

    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.

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

    SciTech Connect (OSTI)

    Sites, J. R.

    2009-01-01

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

  20. Geometric Tracking Control of a Quadrotor UAV on SE(3)

    E-Print Network [OSTI]

    Lee, Taeyoung; McClamroch, N Harris

    2010-01-01

    This paper provides new results for the tracking control of a quadrotor unmanned aerial vehicle (UAV). The UAV has four input degrees of freedom, namely the magnitudes of the four rotor thrusts, that are used to control the six translational and rotational degrees of freedom, and to achieve asymptotic tracking of four outputs, namely, three position variables for the vehicle center of mass and the direction of one vehicle body-fixed axis. A globally defined model of the quadrotor UAV rigid body dynamics is introduced as a basis for the analysis. A nonlinear tracking controller is developed on the special Euclidean group SE(3) and it is shown to have desirable closed loop properties that are almost global. Several numerical examples, including an example in which the quadrotor recovers from being initially upside down, illustrate the versatility of the controller.

  1. Fluorescence quenching of CdSe quantum dots on graphene

    SciTech Connect (OSTI)

    Guo, Xi Tao; Hua Ni, Zhen, E-mail: zhni@seu.edu.cn; Yan Nan, Hai; Hui Wang, Wen [Department of Physics and Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 211189 (China)] [Department of Physics and Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 211189 (China); Yan Liao, Chun [Physics Department, National Photoelectric Technology and Functional Materials and Application of Science and Technology International Cooperation Base, Northwest University, Xi'an 710069 (China)] [Physics Department, National Photoelectric Technology and Functional Materials and Application of Science and Technology International Cooperation Base, Northwest University, Xi'an 710069 (China); Zhang, Yan; Wei Zhao, Wei [Jiangsu Key Laboratory for Design and Fabrication of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189 (China)] [Jiangsu Key Laboratory for Design and Fabrication of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189 (China)

    2013-11-11

    We studied systematically the fluorescence quenching of CdSe quantum dots (QDs) on graphene and its multilayers, as well as graphene oxide (GO) and reduced graphene oxide (rGO). Raman intensity of QDs was used as a quantitatively measurement of its concentration in order to achieve a reliable quenching factor (QF). It was found that the QF of graphene (?13.1) and its multilayers is much larger than rGO (?4.4), while GO (?1.5) has the lowest quenching efficiency, which suggests that the graphitic structure is an important factor for quenching the fluorescence of QDs. It was also revealed that the QF of graphene is not strongly dependent on its thicknesses.

  2. Scandium resonant impurity level in PbTe

    SciTech Connect (OSTI)

    Skipetrov, E. P. Skipetrova, L. A.; Knotko, A. V.; Slynko, E. I.; Slynko, V. E.

    2014-04-07

    We synthesize a scandium-doped PbTe single-crystal ingot and investigate the phase and the elemental composition as well as galvanomagnetic properties of Pb{sub 1-y}Sc{sub y}Te alloys in weak magnetic fields (4.2?K???T???300?K, B???0.07?T) upon varying the scandium content (y???0.02). We find that all investigated samples are single-phase and n-type. The distribution of scandium impurities along the axis of the ingot is estimated to be exponential. An increase of scandium impurity content leads to a monotonous growth of the free electron concentration by four orders of magnitude (approximately from 10{sup 16}?cm{sup ?3} to 10{sup 20}?cm{sup ?3}). In heavily doped alloys (y?>?0.01), the free electron concentration at the liquid-helium temperature tends to saturation, indicating the pinning of the Fermi energy by the scandium resonant impurity level located on the background of the conduction band. Using the two-band Kane and six-band Dimmock dispersion relations for IV-VI semiconductors, dependences of the Fermi energy measured from the bottom of the conduction band E{sub c} on the scandium impurity content are calculated and the energy of the resonant scandium level is estimated to be E{sub Sc}???E{sub c}?+?280?meV. Diagrams of electronic structure rearrangement of Pb{sub 1-y}Sc{sub y}Te alloys upon doping are proposed.

  3. Supersymmetry Without Prejudice at the 7 TeV LHC

    SciTech Connect (OSTI)

    Conley, John A.; /Bonn U.; Gainer, James S.; /Argonne /Northwestern U.; Hewett, JoAnne L.; Le, My Phuong; Rizzo, Thomas G.; /SLAC

    2011-08-12

    We investigate the model independent nature of the Supersymmetry search strategies at the 7 TeV LHC. To this end, we study the missing-transverse-energy-based searches developed by the ATLAS Collaboration that were essentially designed for mSUGRA. We simulate the signals for {approx} 71k models in the 19-dimensional parameter space of the pMSSM. These models have been found to satisfy existing experimental and theoretical constraints and provide insight into general features of the MSSM without reference to a particular SUSY breaking scenario or any other assumptions at the GUT scale. Using backgrounds generated by ATLAS, we find that imprecise knowledge of these estimated backgrounds is a limiting factor in the potential discovery of these models and that some channels become systematics-limited at larger luminosities. As this systematic error is varied between 20-100%, roughly half to 90% of this model sample is observable with significance S {ge} 5 for 1 fb{sup -1} of integrated luminosity. We then examine the model characteristics for the cases which cannot be discovered and find several contributing factors. We find that a blanket statement that squarks and gluinos are excluded with masses below a specific value cannot be made. We next explore possible modifications to the kinematic cuts in these analyses that may improve the pMSSM model coverage. Lastly, we examine the implications of a null search at the 7 TeV LHC in terms of the degree of fine-tuning that would be present in this model set and for sparticle production at the 500 GeV and 1 TeV Linear Collider.

  4. Electromagnetic leptogenesis at the TeV scale

    E-Print Network [OSTI]

    Debajyoti Choudhury; Namit Mahajan; Sudhanwa Patra; Utpal Sarkar

    2011-04-11

    We construct an explicit model implementing electromagnetic leptogenesis. In a simple extension of the Standard Model, a discrete symmetry forbids the usual decays of the right-handed neutrinos, while allowing for an effective coupling between the left-handed and right-handed neutrinos through the electromagnetic dipole moment. This generates correct leptogenesis with resonant enhancement and also the required neutrino mass via a TeV scale seesaw mechanism. The model is consistent with low energy phenomenology and would have distinct signals in the next generation colliders, and, perhaps even the LHC.

  5. PVA TePla AG | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop Inc Jump to:Newberg,Energy LLC Jump to:3 of Mason County JumpPVA TePla AG Jump to:

  6. Photoluminescence study of the substitution of Cd by Zn during the growth by atomic layer epitaxy of alternate CdSe and ZnSe monolayers

    SciTech Connect (OSTI)

    Hernández-Calderón, I.; Salcedo-Reyes, J. C.

    2014-05-15

    We present a study of the substitution of Cd atoms by Zn atoms during the growth of alternate ZnSe and CdSe compound monolayers (ML) by atomic layer epitaxy (ALE) as a function of substrate temperature. Samples contained two quantum wells (QWs), each one made of alternate CdSe and ZnSe monolayers with total thickness of 12 ML but different growth parameters. The QWs were studied by low temperature photoluminescence (PL) spectroscopy. We show that the Cd content of underlying CdSe layers is affected by the exposure of the quantum well film to the Zn flux during the growth of ZnSe monolayers. The amount of Cd of the quantum well film decreases with higher exposures to the Zn flux. A brief discussion about the difficulties to grow the Zn{sub 0.5}Cd{sub 0.5}Se ordered alloy (CuAu-I type) by ALE is presented.

  7. Improving Energy Efficiency by Developing Components for Distributed Cooling and Heating Based on Thermal Comfort Modeling[Thermoelectric (TE) HVAC

    Broader source: Energy.gov [DOE]

    Discusses results from TE HVAC project to add detail to a human thermal comfort model and further allow load reduction in the climate control energy through a distributed TE network

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

    SciTech Connect (OSTI)

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

    2009-04-01

    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).

  9. Constraints on the TeV source population and its contribution to the galactic diffuse TeV emission

    E-Print Network [OSTI]

    Sabrina Casanova; Brenda L. Dingus

    2007-11-19

    The detection by the HESS atmospheric Cerenkov telescope of fourteen new sources from the Galactic plane makes it possible to estimate the contribution of unresolved sources like those detected by HESS to the diffuse Galactic emission measured by the Milagro Collaboration. The number-intensity relation and the luminosity function for the HESS source population are investigated. By evaluating the contribution of such a source population to the diffuse emission we conclude that a significant fraction of the TeV energy emission measured by the Milagro experiment could be due to unresolved sources like HESS sources. Predictions concerning the number of sources which Veritas, Milagro, and HAWC should detect are also given.

  10. $?$ and $?$ Production in Proton-Proton Collisions at E=13 TeV

    E-Print Network [OSTI]

    Leonard S. Kisslinger; Debasish Das

    2015-05-27

    This article is an extension of our recent studies of $\\Psi$ and $\\Upsilon$ production cross sections in proton-proton collisions at the LHC with E=$\\sqrt{s}$=8.0 TeV to E=13 TeV

  11. Field emission cooling of thermoelectric semiconductor PbTe M. S. Chung,1,a

    E-Print Network [OSTI]

    Mayer, Alexandre

    Field emission cooling of thermoelectric semiconductor PbTe M. S. Chung,1,a A. Mayer,2 B. L. Weiss due to field emission from n-type PbTe, a typical thermoelectric material. We show that, by calculating the average energies of field and replacement electrons, the energy exchange in field emission

  12. TE Challenge Interim meeting Dec 3-4, 2015 Draft Agenda

    E-Print Network [OSTI]

    and Cyber-Physical Systems Program Office and National Coordinator for Smart Grid Interoperability) o DOE perspective (Chris Irwin, Program Manager For TE, Communications And Interoperability In Smart Grid, DOE) o TE area or another (stretch goals). Microgrids Energy Management (Jennifer Worrall) Business

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

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    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

  14. Performance predictions for monolithic, thin-film CdTe/Ge tandem solar cells

    E-Print Network [OSTI]

    Pulfrey, David L.

    Performance predictions for monolithic, thin-film CdTe/Ge tandem solar cells D.L. Pulfrey*, J. Dell): pulfrey@ece.ubc.ca ABSTRACT Cadmium telluride thin-film solar cells are now commercially available be attainable. 1. INTRODUCTION Thin film solar cells based on polycrystalline CdTe have been investigated

  15. Solar Energy Materials & Solar Cells 91 (2007) 13881391 Bifacial configurations for CdTe solar cells

    E-Print Network [OSTI]

    Romeo, Alessandro

    2007-01-01

    Solar Energy Materials & Solar Cells 91 (2007) 1388­1391 Bifacial configurations for CdTe solar Verona, Italy e Department of Electronic and Electrical Engineering, Centre for Renewable Energy Systems We present a different back contact for CdTe solar cell by the application of only a transparent

  16. NUMERICAL MODELING OF CIGS AND CdTe SOLAR CELLS: SETTING THE BASELINE

    E-Print Network [OSTI]

    Sites, James R.

    NUMERICAL MODELING OF CIGS AND CdTe SOLAR CELLS: SETTING THE BASELINE M. Gloeckler, A important complications that are often found in experimental CIGS and CdTe solar cells. 1. INTRODUCTION Numerical modeling of polycrystalline thin-film solar cells is an important strategy to test the viability

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

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    A Search for TeV Emission from Active Galaxies using the Milagro Observatory by Elizabeth A. HaysV Emission from Active Galaxies using the Milagro Observatory Elizabeth A. Hays, Doctor of Philosophy, 2004 the results of two separate searches of the Milagro data for TeV emission. A real-time search of the entire

  18. DISSERTATION Role of the Cu-O Defect in CdTe Solar Cells

    E-Print Network [OSTI]

    Sites, James R.

    DISSERTATION Role of the Cu-O Defect in CdTe Solar Cells Submitted by Caroline R. Corwine OF THE CU-O DEFECT COMPLEX IN CDTE SOLAR CELLS Thin-film CdTe is one of the leading materials used in photovoltaic (PV) solar cells. One way to improve device performance and stability is through understanding how

  19. 1. INTRODUCTION Polycrystalline CdTe thin films solar cells have shown long

    E-Print Network [OSTI]

    Romeo, Alessandro

    to the solar panel that can be adapted to any kind of shape and is easy to deploy in space. We have developed ~12% efficiency (AM1.5) CdTe solar cells on glass substrates with a vacuum deposition process [3 in the "superstrate" or "substrate" configuration (see figure 1). High efficiency CdTe solar cells are generally grown

  20. Thermoelectric Properties Modeling of Bi2Te3 Seungwon Lee and Paul von Allmen

    E-Print Network [OSTI]

    Goddard III, William A.

    Thermoelectric Properties Modeling of Bi2Te3 Seungwon Lee and Paul von Allmen Jet propulsion/23/2005 Overview · Introduce EZTB a modeling tool for thermoelectric properties using a tight-binding model-binding parameters for Bi2Te3. · Present the accuracy of the modeling tool with the thermoelectric properties of Bi2

  1. Extending Higgs Inflation with TeV Scale New Physics

    E-Print Network [OSTI]

    Hong-Jian He; Zhong-Zhi Xianyu

    2014-10-09

    Higgs inflation is among the most economical and predictive inflation models, although the original Higgs inflation requires tuning the Higgs or top mass away from its current experimental value by more than $2\\sigma$ deviations, and generally gives a negligible tensor-to-scalar ratio $r \\sim 10^{-3}$ (if away from the vicinity of critical point). In this work, we construct a minimal extension of Higgs inflation, by adding only two new weak-singlet particles at TeV scale, a vector-quark $T$ and a real scalar $S$. The presence of singlets $(T, S)$ significantly impact the renormalization group running of the Higgs boson self-coupling. With this, our model provides a wider range of the tensor-to-scalar ratio $r = O(0.1 - 10^{-3})$, consistent with the favored $r$ values by either BICEP2 or Planck data, while keeping the successful prediction of the spectral index $ n_s \\simeq 0.96 $. It further allows the Higgs and top masses to fully fit the collider measurements. We also discuss implications for searching the predicted TeV-scale vector-quark $T$ and scalar $S$ at the LHC and future high energy pp colliders.

  2. Purification of CdZnTe by Electromigration

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kim, K.; Kim, Sangsu; Hong, Jinki; Lee, Jinseo; Hong, Taekwon; Bolotnikov, A. E.; Camarda, G. S.; James, R. B.

    2015-04-14

    Electro-migration of ionized/electrically active impurities in CdZnTe (CZT) was successfully demonstrated at elevated temperature with an electric field of 20 V/mm. Copper, which exists in positively charged states, electro-migrated at a speed of 15 lm/h in an electric field of 20 V/mm. A notable variation in impurity concentration along the growth direction with the segregation tendency of the impurities was observed in an electro-migrated CZT boule. Notably, both Ga and Fe, which exist in positively charged states, exhibited the opposite distribution to that of their segregation tendency in Cd(Zn)Te. Furthermore, a CZT detector fabricated from the middle portion of themore »electromigrated CZT boule showed an improved mobility-lifetime product of 0.91 10-2 cm2 /V, compared to that of 1.4 10-3 cm2 /V, observed in an as-grown (non-electro-migrated) CZT detector. The optimum radiation detector material would have minimum concentration of deep traps required for compensation.« less

  3. Extending Higgs inflation with TeV scale new physics

    SciTech Connect (OSTI)

    He, Hong-Jian; Xianyu, Zhong-Zhi E-mail: xianyuzhongzhi@gmail.com

    2014-10-01

    Higgs inflation is among the most economical and predictive inflation models, although the original Higgs inflation requires tuning the Higgs or top mass away from its current experimental value by more than 2? deviations, and generally gives a negligible tensor-to-scalar ratio r ? 10{sup -3} (if away from the vicinity of critical point). In this work, we construct a minimal extension of Higgs inflation, by adding only two new weak-singlet particles at TeV scale, a vector-quark T and a real scalar S. The presence of singlets (T, S) significantly impact the renormalization group running of the Higgs boson self-coupling. With this, our model provides a wider range of the tensor-to-scalar ratio r=O(0.1)-O(10{sup -3}), consistent with the favored r values by either BICEP2 or Planck data, while keeping the successful prediction of the spectral index n{sub s} ? 0.96. It allows the Higgs and top masses to fully fit the collider measurements. We also discuss implications for searching the predicted TeV-scale vector-quark T and scalar S at the LHC and future high energy pp colliders.

  4. Advanced CdTe Photovoltaic Technology: September 2007 - March 2009

    SciTech Connect (OSTI)

    Barth, K.

    2011-05-01

    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.

  5. PROJECT PROFILE: Defining the Defect Chemistry and Structural Properties Required for 24%-Efficient CdTe Devices

    Broader source: Energy.gov [DOE]

    While crystalline silicon accounted for two thirds of the photovoltaic (PV) market in 2014, cadmium telluride (CdTe) PV modules are becoming increasingly competitive with continued improvements in efficiency and reduction in price. This project will enable 24% efficient CdTe cells by improving the defect chemistry and structural properties of polycrystalline cadmium telluride (CdTe) necessary to overcome photovoltage barriers, the main hurdle to higher efficiency of commercial CdTe PV.

  6. Growth of CdTe thin films on graphene by close-spaced sublimation method

    SciTech Connect (OSTI)

    Jung, Younghun; Yang, Gwangseok; Kim, Jihyun, E-mail: hyunhyun7@korea.ac.kr [Department of Chemical and Biological Engineering, Korea University, Seoul 136-701 (Korea, Republic of)] [Department of Chemical and Biological Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Chun, Seungju; Kim, Donghwan [Department of Materials Science and Engineering, Korea University, Seoul 136-701 (Korea, Republic of)] [Department of Materials Science and Engineering, Korea University, Seoul 136-701 (Korea, Republic of)

    2013-12-02

    CdTe thin films grown on bi-layer graphene were demonstrated by using the close-spaced sublimation method, where CdTe was selectively grown on the graphene. The density of the CdTe domains was increased with increasing the number of the defective sites in the graphene, which was controlled by the duration of UV exposure. The CdTe growth rate on the bi-layer graphene electrodes was 400?nm/min with a bandgap energy of 1.45–1.49?eV. Scanning electron microscopy, micro-Raman spectroscopy, micro-photoluminescence, and X-ray diffraction technique were used to confirm the high quality of the CdTe thin films grown on the graphene electrodes.

  7. Growth of HgTe Quantum Wells for IR to THz Detectors S. DVORETSKY,1,3

    E-Print Network [OSTI]

    Ganichev, Sergey

    on this research, high-quality (013)-grown HgTe QW structures can be used for all-electric detection of radiation. Detection was demon- strated for various low-power continuous-wave (CW) lasers and high-power THz pulsed laser systems. Key words: Growth, HgTe, HgCdTe, quantum wells (QWs), ellipsometric parameters, MBE, far

  8. High Efficiency Thin Film CdTe and a-Si Based Solar Cells Annual Technical Report for the Period

    E-Print Network [OSTI]

    Deng, Xunming

    High Efficiency Thin Film CdTe and a-Si Based Solar Cells Annual Technical Report for the Period This report covers the second year 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. The effort on CdTe- based materials

  9. HIGH EFFICIENCY CdTe/CdS THIN FILM SOLAR CELLS WITH A NOVEL BACK-CONTACT Nicola Romeoa

    E-Print Network [OSTI]

    Romeo, Alessandro

    HIGH EFFICIENCY CdTe/CdS THIN FILM SOLAR CELLS WITH A NOVEL BACK-CONTACT Nicola Romeoa , Alessio in the fabrication of high efficiency CdTe/CdS thin film solar cells. Usually, it is done first by etching the CdTe/CdS structure causing shunt paths by segregating into the grain boundaries or lowering the cell efficiency

  10. Intersubband absorption in CdSe/Zn{sub x}Cd{sub y}Mg{sub 1-x-y}Se self-assembled quantum dot multilayers

    SciTech Connect (OSTI)

    Shen, A.; Lu, H.; Charles, W.; Yokomizo, I.; Tamargo, M. C.; Franz, K. J.; Gmachl, C.; Zhang, S. K.; Zhou, X.; Alfano, R. R.; Liu, H. C.

    2007-02-12

    The authors report the observation of intersubband absorption in multilayers of CdSe/Zn{sub x}Cd{sub y}Mg{sub 1-x-y}Se self-assembled quantum dots. The samples were grown by molecular beam epitaxy on InP substrates. For samples with the CdSe dot layers doped with Cl and with the deposited CdSe equivalent layer thickness between 5.2 and 6.9 ML, peak absorption between 2.5 and 3.5 {mu}m was observed. These materials are promising for intersubband devices operating in the mid- and near-infrared ranges.

  11. Power-law solutions for TeVeS

    E-Print Network [OSTI]

    C. E. Magalhaes Batista; W. Zimdahl

    2010-03-18

    The dynamics of TeVeS in a homogeneous and isotropic universe is shown to be equivalent to the dynamics of an interacting two-component system, consisting of a scalar field and a "fluid", related to the matter part, with explicitly given coupling term. Scaling solutions (solutions with a constant ratio of the energy densities of both components) in the "Einstein frame" are found which are exponentially expanding or contracting with no remaining freedom for Bekenstein's $F$ function. In the "physical frame" these solutions are of the power-law type. An equivalent General Relativity (GR) picture of the dynamics suggests that it is the scalar field which plays the role of dark matter, while the "matter" has to mimic (phantom-type) dark energy.

  12. Studies on optoelectronic properties of DC reactive magnetron sputtered CdTe thin films

    SciTech Connect (OSTI)

    Kumar, B. Rajesh, E-mail: rajphyind@gmail.com [Department of Physics, Sri Venkateswara University, Tirupati - 517 502, A.P, India and Department of Physics, Sri Krishnadevaraya University, Anantapur - 515 003, A.P (India); Hymavathi, B.; Rao, T. Subba [Department of Physics, Sri Krishnadevaraya University, Anantapur - 515 003, A.P (India)

    2014-01-28

    Cadmium telluride continues to be a leading candidate for the development of cost effective photovoltaics for terrestrial applications. In the present work two individual metallic targets of Cd and Te were used for the deposition of CdTe thin films on mica substrates from room temperature to 300 °C by DC reactive magnetron sputtering method. XRD patterns of CdTe thin films deposited on mica substrates exhibit peaks at 2? = 27.7°, 46.1° and 54.6°, which corresponds to reflection on (1 1 1), (2 2 0) and (3 1 1) planes of CdTe cubic structure. The intensities of XRD patterns increases with the increase of substrate temperature upto 150 °C and then it decreases at higher substrate temperatures. The conductivity of CdTe thin films measured from four probe method increases with the increase of substrate temperature. The activation energies (?E) are found to be decrease with the increase of substrate temperature. The optical transmittance spectra of CdTe thin films deposited on mica have a clear interference pattern in the longer wavelength region. The films have good transparency (T > 85 %) exhibiting interference pattern in the spectral region between 1200 – 2500 nm. The optical band gap of CdTe thin films are found to be in the range of 1.48 – 1.57. The refractive index, n decreases with the increase of wavelength, ?. The value of n and k increases with the increase of substrate temperature.

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

    SciTech Connect (OSTI)

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

    2012-08-01

    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%.

  14. Search for a TeV Component of GRBs using the Milagrito Detector

    E-Print Network [OSTI]

    R. Atkins; W. Benbow; D. Berley; M. -L. Chen; D. G. Coyne; R. S. Delay; B. L. Dingus; D. E. Dorfan; R. W. Ellsworth; D. Evans; A. Falcone; L. Fleysher; R. Fleysher; G. Gisler; J. A. Goodman; T. J. Haines; C. M. Hoffman; S. Hugenberger; L. A. Kelley; I. Leonor; J. Macri; M. McConnell; J. F. McCullough; J. E. McEnery; R. S. Miller; A. I. Mincer; M. F. Morales; P. Nemethy; J. M. Ryan; M. Schneider; B. Shen; A. Shoup; G. Sinnis; A. J. Smith; G. W. Sullivan; T. N. Thompson; O. T. Tumer; K. Wang; M. O. Wascko; S. Westerhoff; D. A. Williams; T. Yang; G. B. Yodh

    1999-06-24

    Observing gamma ray bursts (GRBs) in the TeV energy range can be extremely valuable in providing insight to GRB radiation mechanisms and in constraining source distances. The Milagrito detector was an air shower array which used the water Cherenkov technique to search for TeV sources. Data from this detector was analyzed to look for a TeV component of GRBs coincident with low energy -rays detected by the BATSE instrument on the Compton Gamma Ray Observatory. A sample of 54 BATSE GRBs which were in the field of view of the Milagrito detector during its lifetime (February 1997 to May 1998) was used.

  15. Search for a TeV Component of GRBs using the Milagrito Detector

    E-Print Network [OSTI]

    Atkins, R; Berley, D; Chen, M L; Coyne, D G; Delay, R S; Dingus, B L; Dorfan, D E; Ellsworth, R W; Evans, D; Falcone, A D; Fleysher, L; Fleysher, R; Gisler, G; Goodman, J A; Haines, T J; Hoffman, C M; Hugenberger, S; Kelley, L A; Leonor, I; Macri, J R; McConnell, M; McCullough, J F; McEnery, J E; Miller, R S; Mincer, A I; Morales, M F; Némethy, P; Ryan, J M; Schneider, M; Shen, B; Shoup, A L; Sinnis, G; Smith, A J; Sullivan, G W; Thompson, T N; Tümer, T O; Wang, K; Wascko, M O; Westerhoff, S; Williams, D A; Yang, T; Yodh, G B

    1999-01-01

    Observing gamma ray bursts (GRBs) in the TeV energy range can be extremely valuable in providing insight to GRB radiation mechanisms and in constraining source distances. The Milagrito detector was an air shower array which used the water Cherenkov technique to search for TeV sources. Data from this detector was analyzed to look for a TeV component of GRBs coincident with low energy -rays detected by the BATSE instrument on the Compton Gamma Ray Observatory. A sample of 54 BATSE GRBs which were in the field of view of the Milagrito detector during its lifetime (February 1997 to May 1998) was used.

  16. Multi-channel Absorption of Photons at Energies above 1 TeV

    E-Print Network [OSTI]

    A. Subramanian

    2006-07-24

    It is shown that the absorption of photons at energies > 1 TeV (much higher than the mass of the Higgs boson ~ 100 GeV) is a multi-channel one as opposed to the purely electron pair like absorption at lower energies. The observation on muons and gamma rays from Cygnus X-3 point source at these energies (1 TeV to 10 TeV) is quantitatively accounted for. The expected multi-channel cross-sections of photons in air as a function of energy is given both for Coulomb dissociation and nuclear absorption upto limiting energies of 10^9 GeV.

  17. Superconductivity in textured Bi clusters/Bi{sub 2}Te{sub 3} films

    SciTech Connect (OSTI)

    Le, Phuoc Huu [Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu 30049, Taiwan (China); Faculty of Basic Sciences, Can Tho University of Medicine and Pharmacy, 179 Nguyen Van Cu Street, Can Tho (Viet Nam); Tzeng, Wen-Yen; Chen, Hsueh-Ju; Luo, Chih Wei, E-mail: cwluo@mail.nctu.edu.tw [Department of Electrophysics, National Chiao Tung University, Hsinchu 300, Taiwan (China); Lin, Jiunn-Yuan [Institute of Physics, National Chiao Tung University, Hsinchu 300, Taiwan (China); Leu, Jihperng, E-mail: jimleu@mail.nctu.edu.tw [Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu 30049, Taiwan (China)

    2014-09-01

    We report superconductivity at an onset critical temperature below 3.1 K in topological insulator ?200-nm-thick Bi{sub 2}Te{sub 3} thin films grown by pulsed laser deposition. Using energy-dispersive X-ray spectroscopy elemental mapping and Auger electron spectroscopy elemental depth profiling, we clearly identified bismuth (Bi) precipitation and Bi cluster signatures. Superconductivity in the Bi{sub 2}Te{sub 3} films was attributed to the proximity effect of Bi clusters precipitated on the surface of the Bi{sub 2}Te{sub 3} films.

  18. Origin of the phase transition in IrTe2: structural modulation and local bonding instability

    SciTech Connect (OSTI)

    Cao, Huibo [ORNL; Chakoumakos, Bryan C [ORNL; Yan, Jiaqiang [ORNL; Zhou, Haidong [ORNL; Custelcean, Radu [ORNL; Mandrus, D. [University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL); McGuire, Michael A [ORNL; Singh, David J [ORNL; Chen, Xin [ORNL; Yang, Hui [University of Tennessee, Knoxville (UTK)

    2013-01-01

    We used X-ray/neutron diffraction to determine the low temperature (LT) structure of IrTe2. A structural modulation was observed with a wavevector of k =(1/5, 0, 1/5) below Ts285 K, accompanied by a structural transition from a trigonal to a triclinic lattice. We also performed the first principles calculations for high temperature (HT) and LT structures, which elucidate the nature of the phase transition and the LT structure. A local bonding instability associated with the Te 5p states is likely the origin of the structural phase transition in IrTe2.

  19. Secretary Chu to Lead Delegation to SE4All, CEM Conferences in...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    to Lead Delegation to SE4All, CEM Conferences in London Secretary Chu to Lead Delegation to SE4All, CEM Conferences in London April 9, 2012 - 10:13am Addthis WASHINGTON, DC - Later...

  20. Sbado 10.11.2012 English | Deutsch | Franais | Italiano | Espaol | Portugus | | | Fazer login | Cadastre-se

    E-Print Network [OSTI]

    Barbosa, Marcia C. B.

    dispararam contra drone dos EUA 09 Novembro, 2012 - 16:57 O sobrinho de George W. Bush, meio hispânico, se

  1. SE2NN11 Neural Networks Part B Dr Richard Mitchell, 2014 1

    E-Print Network [OSTI]

    Mitchell, Richard

    SE2NN11 ­ Neural Networks ­ Part B © Dr Richard Mitchell, 2014 1 p1 RJM 16/09/14 SE2NN11 Neural Networks ­ Part B © Dr Richard Mitchell 2014 SE2NN11 Neural Networks : Part B In Part B of the course, I Networks Including Stochastic Diffusion Search p2 RJM 16/09/14 SE2NN11 Neural Networks ­ Part B © Dr

  2. Energy relaxation in CdSe nanocrystals: the effects of morphology and film preparation

    E-Print Network [OSTI]

    Ruan, Xiulin

    solar cells. harvesting light energy with CdSe nanocrystals molecularly linked to mesoscopic TiO2 filmsEnergy relaxation in CdSe nanocrystals: the effects of morphology and film preparation Bryan T time-resolved absorption spectroscopy is used to investigate exciton dynamics in CdSe nanocrystal films

  3. DISSERTATION ANTICIPATED PERFORMANCE OF Cu(In,Ga)Se2 SOLAR CELLS IN THE

    E-Print Network [OSTI]

    Sites, James R.

    i DISSERTATION ANTICIPATED PERFORMANCE OF Cu(In,Ga)Se2 SOLAR CELLS IN THE THIN-FILM LIMIT Submitted ENTITLED `ANTICIPATED PERFORMANCE OF Cu(In,Ga)Se2 SOLAR CELLS IN THE THIN-FILM LIMIT' BE ACCEPTED(In,Ga)Se2 SOLAR CELLS IN THE THIN-FILM LIMIT The demand for alternative sources of energy is rapidly

  4. Intrinsic Rashba-like splitting in asymmetric Bi{sub 2}Te{sub 3}/Sb{sub 2}Te{sub 3} heterogeneous topological insulator films

    SciTech Connect (OSTI)

    Liu, Xiaofei; Guo, Wanlin

    2014-08-25

    We show by density functional theory calculations that asymmetric hetero-stacking of Bi{sub 2}Te{sub 3}/Sb{sub 2}Te{sub 3} films can modulate the topological surface states. Due to the structure inversion asymmetry, an intrinsic Rashba-like splitting of the conical surface bands is aroused. While such splitting in homogeneous Bi{sub 2}Te{sub 3}-class topological insulators can be realized in films with more than three quintuple layers under external electric fields, the hetero-stacking breaks the limit of thickness for preserving the topological nature into the thinnest two quintuple layers. These results indicate that the hetero-stacking can serve as an efficient strategy for spin-resolved band engineering of topological insulators.

  5. Effects of Ge replacement in GeTe by [Ag+Sb] on thermoelectric...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in GeTe by Ag+Sb on thermoelectric properties and NMR spectra Requirements for student: general physics and chemistry courses, and desire to work in experimental laboratory. This...

  6. First results on neutrinoless double beta decay of Te-130 with the calorimetric cuoricino experiment

    E-Print Network [OSTI]

    2003-01-01

    Results on Neutrinoless Double Beta Decay of 130 Te with theEvidence for Neutrinoless Double Beta Decay” arXiv:hep-on “Evidence for neutrinoless double beta decay”- arXiv:hep-

  7. Atomic-force microscopy and photoluminescence of nanostructured CdTe

    SciTech Connect (OSTI)

    Babentsov, V.; Sizov, F.; Franc, J.; Luchenko, A.; Svezhentsova, E. Tsybrii, Z.

    2013-09-15

    Low-dimensional CdTe nanorods with a diameter of 10-30 nm and a high aspect ratio that reaches 100 are studied. The nanorods are grown by the physical vapor transport method with the use of Bi precipitates on the substrates. In addition, thin films of closely packed CdTe nanorods with the transverse dimensions {approx}(100-200) nm are grown. Atomic-force microscopy shows that the cross sections of all of the nanorods were hexagonally shaped. By photoluminescence measurements, the inference about the wurtzite structure of CdTe is supported, and the structural quality, electron-phonon coupling, and defects are analyzed. On the basis of recent ab initio calculations, the nature of defects responsible for the formation of deep levels in the CdTe layers and bulk crystals are analyzed.

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

    E-Print Network [OSTI]

    Chanowitz, Michael S

    2009-01-01

    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

  9. Data Release for NuTeV nu_e Disappearance Analysis

    E-Print Network [OSTI]

    Conrad, J.M.

    2012-07-23

    Data Release for the NuTeV electron flavor disappearance study. See this document for instructions on incorporating the NuteV nu_e disappearance data into oscillation global fits.

  10. Search for Neutrinoless Double-Beta Decay of [superscript 130]Te with CUORE-0

    E-Print Network [OSTI]

    Alfonso, K.

    We report the results of a search for neutrinoless double-beta decay in a 9.8 kg yr exposure of [superscript 130]Te using a bolometric detector array, CUORE-0. The characteristic detector energy resolution and background ...

  11. Structural analysis of Cr aggregation in ferromagnetic semiconductor (Zn,Cr)Te

    SciTech Connect (OSTI)

    Kobayashi, H.; Yamawaki, K.; Nishio, Y.; Kanazawa, K.; Kuroda, S.; Mitome, M.; Bando, Y.

    2013-12-04

    The Cr aggregation in a ferromagnetic semiconductor (Zn,Cr)Te was studied by performing precise analyses using TEM and XRD of microscopic structure of the Cr-aggregated regions formed in iodine-doped Zn{sub 1?x}Cr{sub x}Te films with a relatively high Cr composition x ? 0.2. It was found that the Cr-aggregated regions are composed of Cr{sub 1??}Te nanocrystals of the hexagonal structure and these hexagonal precipitates are stacked preferentially on the (111)A plane of the zinc-blende (ZB) structure of the host ZnTe crystal with its c-axis nearly parallel to the (111){sub ZB} plane.

  12. Renaissance of the ~1 TeV fixed-target program

    E-Print Network [OSTI]

    Conrad, Janet

    This document describes the physics potential of a new fixed-target program based on a ~1 TeV proton source. Two proton sources are potentially available in the future: the existing Tevatron at Fermilab, which can provide ...

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

    Broader source: Energy.gov (indexed) [DOE]

    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...

  14. Simulation, Modeling, and Crystal Growth of Cd0.9Zn0.1Te for...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Simulation, Modeling, and Crystal Growth of Cd0.9Zn0.1Te for Nuclear Spectrometers Citation Details In-Document Search Title: Simulation, Modeling, and Crystal...

  15. Thermoelectric properties of AgSbTe? from first-principles calculations

    SciTech Connect (OSTI)

    Rezaei, Nafiseh; Akbarzadeh, Hadi; Hashemifar, S. Javad

    2014-09-14

    The structural, electronic, and transport properties of AgSbTe? are studied by using full-relativistic first-principles electronic structure calculation and semiclassical description of transport parameters. The results indicate that, within various exchange-correlation functionals, the cubic Fd3?m and trigonal R3?m structures of AgSbTe? are more stable than two other considered structures. The computed Seebeck coefficients at different values of the band gap and carrier concentration are accurately compared with the available experimental data to speculate a band gap of about 0.1–0.35 eV for AgSbTe? compound, in agreement with our calculated electronic structure within the hybrid HSE (Heyd-Scuseria-Ernzerhof) functional. By calculating the semiclassical Seebeck coefficient, electrical conductivity, and electronic part of thermal conductivity, we present the theoretical upper limit of the thermoelectric figure of merit of AgSbTe? as a function of temperature and carrier concentration.

  16. CsBi4Te6: A High-Performance Thermoelectric Material for Low...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    CsBi4Te6: A High-Performance Thermoelectric Material for Low-Temperature Applications Home Author: D.Y. Chung, T. Hogan, P. Brazis, M. Rocci-Lane, C. Kannawurf, M. Bastea, C. Uher,...

  17. Deformation and shape transitions in hot rotating neutron deficient Te isotopes

    SciTech Connect (OSTI)

    Aggarwal, Mamta; Mazumdar, I.

    2009-08-15

    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.

  18. Spin glass in semiconducting KFe1.05Ag0.88Te2 single crystals

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ryu, H.; Lei, H.; Klobes, B.; Warren, J. B.; Hermann, R. P.; Petrovic, C.

    2015-05-26

    We report discovery of KFe1.05Ag0.88Te2 single crystals with semiconducting spin glass ground state. Composition and structure analysis suggest nearly stoichiometric I4/mmm space group but allow for the existence of vacancies, absent in long range semiconducting antiferromagnet KFe1.05Ag0.88Te2. The subtle change in stoichometry in Fe/Ag sublattice changes magnetic ground state but not conductivity, giving further insight into the semiconducting gap mechanism.

  19. Milagro: A TeV Gamma-Ray Monitor of the Northern Hemisphere Sky

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    transients, such as gamma-ray bursts, and all sky surveys are diÆcult. A new type of TeV -ray observatoryMilagro: A TeV Gamma-Ray Monitor of the Northern Hemisphere Sky B.L. Dingus 1 , R. Atkins 1 , W type of very high energy (> a few 100 GeV) gamma-ray observatory, Milagro, has been built with a large

  20. Method of synthesizing and growing copper-indium-diselenide (CuInSe/sub 2/) crystals

    DOE Patents [OSTI]

    Ciszek, T.F.

    1984-11-29

    A process for preparing CuInSe/sub 2/ crystals includes melting a sufficient quantity of B/sub 2/O/sub 2/ along with stochiometric quantities of Cu, In, and Se in a crucible in a high-pressure atmosphere of inert gas to encapsulate the CuInSe/sub 2/ melt and confine the Se to the crucible. Additional Se in the range of 1.8 to 2.2% over the stochiometric quantity is preferred to make up for small amounts of Se lost in the process. The melt can then be cooled slowly to form the crystal as direct solidification, or the crystal can be grown by inserting a seed crystal through the B/sub 2/O/sub 3/ encapsulate into contact with the CuInSe/sub 2/ melt and withdrawing the seed upwardly to grow the crystal thereon from the melt.

  1. Observation and Measurement of Se-79 in SRS High-Level Tank Fission Product Waste

    SciTech Connect (OSTI)

    Dewberry, R.A.

    2000-08-21

    The authors report the first observation of confirmed Se-79 activity in Savannah River Site high level fission product waste. Se-79 was measured after a seven step chemical treatment to remove interfering activity from Cs-137, Sr-90, and plutonium at levels 105 times higher than the observed Se-79 content and to remove Tc-99 at levels 300 times higher than observed Se-79. Se-79 was measured by liquid scintillation beta-decay counting after specific tests to eliminate uncertainties from possible contributions from Tc-99, Pm-147, Sm-151, Zr-93, or Pu-241, whose beta-decay spectra could appear similar to that of Se-79, and whose content would be expected at levels near or greater than Se-79.

  2. Oxygen Incorporation During Fabrication of Substrate CdTe Photovoltaic Devices: Preprint

    SciTech Connect (OSTI)

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

    2012-06-01

    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%.

  3. Abundance determinations in HII regions: model fitting versus Te-method

    E-Print Network [OSTI]

    L. S. Pilyugin

    2002-11-14

    The discrepancy between the oxygen abundances in high-metallicity HII regions determined through the Te-method (and/or through the corresponding "strong lines - oxygen abundance" calibration) and that determined through the model fitting (and/or through the corresponding "strong lines - oxygen abundance" calibration) is discussed. It is suggested to use the interstellar oxygen abundance in the solar vicinity, derived with very high precision from the high-resolution observations of the weak interstellar absorption lines towards the stars, as a "Rosetta stone" to verify the validity of the oxygen abundances derived in HII regions with the Te-method at high abundances. The agreement between the value of the oxygen abundance at the solar galactocentric distance traced by the abundances derived in HII regions through the Te-method and that derived from the interstellar absorption lines towards the stars is strong evidence in favor of that i) the two-zone model for Te seems to be a realistic interpretation of the temperature structure within HII regions, and ii) the classic Te-method provides accurate oxygen abundances in HII regions. It has been concluded that the "strong lines - oxygen abundance" calibrations must be based on the HII regions with the oxygen abundances derived with the Te-method but not on the existing grids of the models for HII regions.

  4. Enhanced thermoelectric performance in Cd doped CuInTe{sub 2} compounds

    SciTech Connect (OSTI)

    Cheng, N.; Liu, R.; Bai, S.; Shi, X. Chen, L.

    2014-04-28

    CuIn{sub 1?x}Cd{sub x}Te{sub 2} materials (x?=?0, 0.02, 0.05, and 0.1) are prepared using melting-annealing method and the highly densified bulk samples are obtained through Spark Plasma Sintering. The X-ray diffraction data confirm that nearly pure chalcopyrite structures are obtained in all the samples. Due to the substitution of Cd at In sites, the carrier concentration is greatly increased, leading to much enhanced electrical conductivity and power factor. The single parabolic band model is used to describe the electrical transport properties of CuInTe{sub 2} and the low temperature Hall mobility is also modeled. By combing theoretical model and experiment data, the optimum carrier concentration in CuInTe{sub 2} is proposed to explain the greatly enhanced power factors in the Cd doped CuInTe{sub 2}. In addition, the thermal conductivity is reduced by extra phonon scattering due to the atomic mass and radius fluctuations between Cd and In atoms. The maximum zTs are observed in CuIn{sub 0.98}Cd{sub 0.02}Te{sub 2} and CuIn{sub 0.9}Cd{sub 0.1}Te{sub 2} samples, which are improved by over 100% at room temperature and around 20% at 600?K.

  5. Ion-beam treatment to prepare surfaces of p-CdTe films

    DOE Patents [OSTI]

    Gessert, Timothy A. (Conifer, CO)

    2001-01-01

    A method of making a low-resistance electrical contact between a p-CdTe layer and outer contact layers by ion beam processing comprising: a) placing a CdS/CdTe device into a chamber and evacuating the chamber; b) orienting the p-CdTe side of the CdS/CdTe layer so that it faces apparatus capable of generating Ar atoms and ions of preferred energy and directionality; c) introducing Ar and igniting the area of apparatus capable of generating Ar atoms and ions of preferred energy and directionality in a manner so that during ion exposure, the source-to-substrate distance is maintained such that it is less than the mean-free path or diffusion length of the Ar atoms and ions at the vacuum pressure; d) allowing exposure of the p-CdTe side of the device to said ion beam for a period less than about 5 minutes; and e) imparting movement to the substrate to control the real uniformity of the ion-beam exposure on the p-CdTe side of the device.

  6. DEGREE-SCALE GeV 'JETS' FROM ACTIVE AND DEAD TeV BLAZARS

    SciTech Connect (OSTI)

    Neronov, A.; Semikoz, D.; Kachelriess, M.; Ostapchenko, S.; Elyiv, A.

    2010-08-20

    We show that images of TeV blazars in the GeV energy band should contain, along with point-like sources, degree-scale jet-like extensions. These GeV extensions are the result of electromagnetic cascades initiated by TeV {gamma}-rays interacting with extragalactic background light and the deflection of the cascade electrons/positrons in extragalactic magnetic fields (EGMFs). Using Monte Carlo simulations, we study the spectral and timing properties of the degree-scale extensions in simulated GeV band images of TeV blazars. We show that the brightness profile of such degree-scale extensions can be used to infer the light curve of the primary TeV {gamma}-ray source over the past 10{sup 7} yr, i.e., over a time scale comparable to the lifetime of the parent active galactic nucleus. This implies that the degree-scale jet-like GeV emission could be detected not only near known active TeV blazars, but also from 'TeV blazar remnants', whose central engines were switched off up to 10 million years ago. Since the brightness profile of the GeV 'jets' depends on the strength and the structure of the EGMF, their observation provides additional information about the EGMF.

  7. Structural characterization of Bi{sub 2}Te{sub 3} and Sb{sub 2}Te{sub 3} as a function of temperature using neutron powder diffraction and extended X-ray absorption fine structure techniques

    SciTech Connect (OSTI)

    Mansour, A. N.; Wong-Ng, W.; Huang, Q.; Tang, W.; Thompson, A.; Sharp, J.

    2014-08-28

    The structure of Bi{sub 2}Te{sub 3} (Seebeck coefficient Standard Reference Material (SRM™ 3451)) and the related phase Sb{sub 2}Te{sub 3} have been characterized as a function of temperature using the neutron powder diffraction (NPD) and the extended X-ray absorption fine structure (EXAFS) techniques. The neutron structural studies were carried out from 20?K to 300?K for Bi{sub 2}Te{sub 3} and from 10?K to 298?K for Sb{sub 2}Te{sub 3}. The EXAFS technique for studying the local structure of the two compounds was conducted from 19?K to 298?K. Bi{sub 2}Te{sub 3} and Sb{sub 2}Te{sub 3} are isostructural, with a space group of R3{sup ¯}m. The structure consists of repeated quintuple layers of atoms, Te2-M-Te1-M-Te2 (where M?=?Bi or Sb) stacking along the c-axis of the unit cell. EXAFS was used to examine the bond distances and static and thermal disorders for the first three shells of Bi{sub 2}Te{sub 3} and Sb{sub 2}Te{sub 3} as a function of temperature. The temperature dependencies of thermal disorders were analyzed using the Debye and Einstein models for lattice vibrations. The Debye and Einstein temperatures for the first two shells of Bi{sub 2}Te{sub 3} are similar to those of Sb{sub 2}Te{sub 3} within the uncertainty in the data. However, the Debye and Einstein temperatures for the third shell of Bi-Bi are significantly lower than those of the third shell of Sb-Sb. The Einstein temperature for the third shell is consistent with a soft phonon mode in both Bi{sub 2}Te{sub 3} and Sb{sub 2}Te{sub 3}. The lower Einstein temperature of Bi-Bi relative to Sb-Sb is consistent with the lower value of thermal conductivity of Bi{sub 2}Te{sub 3} relative to Sb{sub 2}Te{sub 3}.

  8. SLU, Box 58, SE-230 53Alnarp, Sverige tel: +46 (0)40-4150 00 Org.nr 202100-2817 info@slu.se

    E-Print Network [OSTI]

    .slu.se 1(7) FUSE- Future Urban Sustainable Environments Caroline Dahl, projektledare STRATEGISK PLAN Strategisk plan för FUSE verksamhetsperiod 2013-2016 Projektnamn: Future Urban Sustainable Environment, FUSE

  9. Electronic and thermoelectric properties of Ce{sub 3}Te{sub 4} and La{sub 3}Te{sub 4} computed with density functional theory with on-site Coulomb interaction correction

    SciTech Connect (OSTI)

    Vo, Trinh; Allmen, Paul von; Huang, Chen-Kuo; Ma, James; Bux, Sabah; Fleurial, Jean-Pierre [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)

    2014-10-07

    The electronic properties and Seebeck coefficients of Ce{sub 3}Te{sub 4} and La{sub 3}Te{sub 4} are computed using Density Functional Theory with on-site Coulomb interaction correction. We found that the Seebeck coefficients of Ce{sub 3}Te{sub 4} and La{sub 3}Te{sub 4} are almost equal at temperatures larger than the Curie temperature of Ce{sub 3}Te{sub 4}, and in good agreement with the measurements reported by May et al. [Phys. Rev. B 86, 035135 (2012)]. At temperatures below the Curie temperature, the Seebeck coefficient of Ce{sub 3}Te{sub 4} increases due to the ferromagnetic ordering, which leads the f-electron of Ce to contribute to the Seebeck coefficient in the relevant range of electron concentration.

  10. ADVANCES IN SE-79 ANALYSES ON SAVANNAH RIVER SITE RADIOACTIVE WASTE MATRICES

    SciTech Connect (OSTI)

    Diprete, D; C Diprete, C; Ned Bibler, N; Cj Bannochie, C; Michael Hay, M

    2009-03-16

    Waste cleanup efforts underway at the United States Department of Energy's (DOE) Savannah River Site (SRS) in South Carolina, as well as other DOE nuclear sites, have created a need to characterize {sup 79}Se in radioactive waste inventories. Successful analysis of {sup 79}Se in high activity waste matrices is challenging for a variety of reasons. As a result of these unique challenges, the successful quantification of {sup 79}Se in the types of matrices present at SRS requires an extremely efficient and selective separation of {sup 79}Se from high levels of interfering radionuclides. A robust {sup 79}Se radiochemical separation method has been developed at the Savannah River National Laboratory (SRNL) which is routinely capable of successfully purifying {sup 79}Se from a wide range of interfering radioactive species. In addition to a dramatic improvements in the Kd, ease, and reproducibility of the analysis, the laboratory time has been reduced from several days to only 6 hours.

  11. Structural phase transitions on the nanoscale: The crucial pattern in the phase-change materials Ge2Sb2Te5 and GeTe

    E-Print Network [OSTI]

    Structural phase transitions on the nanoscale: The crucial pattern in the phase-change materials Ge and computer memory, but the structure of the amorphous phases and the nature of the phase transition of types A Ge and Sb and B Te , an "ABAB square." The rapid amorphous-to-crystalline phase change

  12. Nuclear structure of 140Te with N = 88: Structural symmetry and asymmetry in Te isotopes with respect to the double-shell closure Z = 50 and N = 82

    E-Print Network [OSTI]

    Moon, C -B; Lee, C S; Odahara, A; Lozeva, R; Yagi, A; Browne, F; Nishimura, S; Doornenbal, P; Lorusso, G; Söderström, P -A; Sumikama, T; Watanabe, H; Isobe, T; Baba, H; Sakurai, H; Daido, R; Fang, Y; Nishibata, H; Patel, Z; Rice, S; Sinclair, L; Wu, J; Xu, Z Y; Yokoyama, R; Kubo, T; Inabe, N; Suzuki, H; Fukuda, N; Kameda, D; Takeda, H; Ahn, D S; Murai, D; Garrote, F L Bello; Daugas, J M; Didierjean, F; Ideguchi, E; Ishigaki, T; Jung, H S; Komatsubara, T; Kwon, Y K; Morimoto, S; Niikura, M; Nishizuka, I; Tshoo, K

    2015-01-01

    We study for the first time the internal structure of 140Te through the beta-delayed gamma-ray spectroscopy of 140Sb. The very neutron-rich 140Sb, Z = 51 and N = 89, ions were produced by the in-flight fission of 238U beam on a 9Be target at 345 MeV per nucleon at the Radioactive Ion Beam Factory, RIKEN. The half-life and spin-parity of 140Sb are reported as 124(30) ms and (4-), respectively. In addition to the excited states of 140Te produced by the beta-decay branch, the beta-delayed one-neutron and two-neutron emission branches were also established. By identifying the first 2+ and 4+ excited states of 140Te, we found that Te isotopes persist their vibrator character with E(4+)/E(2+) = 2. We discuss the distinctive features manifest in this region, such as valence neutron symmetry and asymmetry, revealed in pairs of isotopes with the same neutron holes and particles with respect to N = 82.

  13. Enhanced ripening behavior of Mg-doped CdSe quantum dots

    E-Print Network [OSTI]

    Kim, Tae-Geun

    In this study, CdO and Mg acetate were added into a mixture of paraffin oil and oleic acid (45:5) by 5 and 1 mEnhanced ripening behavior of Mg-doped CdSe quantum dots Yun-Mo Sung,a) Woo-Chul Kwak, and Woong November 2007; accepted 24 March 2008) Pure CdSe and Mg-doped CdSe nanocrystal quantum dots were

  14. Hot-pressed ceramic Cr2+ :ZnSe gain-switched

    E-Print Network [OSTI]

    Mirov, Sergey B.

    Hot-pressed ceramic Cr2+ :ZnSe gain-switched laser A. Gallian, V. V. Fedorov, and S. B. Mirov: The technology of hot-pressed Cr2+ :ZnSe ceramic preparation is reported. Comparative gain-switched lasing of hot­pressed ceramic and CVD grown Cr2+ :ZnSe samples with slope efficiencies up to 10 % and output energies up to 2 m

  15. DISSERTATION DEVICE PHYSICS OF Cu(In,Ga)Se2 THIN-FILM SOLAR CELLS

    E-Print Network [OSTI]

    Sites, James R.

    OF Cu(In,Ga)Se2 THIN-FILM SOLAR CELLS Thin-film solar cells have the potential to be an important contributor to the global energy demand by the mid-21st-century. Cu(In,Ga)Se2 (CIGS) solar cells, which haveDISSERTATION DEVICE PHYSICS OF Cu(In,Ga)Se2 THIN-FILM SOLAR CELLS Submitted by Markus Gloeckler

  16. First-epoch VLBA imaging of 20 new TeV blazars

    SciTech Connect (OSTI)

    Piner, B. Glenn; Edwards, Philip G.

    2014-12-10

    We present Very Long Baseline Array (VLBA) images of 20 TeV blazars not previously well studied on the parsec scale. All 20 of these sources are high-frequency peaked BL Lac objects (HBLs). Observations were made between August and December of 2013 at a frequency of 8.4 GHz. These observations represent the first epoch of a VLBA monitoring campaign on these blazars, and they significantly increase the fraction of TeV HBLs studied with high-resolution imaging. The peak very long baseline interferometry (VLBI) flux densities of these sources range from ?10 to ?100 mJy bm{sup –1}, and parsec-scale jet structure is detected in all sources. About half of the VLBI cores are resolved, with brightness temperature upper limits of a few times 10{sup 10} K, and we find that a brightness temperature of ?2 × 10{sup 10} K is consistent with the VLBI data for all but one of the sources. Such brightness temperatures do not require any relativistic beaming to reduce the observed value below commonly invoked intrinsic limits; however, the lack of detection of counterjets does place a modest limit on the bulk Lorentz factor of ? ? 2. These data are thus consistent with a picture where weak-jet sources like the TeV HBLs develop significant velocity structures on parsec scales. We also extend consideration to the full sample of TeV HBLs by combining the new VLBI data with VLBI and gamma-ray data from the literature. By comparing measured VLBI and TeV fluxes to samples with intrinsically uncorrelated luminosities generated by Monte Carlo simulations, we find a marginally significant correlation between the VLBI and TeV fluxes for the full TeV HBL sample.

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

    SciTech Connect (OSTI)

    2012-12-31

    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.

  18. Mechanical and electronic-structure properties of compressed CdSe tetrapod nanocrystals

    E-Print Network [OSTI]

    Schrier, Joshua; Lee, Byounghak; Wang, Lin-Wang

    2008-01-01

    Mechanical and electronic-structure properties of compressed94720 USA The coupling of mechanical and optical propertiestheoretical examination of the mechanical properties of CdSe

  19. Photovoltaic performance of ultra-small PbSe quantum dots

    E-Print Network [OSTI]

    Ma, Wanli

    2014-01-01

    Y; Alivisatos, AP, Photovoltaic Devices Employing TernaryPhotovoltaic performance of ultra-small PbSe quantum dotsquantum dot, solar cell, photovoltaic, quantum size effect

  20. Photovoltaic Devices Employing Ternary PbSxSe1-x Nanocrystals

    E-Print Network [OSTI]

    Alivisatos, A. Paul

    2009-01-01

    Photovoltaic Devices Employing Ternary PbS x Se 1-xalloy nanoparticles. Photovoltaic devices made using ternaryInformation for Efficient Photovoltaic Devices Employing

  1. Optical properties of ZnO/ZnS and ZnO/ZnTe heterostructures for photovoltaic applications

    E-Print Network [OSTI]

    Schrier, Joshua; Demchenko, Denis O.; Wang, Lin-Wang; Alivisatos, A. Paul

    2008-01-01

    ZnTe heterostructures for photovoltaic applications Joshuatoo large for optimal photovoltaic e?ciency. By using band-nanowires can be used as photovoltaic devices with organic

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

    E-Print Network [OSTI]

    Ballestrero, Alessandro; Maina, Ezio

    2012-01-01

    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.

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

    E-Print Network [OSTI]

    Alessandro Ballestrero; Diogo Buarque Franzosi; Ezio Maina

    2012-03-13

    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.

  4. Static atomic displacements in a CdTe epitaxial layer on a GaAs substrate

    SciTech Connect (OSTI)

    Horning, R.D.; Staudenmann, J.

    1987-05-25

    A (001)CdTe epitaxial layer on a (001)GaAs substrate was studied by x-ray diffraction between 10 and 360 K. The CdTe growth took place at 380 /sup 0/C in a vertical gas flow metalorganic chemical vapor deposition reactor. Lattice parameters and integrated intensities of both the substrate and the epitaxial layer using the (00l) and (hhh) Bragg reflections reveal three important features. Firstly, the GaAs substrate does not exhibit severe strain after deposition and it is as perfect as a bulk GaAs. Secondly, the CdTe unit cell distorts tetragonally with a/sub perpendicular/>a/sub parallel/ below 300 K. The decay of the (00l) reflection intensities as a function of the temperature yields a Debye temperature of 142 K, the same value as for bulk CdTe. Thirdly, a temperature-dependent isotropic static displacement of the Cd and the Te atoms is introduced to account for the anomalous behavior of the (hhh) intensities.

  5. Phenomenology of TeV Right-handed Neutrino and the Dark Matter Model

    E-Print Network [OSTI]

    Kingman Cheung; Osamu Seto

    2004-03-08

    In a model of TeV right-handed (RH) neutrino by Krauss, Nasri, and Trodden, the sub-eV scale neutrino masses are generated via a 3-loop diagram with the vanishing see-saw mass forbidden by a discrete symmetry, and the TeV mass RH neutrino is simultaneously a novel candidate for the cold dark matter. However, we show that with a single RH neutrino it is not possible to generate two mass-square differences as required by the oscillation data. We extend the model by introducing one more TeV RH neutrino and show that it is possible to satisfy the oscillation pattern within the modified model. After studying in detail the constraints coming from the dark matter, lepton flavor violation and the muon anomalous magnetic moment, and the neutrinoless double beta decay, we explore the parameter space and derive predictions of the model. Finally, we study the production and decay signatures of the TeV RH neutrinos at TeV $e^+ e^-/\\mu^+ \\mu^-$ colliders.

  6. Reduction of Fermi level pinning and recombination at polycrystalline CdTe surfaces by laser irradiation

    SciTech Connect (OSTI)

    Simonds, Brian J.; Kheraj, Vipul; Palekis, Vasilios; Ferekides, Christos; Scarpulla, Michael A.

    2015-06-14

    Laser processing of polycrystalline CdTe is a promising approach that could potentially increase module manufacturing throughput while reducing capital expenditure costs. For these benefits to be realized, the basic effects of laser irradiation on CdTe must be ascertained. In this study, we utilize surface photovoltage spectroscopy (SPS) to investigate the changes to the electronic properties of the surface of polycrystalline CdTe solar cell stacks induced by continuous-wave laser annealing. The experimental data explained within a model consisting of two space charge regions, one at the CdTe/air interface and one at the CdTe/CdS junction, are used to interpret our SPS results. The frequency dependence and phase spectra of the SPS signal are also discussed. To support the SPS findings, low-temperature spectrally-resolved photoluminescence and time-resolved photoluminescence were also measured. The data show that a modest laser treatment of 250?W/cm{sup 2} with a dwell time of 20?s is sufficient to reduce the effects of Fermi level pinning at the surface due to surface defects.

  7. An Experiment to Locate the Site of TeV Flaring in M87

    SciTech Connect (OSTI)

    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.

    2012-05-18

    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.

  8. Discovery of TeV Gamma-Ray Emission from the Cygnus Region of the Galaxy

    E-Print Network [OSTI]

    A. A. Abdo; B. Allen; D. Berley; E. Blaufuss; S. Casanova; C. Chen; D. G. Coyne; R. S. Delay; B. L. Dingus; R. W. Ellsworth; L. Fleysher; R. Fleysher; M. M. Gonzalez; J. A. Goodman; E. Hays; C. M. Hoffman; B. E. Kolterman; L. A. Kelley; C. P. Lansdell; J. T. Linnemann; J. E. McEnery; A. I. Mincer; I. V. Moskalenko; P. Nemethy; D. Noyes; J. M. Ryan; F. W. Samuelson; P. M. Saz Parkinson; M. Schneider; A. Shoup; G. Sinnis; A. J. Smith; A. W. Strong; G. W. Sullivan; V. Vasileiou; G. P. Walker; D. A. Williams; X. W. Xu; G. B. Yodh

    2006-11-21

    The diffuse gamma radiation arising from the interaction of cosmic ray particles with matter and radiation in the Galaxy is one of the few probes available to study the origin of the cosmic rays. Milagro is a water Cherenkov detector that continuously views the entire overhead sky. The large field-of-view combined with the long observation time makes Milagro the most sensitive instrument available for the study of large, low surface brightness sources such as the diffuse gamma radiation arising from interactions of cosmic radiation with interstellar matter. In this paper we present spatial and flux measurements of TeV gamma-ray emission from the Cygnus Region. The TeV image shows at least one new source MGRO J2019+37 as well as correlations with the matter density in the region as would be expected from cosmic-ray proton interactions. However, the TeV gamma-ray flux as measured at ~12 TeV from the Cygnus region (after excluding MGRO J2019+37) exceeds that predicted from a conventional model of cosmic ray production and propagation. This observation indicates the existence of either hard-spectrum cosmic-ray sources and/or other sources of TeV gamma rays in the region.

  9. Closing up on Dark Sectors at Colliders: from 14 to 100 TeV

    E-Print Network [OSTI]

    Harris, Philip; Spannowsky, Michael; Williams, Ciaran

    2015-01-01

    We investigate the reach of the LHC Run 2 and that of a future circular hadron collider with up to 100 TeV centre of mass energy for the exploration of potential Dark Matter sectors. These dark sectors are conveniently and broadly described by simplified models. The simplified models we consider provide microscopic descriptions of interactions between the Standard Model partons and the dark sector particles mediated by the four basic types of messenger fields: scalar, pseudo-scalar, vector or axial-vector. Our analysis extends and updates the previously available results for the LHC at 8 and 14 TeV to 100 TeV for models with all four messenger types. We revisit and improve the analysis at 14 TeV, by studying a variety of analysis techniques, concluding that the most discriminating variables correspond to the missing transverse energy and the azimuthal angle between jets in the final state. Going to 100 TeV, the limits on simplified models of Dark Matter are enhanced significantly, in particular for heavier me...

  10. PERFORMANCE OF CdSe TETRAPODS-GOLD AS NANOSTRUCTURE ELECTROCHEMICAL MATERIALS IN PHOTOVOLTAIC CELLS

    E-Print Network [OSTI]

    Natelson, Douglas

    PERFORMANCE OF CdSe TETRAPODS-GOLD AS NANOSTRUCTURE ELECTROCHEMICAL MATERIALS IN PHOTOVOLTAIC CELLS antenna arrays are assembled by coating on CdSe tetrapod templates; the rectifying barrier is formed and reduce the costs associated with conventional solar cells, including multi-bandgap materials [5

  11. Ultrafast Spectroscopy of CdSe Nanocrystals: Morphological and Environmental Effects on Nonradiative and Nonadiabatic Relaxation

    E-Print Network [OSTI]

    Xu, Xianfan

    Ultrafast Spectroscopy of CdSe Nanocrystals: Morphological and Environmental Effects of various morpholo- gies has been demonstrated in CdSe, such as quantum dots (QDs),3 quantum rods (QRs),4 devices and technologies have come to fruition, for example, nanocrystal solar cells (NCSC),7 lasers,8

  12. Volume 42, number 2 OPTICSCOMMUNICATIONS 15 June 1982 ELECTRON BEAM PUMPED CW Se II LASER ~

    E-Print Network [OSTI]

    Rocca, Jorge J.

    Volume 42, number 2 OPTICSCOMMUNICATIONS 15 June 1982 ELECTRON BEAM PUMPED CW Se II LASER ~ J of singlyionized seleniumusingan electron beam to excite a He-Se mixture. The variation of the laser output power as a function of the electron beam dischargeparameters is reported. Recently we obtained cw laser radiation from

  13. Superconductivity in Strong Spin Orbital Coupling Compound Sb2Se3

    E-Print Network [OSTI]

    Shen, Guoyin

    Superconductivity in Strong Spin Orbital Coupling Compound Sb2Se3 P. P. Kong1 , F. Sun1,3 , L. Y induce Sb2Se3 into a topological nontrivial state. Here, we report on the discovery of superconductivity superconductive at high pressures above 10 GPa proceeded by a pressure induced insulator to metal like transition

  14. Photovoltaic cells fabricated by electrophoretic deposition of CdSe nanocrystals

    E-Print Network [OSTI]

    Smith, Nathanael J.

    Photovoltaic cells fabricated by electrophoretic deposition of CdSe nanocrystals Nathanael J. Smith Electrophoretic deposition was used to deposit CdSe nanocrystals on TiO2 for use in photovoltaic cells formed. A solar cell constructed using electrophoretic deposition exhibited a photovoltaic response from

  15. ME/SE 762 Nonlinear Systems and Control Location: SOC B63

    E-Print Network [OSTI]

    Lin, Xi

    ME/SE 762 Nonlinear Systems and Control Location: SOC B63 Time: Tue & Thu 12-2 Instructor: Calin-4 #12;ME/SE 762 Nonlinear Systems and Control Prerequisites: a grad-level class on linear systems: · stability analysis of nonlinear systems (with emphasis on Lyapunov theory) · nonlinear feedback control

  16. Development of a Low Cost Insulated Foil Substrate for Cu(InGaSe)2 Photovoltaics

    SciTech Connect (OSTI)

    ERTEN ESER

    2012-01-22

    The project validated the use of stainless steel flexible substrate coated with silicone-based resin dielectric, developed by Dow Corning Corporation, for Cu(InGa)Se2 based photovoltaics. The projects driving force was the high performance of Cu(InGa)Se2 based photovoltaics coupled with potential cost reduction that could be achieved with dielectric coated SS web substrate.

  17. 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 (OSTI)

    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)

    2011-03-15

    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.

  18. Surface Plasmon Excitation via Au Nanoparticles in CdSe Semiconductor

    SciTech Connect (OSTI)

    Pradhan, A. K.; Konda, R. B.; Mundle, R.; Mustafa, H.; Bamiduro, O.; Roy, U. N.; Cui, Y.; Burger, A.

    2008-10-23

    We present experimental evidence for the large Raman and photoluminescence enhancement in CdSe semiconductor films grown on Si and glass substrates due to excitation of surface plasmon resonances in proximate gold metal nanoparticles deposited on the surface of CdSe film. Heterojunction diodes containing n-CdSe on p-Si semiconductor were fabricated and the surface of the diodes was in situ coated with Au nanoparticles using the ultra-high vacuum pulsed-laser deposition technique. A significant enhancement of the photocurrent was obtained in CdSe/p-Si containing Au nanoparticles on the surface compared to CdSe/p-Si due to the enhanced photo-absorption within the semiconductor by the phenomenon of surface plasmon resonance. These observations suggest a variety of approaches for improving the performance of devices such as photodetectors, photovoltaic, and related devices, including biosensors.

  19. Approved Module Information for SE12EM, 2014/5 Module Title/Name: Mathematics for 1st year Engineers Module Code: SE12EM

    E-Print Network [OSTI]

    Neirotti, Juan Pablo

    Engineers Module Code: SE12EM School: Engineering and Applied Science Module Type: Standard Module New (Enhanced Honours) Programmes in which available: BEng Mechanical Engineering Systems. BEng/MEng Electromechanical Engineering. BEng/MEng Mechanical Engineering. BEng Electrical Engineering Systems. BEng

  20. Module Information for SE0SLF, 2015/6 -APPROVED Module Title/Name: Systems and Logistics Foundations Module Code: SE0SLF

    E-Print Network [OSTI]

    Rebollo-Neira, Laura

    Module Information for SE0SLF, 2015/6 - APPROVED Module Title/Name: Systems and Logistics thinking and its role in engineering ? To provide students with a knowledge of the role of logistics in society Module Learning Outcomes: ? To describe the role of systems and logistics in engineering and wider

  1. Measurement of inclusive and differential fiducial cross sections for Higgs boson production in the H-to-4l decay channel in p-p collisions at 7~TeV and 8~TeV

    E-Print Network [OSTI]

    CMS Collaboration

    2015-01-01

    Measurements of the inclusive and differential fiducial cross sections for Higgs boson production in p-p collisions at center-of-mass energies of $\\sqrt{s}=7$~TeV and $\\sqrt{s}=8$~TeV using H$\\rightarrow 4\\ell$ decays ($\\ell = e, \\mu$) are presented.

  2. High Efficiency CdTe/CdS Thin Film Solar Cells Prepared by Treating CdTe Films with a Freon Gas in Substitution of CdCl2

    E-Print Network [OSTI]

    Romeo, Alessandro

    High Efficiency CdTe/CdS Thin Film Solar Cells Prepared by Treating CdTe Films with a Freon Gas a sufficient conversion efficiency to be considered for an industrial application. The fabrication process observed. Solar cell efficiency obtained with this treatment, close to 16%, is comparable if not larger

  3. First-Principles Study of Surface States of Bi{sub 2}Te{sub 3}

    SciTech Connect (OSTI)

    Park, Kyungwha [Department of Physics, Virginia Tech, Blacksburg, Virginia 24061 (United States)

    2011-12-26

    Bi{sub 2}Te{sub 3} is a topological insulator with time reversal symmetry possessing a single Dirac cone at a given surface. The surface states of topological insulators play a critical role in exotic physical phenomena and their applications. We investigate the surface states of thin films of Bi{sub 2}Te{sub 3}(111) using density-functional theory including spin-orbit coupling. Considering one to six quintuple layers (QLs) of Bi{sub 2}Te{sub 3} films, we identify the surface states from calculated band structures using the decay length of the surface states and electron density plots. We show that the films of 1 and 2 QLs are too thin to hold the surface states protected topologically, and that for thicker films bands identified as surface states at {Gamma}-bar lose their surface-state features away from {Gamma}-bar. This method can be applied to other topological insulators.

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

    SciTech Connect (OSTI)

    Siemons, W.

    2010-02-24

    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.

  5. Superconducting thin films of (100) and (111) oriented indium doped topological crystalline insulator SnTe

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Si, W.; Zhang, C.; Wu, L.; Ozaki, T.; Gu, G.; Li, Q.

    2015-09-01

    Recent discovery of the topological crystalline insulator SnTe has triggered a search for topological superconductors, which have potential application to topological quantum computing. The present work reports on the superconducting properties of indium doped SnTe thin films. The (100) and (111) oriented thin films were epitaxially grown by pulsed-laser deposition on (100) and (111) BaF2 crystalline substrates respectively. The onset superconducting transition temperatures are about 3.8 K for (100) and 3.6 K for (111) orientations, slightly lower than that of the bulk. Magneto-resistive measurements indicate that these thin films may have upper critical fields higher than that of the bulk.more »With large surface-to-bulk ratio, superconducting indium doped SnTe thin films provide a rich platform for the study of topological superconductivity and potential device applications based on topological superconductors.« less

  6. Measurements of proton induced reaction cross sections on 120Te for the astrophysical p-process

    E-Print Network [OSTI]

    R. T. Güray; N. Özkan; C. Yalç?n; A. Palumbo; R. deBoer; J. Görres; P. J. Leblanc; S. O'Brien; E. Strandberg; W. P. Tan; M. Wiescher; Zs. Fülöp; E. Somorjai; H. Y. Lee; J. P. Greene

    2009-08-28

    The total cross sections for the 120Te(p,gamma)121I and 120Te(p,n)120I reactions have been measured by the activation method in the effective center-of-mass energies between 2.47 MeV and 7.93 MeV. The targets were prepared by evaporation of 99.4 % isotopically enriched 120Te on Aluminum and Carbon backing foils, and bombarded with proton beams provided by the FN tandem accelerator at the University of Notre Dame. The cross sections and $S$ factors were deduced from the observed gamma ray activity, which was detected off-line by two Clover HPGe detectors mounted in close geometry. The results are presented and compared with the predictions of statistical model calculations using the codes NON-SMOKER and TALYS.

  7. Pair correlations in neutrinoless double {beta} decay candidate {sup 130}Te.

    SciTech Connect (OSTI)

    Bloxham, T.; Kay, B. P.; Schiffer, J. P.; Clark, J. A.; Deibel, C. M.; Freeman, S. J.; Freedman, S. J.; Howard, A. M.; McAllister, S. A.; Parker, P. D.; Sharp, D. K.; Thomas, J. S. (Physics); ( PSC-USR); (LBNL); (Michigan State Univ.); (Univ. of Manchester); (Yale Univ.)

    2010-08-16

    Pair correlations in the ground state of {sup 130}Te have been investigated using pair-transfer experiments to explore the validity of approximations in calculating the matrix element for neutrinoless double-{beta} decay. This nucleus is a candidate for the observation of such decay, and a good understanding of its structure is crucial for eventual calculations of the neutrino mass, should such a decay indeed be observed. For proton-pair adding, strong transitions to excited 0{sup +} states had been observed in the Te isotopes by Alford et al. [Nucl. Phys. A 323, 339 (1979)], indicating a breaking of the BCS approximation for protons in the ground state. We measured the neutron-pair removing (p,t) reaction on {sup 130}Te and found no indication of a corresponding splitting of the BCS nature of the ground state for neutrons.

  8. Pair correlations in the neutrinoless double-{beta} decay candidate {sup 130}Te

    SciTech Connect (OSTI)

    Bloxham, T.; Freedman, S. J. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Kay, B. P.; Schiffer, J. P.; Clark, J. A. [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 for Nuclear Astrophysics, Michigan State University, East Lansing, Michigan 48825 (United States); Freeman, S. J.; Howard, A. M.; McAllister, S. A.; Sharp, D. K.; Thomas, J. S. [Schuster Laboratory, University of Manchester, Manchester, M13 9PL (United Kingdom); Parker, P. D. [A. W. Wright Nuclear Structure Laboratory, Yale University, New Haven, Connecticut 06520 (United States)

    2010-08-15

    Pair correlations in the ground state of {sup 130}Te have been investigated using pair-transfer experiments to explore the validity of approximations in calculating the matrix element for neutrinoless double-{beta} decay. This nucleus is a candidate for the observation of such decay, and a good understanding of its structure is crucial for eventual calculations of the neutrino mass, should such a decay indeed be observed. For proton-pair adding, strong transitions to excited 0{sup +} states had been observed in the Te isotopes by Alford et al. [Nucl. Phys. A 323, 339 (1979)], indicating a breaking of the BCS approximation for protons in the ground state. We measured the neutron-pair removing (p,t) reaction on {sup 130}Te and found no indication of a corresponding splitting of the BCS nature of the ground state for neutrons.

  9. Systematic study of doping dependence on linear magnetoresistance in p-PbTe

    SciTech Connect (OSTI)

    Schneider, J. M.; Chitta, V. A.; Oliveira, N. F.; Peres, M. L. Castro, S. de; Soares, D. A. W.; Wiedmann, S.; Zeitler, U.; Abramof, E.; Rappl, P. H. O.; Mengui, U. A.

    2014-10-20

    We report on a large linear magnetoresistance effect observed in doped p-PbTe films. While undoped p-PbTe reveals a sublinear magnetoresistance, p-PbTe films doped with BaF{sub 2} exhibit a transition to a nearly perfect linear magnetoresistance behaviour that is persistent up to 30?T. The linear magnetoresistance slope ?R/?B is to a good approximation, independent of temperature. This is in agreement with the theory of Quantum Linear Magnetoresistance. We also performed magnetoresistance simulations using a classical model of linear magnetoresistance. We found that this model fails to explain the experimental data. A systematic study of the doping dependence reveals that the linear magnetoresistance response has a maximum for small BaF{sub 2} doping levels and diminishes rapidly for increasing doping levels. Exploiting the huge impact of doping on the linear magnetoresistance signal could lead to new classes of devices with giant magnetoresistance behavior.

  10. Ba{sub 2}TeO as an optoelectronic material: First-principles study

    SciTech Connect (OSTI)

    Sun, Jifeng; Shi, Hongliang; Du, Mao-Hua; Singh, David J.; Siegrist, Theo

    2015-05-21

    The band structure, optical, and defects properties of Ba{sub 2}TeO are systematically investigated using density functional theory with a view to understanding its potential as an optoelectronic or transparent conducting material. Ba{sub 2}TeO crystallizes with tetragonal structure (space group P4/nmm) and with a 2.93?eV optical bandgap [Besara et al., J. Solid State Chem. 222, 60 (2015)]. We find relatively modest band masses for both electrons and holes suggesting applications. Optical properties show infrared-red absorption when doped. This could potentially be useful for combining wavelength filtering and transparent conducting functions. Furthermore, our defect calculations show that Ba{sub 2}TeO is intrinsically p-type conducting under Ba-poor condition. However, the spontaneous formation of the donor defects may constrain the p-type transport properties and would need to be addressed to enable applications.

  11. Simulation of Electric Field in Semi Insulating Au/CdTe/Au Detector under Flux

    SciTech Connect (OSTI)

    Franc, J.; James, R.; Grill, R.; Kubat, J.; Belas, E.; Hoschl, P.; Moravec, P.; Praus, P.

    2009-08-02

    We report our simulations on the profile of the electric field in semi insulating CdTe and CdZnTe with Au contacts under radiation flux. The type of the space charge and electric field distribution in the Au/CdTe/Au structure is at high fluxes result of a combined influence of charge formed due to band bending at the electrodes and from photo generated carriers, which are trapped at deep levels. Simultaneous solution of drift-diffusion and Poisson equations is used for the calculation. We show, that the space charge originating from trapped photo-carriers starts to dominate at fluxes 10{sup 15}-10{sup 16}cm{sup -2}s{sup -1}, when the influence of contacts starts to be negligible.

  12. Search for contact interactions in ???? events in pp collisions at ?s=7 TeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chatrchyan, S.; Khachatryan, V.; Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Aguilo, E.; Bergauer, T.; Dragicevic, M.; Erö, J.; Fabjan, C.; et al

    2013-02-01

    Results are reported from a search for the effects of contact interactions using events with a high-mass, oppositely charged muon pair. The events are collected in proton-proton collisions at s?=7 TeV using the Compact Muon Solenoid detector at the Large Hadron Collider. The data sample corresponds to an integrated luminosity of 5.3 fb?¹. The observed dimuon mass spectrum is consistent with that expected from the standard model. The data are interpreted in the context of a quark- and muon-compositeness model with a left-handed isoscalar current and an energy scale parameter ?. The 95% confidence level lower limit on ? ismore »9.5 TeV under the assumption of destructive interference between the standard model and contact-interaction amplitudes. For constructive interference, the limit is 13.1 TeV. These limits are comparable to the most stringent ones reported to date.« less

  13. Search for contact interactions in ???? events in pp collisions at ?s=7 TeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chatrchyan, S.; Khachatryan, V.; Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Aguilo, E.; Bergauer, T.; Dragicevic, M.; Erö, J.; Fabjan, C.; Friedl, M.; Frühwirth, R.; Ghete, V. M.; Hammer, J.; Hörmann, N.; Hrubec, J.; Jeitler, M.; Kiesenhofer, W.; Knünz, V.; Krammer, M.; Krätschmer, I.; Liko, D.; Mikulec, I.; Pernicka, M.; Rahbaran, B.; Rohringer, C.; Rohringer, H.; Schöfbeck, R.; Strauss, J.; Taurok, A.; Waltenberger, W.; Walzel, G.; Widl, E.; Wulz, C.-E.; Mossolov, V.; Shumeiko, N.; Suarez Gonzalez, J.; Bansal, M.; Bansal, S.; Cornelis, T.; De Wolf, E. A.; Janssen, X.; Luyckx, S.; Mucibello, L.; Ochesanu, S.; Roland, B.; Rougny, R.; Selvaggi, M.; Staykova, Z.; Van Haevermaet, H.; Van Mechelen, P.; Van Remortel, N.; Van Spilbeeck, A.; Blekman, F.; Blyweert, S.; D’Hondt, J.; Gonzalez Suarez, R.; Kalogeropoulos, A.; Maes, M.; Olbrechts, A.; Van Doninck, W.; Van Mulders, P.; Van Onsem, G. P.; Villella, I.; Clerbaux, B.; De Lentdecker, G.; Dero, V.; Gay, A. P. R.; Hreus, T.; Léonard, A.; Marage, P. E.; Mohammadi, A.; Reis, T.; Thomas, L.; Vander Marcken, G.; Vander Velde, C.; Vanlaer, P.; Wang, J.; Adler, V.; Beernaert, K.; Cimmino, A.; Costantini, S.; Garcia, G.; Grunewald, M.; Klein, B.; Lellouch, J.; Marinov, A.; Mccartin, J.; Ocampo Rios, A. A.; Ryckbosch, D.; Strobbe, N.; Thyssen, F.; Tytgat, M.; Verwilligen, P.; Walsh, S.; Yazgan, E.; Zaganidis, N.; Basegmez, S.; Bruno, G.; Castello, R.; Ceard, L.; Delaere, C.; du Pree, T.; Favart, D.; Forthomme, L.; Giammanco, A.; Hollar, J.; Lemaitre, V.; Liao, J.; Militaru, O.; Nuttens, C.; Pagano, D.; Pin, A.; Piotrzkowski, K.; Schul, N.; Vizan Garcia, J. M.; Beliy, N.; Caebergs, T.; Daubie, E.; Hammad, G. H.; Alves, G. A.; Correa Martins Junior, M.; De Jesus Damiao, D.; Martins, T.; Pol, M. E.; Souza, M. H. G.; Aldá Júnior, W. L.; Carvalho, W.; Custódio, A.; Da Costa, E. M.; De Oliveira Martins, C.; Fonseca De Souza, S.; Matos Figueiredo, D.; Mundim, L.; Nogima, H.; Oguri, V.; Prado Da Silva, W. L.; Santoro, A.; Soares Jorge, L.; Sznajder, A.; Anjos, T. S.; Bernardes, C. A.; Dias, F. A.; Fernandez Perez Tomei, T. R.; Gregores, E. M.; Lagana, C.; Marinho, F.; Mercadante, P. G.; Novaes, S. F.; Padula, Sandra S.; Genchev, V.; Iaydjiev, P.; Piperov, S.; Rodozov, M.; Stoykova, S.; Sultanov, G.; Tcholakov, V.; Trayanov, R.; Vutova, M.; Dimitrov, A.; Hadjiiska, R.; Kozhuharov, V.; Litov, L.; Pavlov, B.; Petkov, P.; Bian, J. G.; Chen, G. M.; Chen, H. S.; Jiang, C. H.; Liang, D.; Liang, S.; Meng, X.; Tao, J.; Wang, J.; Wang, X.; Wang, Z.; Xiao, H.; Xu, M.; Zang, J.; Zhang, Z.; Asawatangtrakuldee, C.; Ban, Y.; Guo, S.; Guo, Y.; Li, W.; Liu, S.; Mao, Y.; Qian, S. J.; Teng, H.; Wang, D.; Zhang, L.; Zhu, B.; Zou, W.; Avila, C.; Gomez, J. P.; Gomez Moreno, B.; Osorio Oliveros, A. F.; Sanabria, J. C.; Godinovic, N.; Lelas, D.; Plestina, R.; Polic, D.; Puljak, I.; Antunovic, Z.; Kovac, M.; Brigljevic, V.; Duric, S.; Kadija, K.; Luetic, J.; Morovic, S.; Attikis, A.; Galanti, M.; Mavromanolakis, G.; Mousa, J.; Nicolaou, C.; Ptochos, F.; Razis, P. A.; Finger, M.; Finger, M.; Assran, Y.; Elgammal, S.; Ellithi Kamel, A.; Mahmoud, M. A.; Radi, A.; Kadastik, M.; Müntel, M.; Raidal, M.; Rebane, L.; Tiko, A.; Eerola, P.; Fedi, G.; Voutilainen, M.; Härkönen, J.; Heikkinen, A.; Karimäki, V.; Kinnunen, R.; Kortelainen, M. J.; Lampén, T.; Lassila-Perini, K.; Lehti, S.; Lindén, T.; Luukka, P.; Mäenpää, T.; Peltola, T.; Tuominen, E.; Tuominiemi, J.; Tuovinen, E.; Ungaro, D.; Wendland, L.; Banzuzi, K.; Karjalainen, A.; Korpela, A.; Tuuva, T.; Besancon, M.; Choudhury, S.; Dejardin, M.; Denegri, D.; Fabbro, B.; Faure, J. L.; Ferri, F.; Ganjour, S.; Givernaud, A.; Gras, P.; Hamel de Monchenault, G.; Jarry, P.; Locci, E.; Malcles, J.; Millischer, L.; Nayak, A.; Rander, J.; Rosowsky, A.; Shreyber, I.; Titov, M.; Baffioni, S.; Beaudette, F.; Benhabib, L.; Bianchini, L.; Bluj, M.; Broutin, C.; Busson, P.; Charlot, C.; Daci, N.; Dahms, T.; Dobrzynski, L.; Granier de Cassagnac, R.; Haguenauer, M.; Miné, P.; Mironov, C.; Naranjo, I. N.; Nguyen, M.; Ochando, C.; Paganini, P.; Sabes, D.; Salerno, R.; Sirois, Y.; Veelken, C.; Zabi, A.; Agram, J.-L.; Andrea, J.; Bloch, D.; Bodin, D.; Brom, J.-M.; Cardaci, M.; Chabert, E. C.; Collard, C.; Conte, E.; Drouhin, F.; Ferro, C.; Fontaine, J.-C.; Gelé, D.; Goerlach, U.; Juillot, P.; Le Bihan, A.-C.; Van Hove, P.; Fassi, F.; Mercier, D.; Beauceron, S.; Beaupere, N.; Bondu, O.; Boudoul, G.; Chasserat, J.; Chierici, R.; Contardo, D.; Depasse, P.; El Mamouni, H.; Fay, J.; Gascon, S.; Gouzevitch, M.; Ille, B.; Kurca, T.; Lethuillier, M.; Mirabito, L.; Perries, S.; Sordini, V.; Tschudi, Y.; Verdier, P.; Viret, S.; Tsamalaidze, Z.; Anagnostou, G.; Beranek, S.; Edelhoff, M.; Feld, L.; Heracleous, N.; Hindrichs, O.; Jussen, R.; Klein, K.; Merz, J.

    2013-02-01

    Results are reported from a search for the effects of contact interactions using events with a high-mass, oppositely charged muon pair. The events are collected in proton-proton collisions at s?=7 TeV using the Compact Muon Solenoid detector at the Large Hadron Collider. The data sample corresponds to an integrated luminosity of 5.3 fb?¹. The observed dimuon mass spectrum is consistent with that expected from the standard model. The data are interpreted in the context of a quark- and muon-compositeness model with a left-handed isoscalar current and an energy scale parameter ?. The 95% confidence level lower limit on ? is 9.5 TeV under the assumption of destructive interference between the standard model and contact-interaction amplitudes. For constructive interference, the limit is 13.1 TeV. These limits are comparable to the most stringent ones reported to date.

  14. ,Jet)TE( 0 0.5 1 1.5 2 2.5 3

    E-Print Network [OSTI]

    Quigg, Chris

    #12;1b _ 1b g g g 0 1 0 1 _ _ b b b b _ q q #12;#12;#12;#12;,Jet)TE( 0 0.5 1 1.5 2 2.5 3 TaggedJets 0 5 10 15 20 ,Jet)TE( 0 0.5 1 1.5 2 2.5 3 TaggedJets 0 5 10 15 20 Data QCD-multijet Top W/Z+jets,Diboson -1 CDF Run II Preliminary, 156pb b1b ~ Search for Gluino Jet) st ,1TE( 0 0.5 1 1.5 2 2.5 3 TaggedJets

  15. SE HAN FINALIZADO LOS PREPARATIVOS PARA LA CONFERENCIA NACIONAL DE JUSTICIA MEDIOAMBIENTAL Y PROGRAMA DE FORMACIÓN 2013

    Broader source: Energy.gov [DOE]

    La National Environmental Justice Conference, Inc. (Conferencia de Justicia Medioambiental) se prepara para otro exitoso acontecimiento, ya que se aproxima la Conferencia Nacional de Justicia...

  16. Thermoelectric study of crossroads material MnTe via sulfur doping

    SciTech Connect (OSTI)

    Xie, Wenjie Populoh, Sascha; Sagarna, Leyre; Trottmann, Matthias; Ga??zka, Krzysztof; Xiao, Xingxing; Liu, Yufei; He, Jian; Weidenkaff, Anke

    2014-03-14

    Here, we report thermoelectric study of crossroads material MnTe via iso-electronic doping S on the Te-site. MnTe{sub 1-x}S{sub x} samples with nominal S content of x?=?0.00, 0.05, and 0.10 were prepared using a melt-quench method followed by pulverization and spark plasma sintering. The X-ray powder diffraction, scanning electron microscopy, and ZAF-corrected compositional analysis confirmed that S uniformly substitutes Te up to slightly over 2%. A higher content of S in the starting materials led to the formation of secondary phases. The thermoelectric properties of MnTe{sub 1-x}S{sub x} samples were characterized by means of Seebeck coefficient, electrical conductivity, and thermal conductivity measurements from 300?K to 773?K. Furthermore, Hall coefficient measurements and a single parabolic band model were used to help gain insights on the effects of S-doping on the scattering mechanism and the carrier effective mass. As expected, S doping not only introduced hole charge carriers but also created short-range defects that effectively scatter heat-carrying phonons at elevated temperatures. On the other hand, we found that S doping degraded the effective mass. As a result, the ZT of MnTe{sub 0.9}S{sub 0.1} was substantially enhanced over the pristine sample near 400?K, while the improvement of ZT became marginal at elevated temperatures. A ZT???0.65 at 773?K was obtained in all three samples.

  17. 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

  18. Gate-Defined Wires in HgTe Quantum Wells: From Majorana Fermions to Spintronics Johannes Reuther and Jason Alicea

    E-Print Network [OSTI]

    Yacoby, Amir

    Gate-Defined Wires in HgTe Quantum Wells: From Majorana Fermions to Spintronics Johannes Reuther and various spintronics applications based on gate-defined wires in HgTe quantum wells. Because of the Dirac­15] architectures, while not usually viewed from a spintronics lens, similarly rely crucially on spin manipulation

  19. Binary Alloys of Ge and Te: Order, Voids, and the Eutectic Composition J. Akola1,2

    E-Print Network [OSTI]

    important roles in modern computers (DVD-RAM) and electronic devices (rewritable optical disks DVD-RW hybridization) in `-Ge0:15Te0:85 [15]. Recently we reported DF calculations of the Ge2Sb2Te5 (GST) alloy

  20. 28th International Cosmic Ray Conference 2269 Preliminary Evidence for TeV Gamma Ray Emission from

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    28th International Cosmic Ray Conference 2269 Preliminary Evidence for TeV Gamma Ray Emission from of view results in a higher sensitivity to the diffuse emission from the galaxy com- pared to previous experiments in the same energy band. Preliminary evidence for TeV gamma emission from the galactic plane using

  1. Sonochemical and hydrothermal synthesis of PbTe nanostructures with the aid of a novel capping agent

    SciTech Connect (OSTI)

    Fard-Fini, Shahla Ahmadian; Salavati-Niasari, Masoud; Mohandes, Fatemeh

    2013-10-15

    Graphical abstract: - Highlights: • PbTe nanostructures were prepared with the aid of Schiff-base compound. • Sonochemical and hydrothermal methods were employed to fabricate PbTe nanostrucrues. • The effect of preparation parameters on the morphology of PbTe was investigated. - Abstract: In this work, a new Schiff-base compound derived from 1,8-diamino-3,6-dioxaoctane and 2-hydroxy-1-naphthaldehyde marked as (2-HyNa)-(DaDo) was synthesized, characterized, and then used as capping agent for the preparation of PbTe nanostructures. To fabricate PbTe nanostructures, two different synthesis methods; hydrothermal and sonochemical routes, were applied. To further investigate, the effect of preparation parameters like reaction time and temperature in hydrothermal synthesis and sonication time in the presence of ultrasound irradiation on the morphology and purity of the final products was tested. The products were analyzed with the aid of SEM, TEM, XRD, FT-IR, and EDS. Based on the obtained results, it was found that pure cubic phased PbTe nanostructures have been obtained by hydrothermal and sonochemical approaches. Besides, SEM images showed that cubic-like and rod-like PbTe nanostructures have been formed by hydrothermal and sonochemical methods, respectively. Sonochemical synthesis of PbTe nanostructures was favorable, because the synthesis time of sonochemical method was shorter than that of hydrothermal method.

  2. CdTe/CdS solar cells on flexible substrates Xavier Mathew a,*, J. Pantoja Enriquez a

    E-Print Network [OSTI]

    Romeo, Alessandro

    CdTe/CdS solar cells on flexible substrates Xavier Mathew a,*, J. Pantoja Enriquez a , Alessandro of CdTe/CdS solar cells on flexible substrates is reviewed in this article. Photovoltaic structures. The specific power of the solar cells is an important factor in space applications and hence development

  3. Study of W boson production in pPb collisions at sNN=5.02 TeV...

    Office of Scientific and Technical Information (OSTI)

    Study of W boson production in pPb collisions at sNN5.02 TeV Citation Details In-Document Search Title: Study of W boson production in pPb collisions at sNN5.02 TeV Publication...

  4. Solar Energy Materials & Solar Cells 90 (2006) 34073415 High-efficiency flexible CdTe solar cells

    E-Print Network [OSTI]

    Romeo, Alessandro

    2006-01-01

    Solar Energy Materials & Solar Cells 90 (2006) 3407­3415 High-efficiency flexible CdTe solar cells: Solar cells; Thin films; CdTe; Flexible solar cells; Space solar cells; Solar energy ARTICLE IN PRESS for Renewable Energy Systems and Technology), Department of Electronic and Electrical Engineering, Loughborough

  5. Probing the size and environment induced phase transformation in CdSe quantum dots

    SciTech Connect (OSTI)

    Karakoti, Ajay S.; Sanghavi, Shail P.; Nachimuthu, Ponnusamy; Yang, Ping; Thevuthasan, Suntharampillai

    2011-11-17

    The structural and electronic properties of CdSe quantum dots in toluene and drop-casted on Si wafer were investigated by in-situ micro X-ray diffraction, X-ray photoelectron spectroscopy and UV-Vis absorption and emission spectroscopy. The in-situ micro diffraction data show that the CdSe quantum dots capped with TOPO or hexadecylamine (HDA) in toluene exhibit predominantly wurtzite crystal structure, which undergoes a phase transformation to zinc blende crystal structure following drop casting on Si and this phase transition increases with decreasing the size of the CdSe quantum dots. Decreasing the size of quantum dots also increases the Se vacancies that facilitate the phase transformation. The X-ray photoelectron spectra show a systematic increase in the core level binding energies of Cd 3d and Se 3d, the band gap and the Cd/Se ratio as the size of the quantum dots decreases from 6.6nm to 2.1nm. This is attributed to the quantum confinement of CdSe crystallites by the capping ligands in toluene which increases with decreasing the size of the quantum dots. However, drop-casting quantum dots on Si alter the density and arrangement of capping ligands and solvent molecules on the quantum dots which causes significant phase transformation.

  6. INCOSE Systems Engineering Handbook v3.2: Improving the Process for SE Practitioners

    SciTech Connect (OSTI)

    R. Douglas Hamelin; David D. Walden; Michael E. Krueger

    2010-07-01

    The INCOSE Systems Engineering Handbook is the official INCOSE reference document for understanding systems engineering (SE) methods and conducting SE activities. Over the years, the Handbook has evolved to accommodate advances in the SE discipline and now serves as the basis for the Certified Systems Engineering Professional (CSEP) exam. Due to its evolution, the Handbook had become somewhat disjointed in its treatment and presentation of SE topics and was not aligned with the latest version of International Organization for Standardization (ISO)/International Electrotechnical Commission (IEC) 15288:2008, Systems and Software Engineering. As a result, numerous inconsistencies were identified that could confuse practitioners and directly impact the probability of success in passing the CSEP exam. Further, INCOSE leadership had previously submitted v3.1 of the Handbook to ISO/IEC for consideration as a Technical Report, but was told that the Handbook would have to be updated to conform with the terminology and structure of new ISO/IEC15288:2008, Systems and software engineering, prior to being considered. The revised INCOSE Systems Engineering Handbook v3.2 aligns with the structure and principles of ISO/IEC 15288:2008 and presents the generic SE life-cycle process steps in their entirety, without duplication or redundancy, in a single location within the text. As such, the revised Handbook v3.2 serves as a comprehensive instructional and reference manual for effectively understanding SE processes and conducting SE and better serves certification candidates preparing for the CSEP exam.

  7. NuTeV cross-section and structure function measurements

    SciTech Connect (OSTI)

    Donna Naples et al.

    2003-12-10

    The NuTeV experiment has obtained a unique high statistics sample of neutrino and antineutrino interactions using its high-energy sign-selected beam. Charged-current {nu} and {bar {nu}} differential cross sections are extracted. Neutrino-Iron structure functions, F{sub 2}(x, Q{sup 2}) and xF{sub 3}(x, Q{sup 2}), are determined by fitting the y-dependence of the differential cross sections. NuTeV has precise understanding of its hadron and muon energy scales, which improves the systematic precision of this measurement.

  8. Renaissance of the ~1 TeV Fixed-Target Program

    SciTech Connect (OSTI)

    Adams, T.; Appel, Jeffrey A.; Arms, Kregg Elliott; Balantekin, A.B.; Conrad, Janet Marie; Cooper, Peter S.; Djurcic, Zelimir; Dunwoodie, William M.; Engelfried, Jurgen; Fisher, Peter H.; Gottschalk, E.; /Fermilab /Northwestern U.

    2009-05-01

    This document describes the physics potential of a new fixed-target program based on a {approx} TeV proton source. Two proton sources are potentially available in the future: the existing Tevatron at Fermilab, which can provide 800 GeV protons for fixed-target physics, and a possible upgrade to the SPS at CERN, called SPS+, which would produce 1 TeV protons on target. In this paper we use an example Tevatron fixed-target program to illustrate the high discovery potential possible in the charm and neutrino sectors. We highlight examples which are either unique to the program or difficult to accomplish at other venues.

  9. Renaissance of the ~ 1-TeV Fixed-Target Program

    SciTech Connect (OSTI)

    Adams, T.; Appel, J.A.; Arms, K.E.; Balantekin, A.B.; Conrad, J.M.; Cooper, P.S.; Djurcic, Z.; Dunwoodie, W.; Engelfried, J.; Fisher, P.H.; Gottschalk, Erik Edward; de Gouvea, A.; Heller, K.; Ignarra, C.M.; Karagiorgi, G.; Kwan, S.; Loinaz, W.A.; Meadows, B.; Moore, R.; Morfin, J.G.; Naples, D.; /Pittsburgh U. /St. Mary's Coll., Minnesota /New Mexico State U. /Michigan U. /Wayne State U. /South Carolina U. /Florida U. /Carnegie Mellon U. /Cincinnati U. /Columbia U. /Columbia U. /Northwestern U. /Yale U. /Fermilab /Argonne /Northwestern U. /APC, Paris

    2011-12-02

    This document describes the physics potential of a new fixed-target program based on a {approx}1 TeV proton source. Two proton sources are potentially available in the future: the existing Tevatron at Fermilab, which can provide 800 GeV protons for fixed-target physics, and a possible upgrade to the SPS at CERN, called SPS+, which would produce 1 TeV protons on target. In this paper we use an example Tevatron fixed-target program to illustrate the high discovery potential possible in the charm and neutrino sectors. We highlight examples which are either unique to the program or difficult to accomplish at other venues.

  10. Fast variability of TeV gamma-rays from the radio galaxy M 87

    E-Print Network [OSTI]

    HESS Collaboration; F. A. Aharonian

    2006-12-01

    The detection of fast variations of the TeV (10^12 eV) gamma-ray flux, on time-scales of days, from the nearby radio galaxy M 87 is reported. These variations are ~10 times faster than that observed in any other waveband and imply a very compact emission region with a dimension similar to the Schwarzschild radius of the central black hole. We thus can exclude several other sites and processes of the gamma-ray production. The observations confirm that TeV gamma-rays are emitted by extragalactic sources other than blazars, where jets are not relativistically beamed towards the observer.

  11. Shubnikov-de Haas Oscillations in the Bulk Rashba Semiconductor BiTeI

    SciTech Connect (OSTI)

    Bell, C.; Bahramy, M.S.; Murakawa, H.; Checkelsky, J.G.; Arita, R.; Kaneko, Y.; Onose, Y.; Nagaosa, N.; Tokura, Y.; Hwang, H.Y.

    2012-07-11

    Bulk magnetoresistance quantum oscillations are observed in high quality single crystal samples of BiTeI. This compound shows an extremely large internal spin-orbit coupling, associated with the polarity of the alternating Bi, Te, and I layers perpendicular to the c-axis. The corresponding areas of the inner and outer Fermi surfaces around the A-point show good agreement with theoretical calculations, demonstrating that the intrinsic bulk Rashba-type splitting is nearly 360 meV, comparable to the largest spin-orbit coupling generated in heterostructures and at surfaces.

  12. Preliminary design for a 20 TeV Collider in a deep tunnel at Fermilab

    SciTech Connect (OSTI)

    Not Available

    1985-01-12

    The Reference Design Study for a 20 TeV Collider demonstrated the technical and cost feasibility of a 20 TeV superconducting collider facility. Based on magnets of 3T, 5T, and 6.5T the Main Ring of the Collider would have a circumference of 164 km, 113 km, or 90 km. There would be six collision regions, of which four would be developed intially. The 5T and 6.5T rings would have twelve major refrigeration stations, while the 3T design would have 24 major refrigeration stations.

  13. Characterization of ZnSe scintillating bolometers for Double Beta Decay

    E-Print Network [OSTI]

    C. Arnaboldi; S. Capelli; O. Cremonesi; L. Gironi; M. Pavan; G. Pessina; S. Pirro

    2010-06-30

    ZnSe scintillating bolometers are good candidates for future Double Beta Decay searches, because of the 82Se high Q-value and thanks to the possibility of alpha background rejection on the basis of the scintillation signal. In this paper we report the characteristics and the anomalies observed in an extensive study of these devices. Among them, an unexpected high emission from alpha particles, accompanied with an unusual pattern of the light vs. heat scatter plot. The perspectives for the application of this kind of detectors to search for the Neutrinoless Double Beta Decay of 82Se are presented.

  14. Ann bay lodyans 11 / Se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01

    Liben”) ki pare ti liv sa a. [Lawrence, Kan.] : Institute of Haitian Studies ; [Port-au-Prince] : Bon Nouvèl : Fondasyon Alfa Lwès, 2000. Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml ANN BAY LODYANS 11 Se Bryant Freeman ("Tonton Liben...") ki pare ti liv sa a. AYITI SE PEP AYISYEN PM 7854 .H39 A56 2000 PM Enstiti Etid Ayisyen - Inivesite Kannzas Bon Nouvel Fondasyon Alfa Lwes 1997 YON PWASON KI RELE TEZEN Vwala se yon jennfi yo rele Wozilya ak yon jennjan yo rele Tezen ki...

  15. Ann bay lodyans 14 / Se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01

    Liben”) ki pare ti liv sa a. [Lawrence, Kan.] : Institute of Haitian Studies ; [Port-au-Prince] : Bon Nouvèl : Fondasyon Alfa Lwès, 2000. Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml fcjNlVfcHto" r ' K A N S A S L lBf iAH.r ANN BAY... LODYANS1 4 Se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a. A 51* AYITI SE PEP AYISYEN PM 7854 .H39 A56 2000 v. 14 Enstiti Etid Ayisyen - Inivesite Kannzas Bon Nouvel Fondasyon Alfa Lwes 2000 YON TI PYE ZORANJ Se istwa yon ti fi ki...

  16. TeV GAMMA-RAY SURVEY OF THE NORTHERN HEMISPHERE SKY USING THE MILAGRO OBSERVATORY R. Atkins,1,2

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    to search the entire northern hemisphere for such objects. The search for short bursts of TeV gamma rays hasTeV GAMMA-RAY SURVEY OF THE NORTHERN HEMISPHERE SKY USING THE MILAGRO OBSERVATORY R. Atkins,1,2 W) are presented. The data have been searched for steady point sources of TeV gamma rays between declinations of 1

  17. Lattice dynamics of BaFe2X3(X=S,Se) compounds

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Popovi?, Z. V.; Š?epanovi?, M.; Lazarevi?, N.; Opa?i?, M.; Radonji?, M. M.; Tanaskovi?, D.; Lei, Hechang; Petrovic, C.

    2015-02-27

    We present the Raman scattering spectra of the S=2 spin ladder compounds BaFe?X? (X=S,Se) in a temperature range between 20 and 400 K. Although the crystal structures of these two compounds are both orthorhombic and very similar, they are not isostructural. The unit cell of BaFe?S? (BaFe?Se?) is base-centered Cmcm (primitive Pnma), giving 18 (36) modes to be observed in the Raman scattering experiment. We have detected almost all Raman active modes, predicted by factor group analysis, which can be observed from the cleavage planes of these compounds. Assignment of the observed Raman modes of BaFe?S(Se)? is supported by themore »lattice dynamics calculations. The antiferromagnetic long-range spin ordering in BaFe?Se? below TN=255K leaves a fingerprint both in the A1g and B3g phonon mode linewidth and energy.« less

  18. Low-temperature ferromagnetic properties in Co-doped Ag{sub 2}Se nanoparticles

    SciTech Connect (OSTI)

    Yang, Fengxia E-mail: xia9020@hust.edu.cn; Yu, Gen; Han, Chong; Liu, Tingting; Zhang, Duanming; Xia, Zhengcai E-mail: xia9020@hust.edu.cn

    2014-01-06

    ?-Ag{sub 2}Se is a topologically nontrivial insulator. The magnetic properties of Co-doped Ag{sub 2}Se nanoparticles with Co concentrations up to 40% were investigated. The cusp of zero-field-cooling magnetization curves and the low-temperature hysteresis loops were observed. With increasing concentration of Co{sup 2+} ions mainly substituting Ag{sub I} sites in the Ag{sub 2}Se structure, the resistivity, Curie temperature T{sub c}, and magnetization increased. At 10?T, a sharp drop of resistance near T{sub c} was detected due to Co dopants. The ferromagnetic behavior in Co-doped Ag{sub 2}Se might result from the intra-layer ferromagnetic coupling and surface spin. This magnetic semiconductor is a promising candidate in electronics and spintronics.

  19. Enhanced Thermoelectric Power and Electronic Correlations in RuSe2

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, Kefeng; Wang, Aifeng; Tomic, A.; Wang, Limin; Abeykoon, A.M. Milinda; Dooryhee, E.; Billinge, S. J.L.; Petrovic, C.

    2015-04-01

    We report the electronic structure, electric and thermal transport properties of Ru1-xIrxSe2 (x ? 0:2). RuSe2 is a semiconductor that crystallizes in a cubic pyrite unit cell. The Seebeck coefficient of RuSe2 exceeds -200 ?#22;V/K around 730 K. Ir substitution results in the suppression of the resistivity and the Seebeck coefficient, suggesting the removal of the peaks in density of states near the Fermi level. Ru0.8Ir0.2Se2 shows a semiconductor-metal crossover at about 30 K. The magnetic field restores the semiconducting behavior. Our results indicate the importance of the electronic correlations in enhanced thermoelectricity of RuSb2.

  20. Phonon properties of BaFe?X? (X=S, Se) spin ladder compounds

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Popovicq, Z. V.; Petrovic, C.; Scepanovic, M.; Lazarevic, N.; Opacic, M.; Radonjic, M. M.; Tanaskovic, D.; Lei, Hechang

    2015-02-27

    We present the Raman scattering spectra of the S=2 spin ladder compounds BaFe?X? (X=S,Se) in a temperature range between 20 and 400 K. Although the crystal structures of these two compounds are both orthorhombic and very similar, they are not isostructural. The unit cell of BaFe?S? (BaFe?Se?) is base-centered Cmcm (primitive Pnma), giving 18 (36) modes to be observed in the Raman scattering experiment. We have detected almost all Raman active modes, predicted by factor group analysis, which can be observed from the cleavage planes of these compounds. Assignment of the observed Raman modes of BaFe?S(Se)? is supported by themore »lattice dynamics calculations. The antiferromagnetic long-range spin ordering in BaFe?Se? below TN=255K leaves a fingerprint both in the A1g and B3g phonon mode linewidth and energy.« less

  1. Super-Poissonian Statistics of Photon Emission from Single CdSe...

    Office of Scientific and Technical Information (OSTI)

    Super-Poissonian Statistics of Photon Emission from Single CdSe-CdS Core-Shell Nanocrystals Coupled to Metal Nanostructures Citation Details In-Document Search Title:...

  2. Time resolved fluorescence of CdSe nanocrystals using single molecule spectroscopy

    E-Print Network [OSTI]

    Fisher, Brent R

    2005-01-01

    A wide variety of spectroscopic studies of CdSe nanocrystals (NCs) are presented in this thesis, all studying some aspect of the temporal evolution of NC fluorescence tinder different conditions. In particular the methods ...

  3. Efficient light emitting devices utilizing CdSe(ZnS) quantum dots in organic host matrices

    E-Print Network [OSTI]

    Coe-Sullivan, Seth (Seth Alexander)

    2002-01-01

    We demonstrate efficient electroluminescence from thin film structures containing core-shell CdSe(ZnS) quantum dots dispersed in molecular organic host materials. In the most efficient devices, excitons are created on the ...

  4. WEATHERIZATION INDUSTRIES SAVE ENERGY ST SE SALEM, OREGON 97301 (503) 5691381 WEATHERIZATIONALLIES@GMAIL.COM

    E-Print Network [OSTI]

    WEATHERIZATION INDUSTRIES SAVE ENERGY 565 21ST ST SE SALEM, OREGON 97301 · (503) 5691381 AND CONSERVATION COUNCIL'S CONSERVATION PLANNING ASSUMPTIONS Weatherization Industries Save Energy (WISE · WEATHERIZATIONALLIES@GMAIL.COM COMMENTS ON ACHIEVABLE SAVINGS: A RETROSPECTIVE LOOK AT THE NORTHWEST POWER

  5. Hidden Superlattice in Tl2(SC6H4S) and Tl2(SeC6H4Se) Solved from Powder X-ray Diffraction

    SciTech Connect (OSTI)

    K Stone; D Turner; M Singh; T Vaid; P Stephens

    2011-12-31

    The crystal structures of the isostructural title compounds poly[({mu}-benzene-1,4-dithiolato)dithallium], Tl{sub 2}(SC{sub 6}H{sub 4}S), and poly[({mu}-benzene-1,4-diselenolato)dithallium], Tl{sub 2}(SeC{sub 6}H{sub 4}Se), were solved by simulated annealing from high-resolution synchrotron X-ray powder diffraction. Rietveld refinements of an initial structure with one formula unit per triclinic cell gave satisfactory agreement with the data, but led to a structure with impossibly close non-bonded contacts. A disordered model was proposed to alleviate this problem, but an alternative supercell structure leads to slightly improved agreement with the data. The isostructural superlattice structures were confirmed for both compounds through additional data collection, with substantially better counting statistics, which revealed the presence of very weak superlattice peaks not previously seen. Overall, each structure contains Tl-S or Tl-Se two-dimensional networks, connected by phenylene bridges. The sulfur (or selenium) coordination sphere around each thallium is a highly distorted square pyramid or a 'see-saw' shape, depending upon how many Tl-S or Tl-Se interactions are considered to be bonds. In addition, the two compounds contain pairs of Tl{sup I} ions that interact through a closed-shell 'thallophilic' interaction: in the sulfur compound there are two inequivalent pairs of Tl atoms with Tl-Tl distances of 3.49 and 3.58 {angstrom}, while in the selenium compound those Tl-Tl interactions are at 3.54 and 3.63 {angstrom}.

  6. Unique Challenges Accompany Thick-Shell CdSe/nCdS (n > 10) Nanocrystal Synthesis

    SciTech Connect (OSTI)

    Guo, Y; Marchuk, K; Abraham, R; Sampat, S; Abraham, R.; Fang, N; Malko, AV; Vela, J

    2011-12-23

    Thick-shell CdSe/nCdS (n {ge} 10) nanocrystals were recently reported that show remarkably suppressed fluorescence intermittency or 'blinking' at the single-particle level as well as slow rates of Auger decay. Unfortunately, whereas CdSe/nCdS nanocrystal synthesis is well-developed up to n {le} 6 CdS monolayers (MLs), reproducible syntheses for n {ge} 10 MLs are less understood. Known procedures sometimes result in homogeneous CdS nucleation instead of heterogeneous, epitaxial CdS nucleation on CdSe, leading to broad and multimodal particle size distributions. Critically, obtained core/shell sizes are often below those desired. This article describes synthetic conditions specific to thick-shell growth (n {ge} 10 and n {ge} 20 MLs) on both small (sub2 nm) and large (>4.5 nm) CdSe cores. We find added secondary amine and low concentration of CdSe cores and molecular precursors give desired core/shell sizes. Amine-induced, partial etching of CdSe cores results in apparent shell-thicknesses slightly beyond those desired, especially for very-thick shells (n {ge} 20 MLs). Thermal ripening and fast precursor injection lead to undesired homogeneous CdS nucleation and incomplete shell growth. Core/shells derived from small CdSe (1.9 nm) have longer PL lifetimes and more pronounced blinking at single-particle level compared with those derived from large CdSe (4.7 nm). We expect our new synthetic approach will lead to a larger throughput of these materials, increasing their availability for fundamental studies and applications.

  7. Proton structure from multiparticle contribution to elastic pp-scattering at 7 TeV

    E-Print Network [OSTI]

    Heller, Barbara

    Proton structure from multiparticle contribution to elastic pp-scattering at 7 TeV I.M. Dremin Lebedev Physical Institute, Moscow 119991, Russia The parton content of protons gets strong peripheral protons. The very first analyses [1, 2, 3] have lead to extremely interesting conclusions about

  8. SCIPP 99/12 Study of Active Galactic Nuclei at TeV Energies

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    and study transient sources. One of the primary goals is the search for, and study of, AGN at TeV energies, giving insight into particle acceleration mechanisms and providing information on the strength, 4, 5]. None of these BL Lacs are strong EGRET sources (1ES 2344+514 has in fact not been detected

  9. The Relic Neutralino Surface at a 100 TeV collider

    E-Print Network [OSTI]

    Joseph Bramante; Patrick J. Fox; Adam Martin; Bryan Ostdiek; Tilman Plehn; Torben Schell; Michihisa Takeuchi

    2015-03-27

    We map the parameter space for MSSM neutralino dark matter which freezes out to the observed relic abundance, in the limit that all superpartners except the neutralinos and charginos are decoupled. In this space of relic neutralinos, we show the dominant dark matter annihilation modes, the mass splittings among the electroweakinos, direct detection rates, and collider cross-sections. The mass difference between the dark matter and the next-to-lightest neutral and charged states is typically much less than electroweak gauge boson masses. With these small mass differences, the relic neutralino surface is accessible to a future 100 TeV hadron collider, which can discover inter-neutralino mass splittings down to 1 GeV and thermal relic dark matter neutralino masses up to 1.5 TeV with a few inverse attobarns of luminosity. This coverage is a direct consequence of the increased collider energy: the Standard Model events with missing transverse momentum in the TeV range have mostly hard electroweak radiation, distinct from the soft radiation shed in compressed electroweakino decays. We exploit this kinematic feature in final states including photons and leptons, tailored to the 100 TeV collider environment.

  10. New Loops! MiTeGen* 50MicroMountsTM consist of a thin microfabricated

    E-Print Network [OSTI]

    Meagher, Mary

    New Loops! MiTeGen* 50µMicroMountsTM consist of a thin microfabricated polyimide film attached to a solid non-magnetic stainless steel pin. The film is polyimide, which is used in Kapton® tape and is employed for X- ray transparent windows on X-ray beam lines. The film is curved by wrapping polyimide film

  11. First measurement of hadronic event shapes in pp collisions at ?s = 7 TeV

    E-Print Network [OSTI]

    CMS Collaboration

    Hadronic event shapes have been measured in proton–proton collisions at ?s =7 TeV, with a data sample collected with the CMS detector at the LHC. The sample corresponds to an integrated luminosity of 3.2 pb-1. Event-shape ...

  12. John von Neumann Institute for Computing Structural Patterns in Ge/Sb/Te Phase-Change

    E-Print Network [OSTI]

    of the phases involved and the nature of the phase transition in the nanoscale bits pose continuing challenges square'. The rapid amorphous- to-crystalline phase change can be viewed as a re-orientation of disorderedJohn von Neumann Institute for Computing Structural Patterns in Ge/Sb/Te Phase-Change Materials J

  13. Terahertz photoconductivity of Pb1-xSnxTe,,In... Dmitry Khokhlov,1,a

    E-Print Network [OSTI]

    Ganichev, Sergey

    of different materials, including explosives, etc.3­6 Development of detectors of la- ser radiation system-indium-doped Pb1-xSnxTe-can be implemented for detection of terahertz radiation yielding extremely- ductivity periodically quenched by short radiofrequency pulses. A remarkable feature is that this material

  14. Investigation of deep level defects in CdTe thin films

    SciTech Connect (OSTI)

    Shankar, H.; Castaldini, A.; Dauksta, E.; Medvid, A.; Cavallini, A.

    2014-02-21

    In the past few years, a large body of work has been dedicated to CdTe thin film semiconductors, as the electronic and optical properties of CdTe nanostructures make them desirable for photovoltaic applications. The performance of semiconductor devices is greatly influenced by the deep levels. Knowledge of parameters of deep levels present in as-grown materials and the identification of their origin is the key factor in the development of photovoltaic device performance. Photo Induced Current Transient Spectroscopy technique (PICTS) has proven to be a very powerful method for the study of deep levels enabling us to identify the type of traps, their activation energy and apparent capture cross section. In the present work, we report the effect of growth parameters and LASER irradiation intensity on the photo-electric and transport properties of CdTe thin films prepared by Close-Space Sublimation method using SiC electrical heating element. CdTe thin films were grown at three different source temperatures (630, 650 and 700 °C). The grown films were irradiated with Nd:YAG LASER and characterized by Photo-Induced Current Transient Spectroscopy, Photocurrent measurementand Current Voltage measurements. The defect levels are found to be significantly influenced by the growth temperature.

  15. Search for anomalous production of multilepton events in pp collisions at ?s = 7 TeV

    E-Print Network [OSTI]

    Bauer, Gerry P.

    A search for anomalous production of events with three or more isolated leptons in pp collisions at ?s = 7 TeV is presented. The data, corresponding to an integrated luminosity of 4.98 fb[superscript ?1], were collected ...

  16. Search for fractionally charged particles in pp collisions at ?s=7??TeV

    E-Print Network [OSTI]

    Apyan, Aram

    A search is presented for free heavy long-lived fractionally charged particles produced in pp collisions at ?s=7??TeV. The data sample was recorded by the CMS detector at the LHC and corresponds to an integrated luminosity ...

  17. Search for Three-Jet Resonances in pp Collisions at ?s=7??TeV

    E-Print Network [OSTI]

    Bauer, Gerry P.

    A search for three-jet hadronic resonance production in pp collisions at a center-of-mass energy of 7 TeV has been conducted by the CMS Collaboration at the LHC, using a data sample corresponding to an integrated luminosity ...

  18. Inclusive Search for Supersymmetry Using Razor Variables in pp Collisions at ?s=7??TeV

    E-Print Network [OSTI]

    Apyan, Aram

    An inclusive search is presented for new heavy particle pairs produced in ?s=7??TeV proton-proton collisions at the LHC using 4.7±0.1??fb[superscript -1] of integrated luminosity. The selected events are analyzed in the ...

  19. Religio e TeRRiTRio no BRasil: 1991/2010

    E-Print Network [OSTI]

    Díaz, Lorenzo J.

    Religião e TeRRiTóRio no BRasil: 1991/2010 Cesar Romero Jacob Dora Rodrigues Hees Philippe Waniez. Jacob, Cesar Romero Religião e território no Brasil [recurso eletrônico] : 1991/2010 / Cesar Romero.) ; 21 cm Inclui bibliografia ISBN 978-85-8006-100-0 1. Religiões - Indicadores - Brasil. 2. Indicadores

  20. First Results of a Study of TeV emission of GRBs in Milagrito

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    V energies were observed by the Burst And Transient Satellite Experiment (BATSE) aboard the Compton Gamma-Ray a search for TeV counterparts to -ray bursts. Within the Milagrito #12;eld of view 54 -ray bursts at ke coincident with each of these -ray bursts. For each burst, a circular search region was de#12;ned

  1. Surveying the TeV Sky with Milagro C.P. Lansdell for the Milagro Collaboration

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    V emitters of gamma-ray bursts, galaxy clusters, and EGRET unidentified sources. Based on the success 87545 Abstract. A wide field of view, high duty factor, TeV gamma-ray observatory is essential of Milagro, a second generation water Cherenkov gamma-ray observatory is planned which will give an increase

  2. UNIVERSITY OF CALIFORNIA Search for a TeV Component of GammaRay Bursts

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    UNIVERSITY OF CALIFORNIA IRVINE Search for a TeV Component of Gamma­Ray Bursts Using the Milagrito Acknowledgements xiii Curriculum Vitae xv Abstract xvi 1. Introduction 1 2. Gamma­Ray Bursts: Observations.2 The Compton Gamma­Ray Observatory . . . . . . . . . . . . . . . . . . . 6 2.3 BATSE's Contributions

  3. Les Houches 2011: Physics at TeV Colliders New Physics Working Group Report

    E-Print Network [OSTI]

    Brooijmans, G; Moortgat, F; Santiago, J; Skands, P; Vásquez, D Albornoz; Allanach, B C; Alloul, A; Arbey, A; Azatov, A; Baer, H; Balázs, C; Barr, A; Basso, L; Battaglia, M; Bechtle, P; Bélanger, G; Belyaev, A; Benslama, K; Bergström, L; Bharucha, A; Boehm, C; Bondarenko, M; Bondu, O; Boos, E; Boudjema, F; Bringmann, T; Brown, M; Bunichev, V; Calvet, S; Campanelli, M; Carmona, A; Cerdeño, D G; Chala, M; Chivukula, R S; Chowdhury, D; Christensen, N D; Cirelli, M; Cox, S; Cranmer, K; Da Silva, J; Delahaye, T; De Roeck, A; Djouadi, A; Dobson, E; Dolan, M; Donato, F; La Rochelle, G Drieu; Duda, G; Duhr, C; Dumont, B; Edsjö, J; Ellis, J; Evoli, C; Falkowski, A; Felcini, M; Fuks, B; Gabrielli, E; Gaggero, D; Gascon-Shotkin, S; Ghosh, D K; Giammanco, A; Godbole, R M; Gondolo, P; Goto, T; Grasso, D; Gris, P; Guadagnoli, D; Gunion, J F; Haisch, U; Hartgring, L; Heinemeyer, S; Hirsch, M; Hewett, J; Ismail, A; Jeltema, T; Kadastik, M; Kakizaki, M; Kannike, K; Khalil, S; Kneur, J-L; Krämer, M; Kraml, S; Kreiss, S; Lavalle, J; Leane, R; Lykken, J; Maccione, L; Mahmoudi, F; Mangano, M; Martin, S P; Maurin, D; Moreau, G; Moretti, S; Moskalenko, I; Moultaka, G; Muhlleitner, M; Niessen, I; O'Leary, B; Orlando, E; Panci, P; Polesello, G; Porod, W; Porter, T; Profumo, S; Prosper, H; Pukhov, A; Racioppi, A; Raidal, M; de Traubenberg, M Rausch; Renaud, A; Reuter, J; Rizzo, T G; Robens, T; Rodríguez-Marrero, A Y; Salati, P; Savage, C; Scott, P; Sekmen, S; Semenov, A; Shan, C -L; Shepherd-Themistocleous, C; Simmons, E H; Slavich, P; Speckner, C; Staub, F; Strong, A; Taillet, R; Thomas, F S; Thomas, M C; Tomalin, I; Tytgat, M; Ughetto, M; Valéry, L; Walker, D G E; Weiler, A; West, S M; White, C D; Williams, A J; Wingerter, A; Wymant, C; Yu, J -H; Yuan, C -P; Zerwas, D

    2012-01-01

    We present the activities of the "New Physics" working group for the "Physics at TeV Colliders" workshop (Les Houches, France, 30 May-17 June, 2011). Our report includes new agreements on formats for interfaces between computational tools, new tool developments, important signatures for searches at the LHC, recommendations for presentation of LHC search results, as well as additional phenomenological studies.

  4. Les Houches 2011: Physics at TeV Colliders New Physics Working Group Report

    E-Print Network [OSTI]

    G. Brooijmans; B. Gripaios; F. Moortgat; J. Santiago; P. Skands; D. Albornoz Vásquez; B. C. Allanach; A. Alloul; A. Arbey; A. Azatov; H. Baer; C. Balázs; A. Barr; L. Basso; M. Battaglia; P. Bechtle; G. Bélanger; A. Belyaev; K. Benslama; L. Bergström; A. Bharucha; C. Boehm; M. Bondarenko; O. Bondu; E. Boos; F. Boudjema; T. Bringmann; M. Brown; V. Bunichev; S. Calvet; M. Campanelli; A. Carmona; D. G. Cerdeño; M. Chala; R. S. Chivukula; D. Chowdhury; N. D. Christensen; M. Cirelli; S. Cox; K. Cranmer; J. Da Silva; T. Delahaye; A. De Roeck; A. Djouadi; E. Dobson; M. Dolan; F. Donato; G. Drieu La Rochelle; G. Duda; C. Duhr; B. Dumont; J. Edsjö; J. Ellis; C. Evoli; A. Falkowski; M. Felcini; B. Fuks; E. Gabrielli; D. Gaggero; S. Gascon-Shotkin; D. K. Ghosh; A. Giammanco; R. M. Godbole; P. Gondolo; T. Goto; D. Grasso; P. Gris; D. Guadagnoli; J. F. Gunion; U. Haisch; L. Hartgring; S. Heinemeyer; M. Hirsch; J. Hewett; A. Ismail; T. Jeltema; M. Kadastik; M. Kakizaki; K. Kannike; S. Khalil; J-L. Kneur; M. Krämer; S. Kraml; S. Kreiss; J. Lavalle; R. Leane; J. Lykken; L. Maccione; F. Mahmoudi; M. Mangano; S. P. Martin; D. Maurin; G. Moreau; S. Moretti; I. Moskalenko; G. Moultaka; M. Muhlleitner; I. Niessen; B. O'Leary; E. Orlando; P. Panci; G. Polesello; W. Porod; T. Porter; S. Profumo; H. Prosper; A. Pukhov; A. Racioppi; M. Raidal; M. Rausch de Traubenberg; A. Renaud; J. Reuter; T. G. Rizzo; T. Robens; A. Y. Rodríguez-Marrero; P. Salati; C. Savage; P. Scott; S. Sekmen; A. Semenov; C. -L. Shan; C. Shepherd-Themistocleous; E. H. Simmons; P. Slavich; C. Speckner; F. Staub; A. Strong; R. Taillet; F. S. Thomas; M. C. Thomas; I. Tomalin; M. Tytgat; M. Ughetto; L. Valéry; D. G. E. Walker; A. Weiler; S. M. West; C. D. White; A. J. Williams; A. Wingerter; C. Wymant; J. -H. Yu; C. -P. Yuan; D. Zerwas

    2012-04-20

    We present the activities of the "New Physics" working group for the "Physics at TeV Colliders" workshop (Les Houches, France, 30 May-17 June, 2011). Our report includes new agreements on formats for interfaces between computational tools, new tool developments, important signatures for searches at the LHC, recommendations for presentation of LHC search results, as well as additional phenomenological studies.

  5. Detection of TeV Gamma-Rays from extended sources with Milagro

    E-Print Network [OSTI]

    Parkinson, P M S; Atkins, R; Benbow, W; Berley, D; Blaufuss, E; Coyne, D G; De Young, T R; Dingus, B L; Dorfan, D E; Ellsworth, R W; Fleysher, L; Gisler, G; González, M M; Goodman, J A; Haines, T J; Hays, E; Hoffman, C M; Kelley, L A; Lansdell, C P; Linnemann, J T; McEnery, J E; Miller, R S; Mincer, A I; Morales, M F; Némethy, P; Noyes, D; Ryan, J M; Samuelson, F W; Saz-Parkinson, P M; Shoup, A; Sinnis, G; Smith, A J; Sullivan, G W; Williams, D A; Wilson, M E; Xu, X W; Yodh, G B

    2005-01-01

    The Milagro gamma-ray observatory employs a water Cherenkov detector to observe extensive air showers produced by high-energy particles impacting in the Earth's atmosphere. A 4800 m$^{2}$ pond instrumented with 723 8" PMTs detects Cherenkov light produced by secondary air-shower particles. An array of 175 4000 liter water tanks surrounding the central pond detector was recently added, extending the physical area of the Milagro observatory to 40,000 m$^{2}$ and substantially increasing the sensitivity of the detector. Because of its wide field of view and high duty cycle, Milagro is ideal for monitoring the northern sky almost continuously ($>$90% duty cycle) in the 100 GeV to 100 TeV energy range. Here we discuss the first detection of TeV gamma-rays from the inner Galactic plane region. We also report the detection of an extended TeV source coincident with the EGRET source 3EG J0520+2556, as well as the observation of extended TeV emission from the Cygnus region of the Galactic plane.

  6. Discovery of TeV Gamma-Ray Emission from the Cygnus Region of the Galaxy

    E-Print Network [OSTI]

    Abdo, A A; Berley, D; Blaufuss, E; Casanova, S; Chen, C; Coyne, D G; Delay, R S; Dingus, B L; Ellsworth, R W; Fleysher, L; Fleysher, R; González, M M; Goodman, J A; Hays, E; Hoffman, C M; Kolterman, B E; Kelley, L A; Lansdell, C P; Linnemann, J T; McEnery, J E; Mincer, A I; Moskalenko, I V; Némethy, P; Noyes, D; Ryan, J M; Samuelson, F W; Parkinson, P M S; Schneider, M; Shoup, A; Sinnis, G; Smith, A J; Strong, A W; Sullivan, G W; Vasileiou, V; Walker, G P; Williams, D A; Xu, X W; Yodh, G B

    2006-01-01

    The diffuse gamma radiation arising from the interaction of cosmic ray particles with matter and radiation in the Galaxy is one of the few probes available to study the origin of the cosmic rays. Milagro is a water Cherenkov detector that continuously views the entire overhead sky. The large field-of-view combined with the long observation time makes Milagro the most sensitive instrument available for the study of large, low surface brightness sources such as the diffuse gamma radiation arising from interactions of cosmic radiation with interstellar matter. In this paper we present spatial and flux measurements of TeV gamma-ray emission from the Cygnus Region. The TeV image shows at least one new source MGRO J2019+37 as well as correlations with the matter density in the region as would be expected from cosmic-ray proton interactions. However, the TeV gamma-ray flux as measured at ~12 TeV from the Cygnus region (after excluding MGRO J2019+37) exceeds that predicted from a conventional model of cosmic ray prod...

  7. Nuclear structure relevant to neutrinoless double beta decay candidate {sup 130}Te and other recent results

    SciTech Connect (OSTI)

    Kay, B. P. [Physics Division, Argonne National Laboratory, Illinois 60439 (United States)

    2013-12-30

    We have undertaken a series of single-nucleon and pair transfer reaction measurements to help constrain calculations of the nuclear matrix elements for neutrinoless double beta decay. In this talk, a short overview of measurements relevant to the {sup 130}Te?{sup 130}Xe system is given. Brief mention is made of other recent and forthcoming results.

  8. MicroTE: Fine Grained Traffic Engineering for Data Centers Theophilus Benson

    E-Print Network [OSTI]

    Akella, Aditya

    MicroTE: Fine Grained Traffic Engineering for Data Centers Theophilus Benson , Ashok Anand , Aditya center traffic characteristics on data cen- ter traffic engineering is not well understood. In particu on the network making it appro- priate for current and future data centers. Categories and Subject Descriptors C

  9. Measurement of upsilon production in 7 TeV pp collisions at ATLAS

    E-Print Network [OSTI]

    Taylor, Frank E.

    Using 1.8??fb[superscript -1] of pp collisions at a center-of-mass energy of 7 TeV recorded by the ATLAS detector at the Large Hadron Collider, we present measurements of the production cross sections of ?(1S,2S,3S) mesons. ...

  10. 14%-efficient flexible CdTe solar cells on ultra-thin glass substrates

    SciTech Connect (OSTI)

    Rance, W. L.; Burst, J. M.; Reese, M. O.; Gessert, T. A.; Metzger, W. K.; Barnes, T. M. [National Renewable Energy Laboratory, Golden, Colorado 80401 (United States); Meysing, D. M.; Wolden, C. A. [Colorado School of Mines, Golden, Colorado 80401 (United States); Garner, S.; Cimo, P. [Corning Incorporated, Corning, New York 14831 (United States)

    2014-04-07

    Flexible glass enables high-temperature, roll-to-roll processing of superstrate devices with higher photocurrents than flexible polymer foils because of its higher optical transmission. Using flexible glass in our high-temperature CdTe process, we achieved a certified record conversion efficiency of 14.05% for a flexible CdTe solar cell. Little has been reported on the flexibility of CdTe devices, so we investigated the effects of three different static bending conditions on device performance. We observed a consistent trend of increased short-circuit current and fill factor, whereas the open-circuit voltage consistently dropped. The quantum efficiency under the same static bend condition showed no change in the response. After storage in a flexed state for 24 h, there was very little change in device efficiency relative to its unflexed state. This indicates that flexible glass is a suitable replacement for rigid glass substrates, and that CdTe solar cells can tolerate bending without a decrease in device performance.

  11. Synthesis, characterization and performance of Cd1xInxTe compound for solar cell applications

    E-Print Network [OSTI]

    Chow, Lee

    devices, solar energy converters, Videocon devices, sensors, medi- cal imaging and nanodevices [1­11]. CdSynthesis, characterization and performance of Cd1ÀxInxTe compound for solar cell applications Atef), Tebbin, P.O. Box 87 Helwan, Cairo 11412, Egypt b Department of Physics, University of Central Florida

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

    SciTech Connect (OSTI)

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

    2011-07-01

    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.

  13. High thermoelectric performance by resonant dopant indium in nanostructured SnTe

    E-Print Network [OSTI]

    Liao, Bolin

    From an environmental perspective, lead-free SnTe would be preferable for solid-state waste heat recovery if its thermoelectric figure-of-merit could be brought close to that of the lead-containing chalcogenides. In this ...

  14. HESS J1640-465 - an exceptionally luminous TeV gamma-ray SNR

    E-Print Network [OSTI]

    Abramowski, A; Benkhali, F Ait; Akhperjanian, A G; Angüner, E; Anton, G; Balenderan, S; Balzer, A; Barnacka, A; Becherini, Y; Tjus, J Becker; Bernlöhr, K; Birsin, E; Bissaldi, E; Biteau, J; Böttcher, M; Boisson, C; Bolmont, J; Bordas, P; Brucker, J; Brun, F; Brun, P; Bulik, T; Carrigan, S; Casanova, S; Cerruti, M; Chadwick, P M; Chalme-Calvet, R; Chaves, R C G; Cheesebrough, A; Chrétien, M; Colafrancesco, S; Cologna, G; Conrad, J; Couturier, C; Cui, Y; Dalton, M; Daniel, M K; Davids, I D; Degrange, B; Deil, C; deWilt, P; Dickinson, H J; Djannati-Ataï, A; Domainko, W; Drury, L O'C; Dubus, G; Dutson, K; Dyks, J; Dyrda, M; Edwards, T; Egberts, K; Eger, P; Espigat, P; Farnier, C; Fegan, S; Feinstein, F; Fernandes, M V; Fernandez, D; Fiasson, A; Fontaine, G; Förster, A; Füßling, M; Gajdus, M; Gallant, Y A; Garrigoux, T; Giavitto, G; Giebels, B; Glicenstein, J F; Grondin, M -H; Grudzi?ska, M; Häffner, S; Hahn, J; Harris, J; Heinzelmann, G; Henri, G; Hermann, G; Hervet, O; Hillert, A; Hinton, J A; Hofmann, W; Hofverberg, P; Holler, M; Horns, D; Jacholkowska, A; Jahn, C; Jamrozy, M; Janiak, M; Jankowsky, F; Jung, I; Kastendieck, M A; Katarzy?ski, K; Katz, U; Kaufmann, S; Khélifi, B; Kieffer, M; Klepser, S; Klochkov, D; Klu?niak, W; Kneiske, T; Kolitzus, D; Komin, Nu; Kosack, K; Krakau, S; Krayzel, F; Krüger, P P; Laffon, H; Lamanna, G; Lefaucheur, J; Lemière, A; Lemoine-Goumard, M; Lenain, J -P; Lennarz, D; Lohse, T; Lopatin, A; Lu, C -C; Marandon, V; Marcowith, A; Marx, R; Maurin, G; Maxted, N; Mayer, M; McComb, T J L; Méhault, J; Meintjes, P J; Menzler, U; Meyer, M; Moderski, R; Mohamed, M; Moulin, E; Murach, T; Naumann, C L; de Naurois, M; Niemiec, J; Nolan, S J; Oakes, L; Ohm, S; Wilhelmi, E de Oña; Opitz, B; Ostrowski, M; Oya, I; Panter, M; Parsons, R D; Arribas, M Paz; Pekeur, N W; Pelletier, G; Perez, J; Petrucci, P -O; Peyaud, B; Pita, S; Poon, H; Pühlhofer, G; Punch, M; Quirrenbach, A; Raab, S; Raue, M; Reimer, A; Reimer, O; Renaud, M; Reyes, R de los; Rieger, F; Rob, L; Romoli, C; Rosier-Lees, S; Rowell, G; Rudak, B; Rulten, C B; Sahakian, V; Sanchez, D A; Santangelo, A; Schlickeiser, R; Schüssler, F; Schulz, A; Schwanke, U; Schwarzburg, S; Schwemmer, S; Sol, H; Spengler, G; Spies, F; Stawarz, ?; Steenkamp, R; Stegmann, C; Stinzing, F; Stycz, K; Sushch, I; Szostek, A; Tavernet, J -P; Tavernier, T; Taylor, A M; Terrier, R; Tluczykont, M; Trichard, C; Valerius, K; van Eldik, C; van Soelen, B; Vasileiadis, G; Venter, C; Viana, A; Vincent, P; Vink, J; Völk, H J; Volpe, F; Vorster, M; Vuillaume, T; Wagner, S J; Wagner, P; Ward, M; Weidinger, M; Weitzel, Q; White, R; Wierzcholska, A; Willmann, P; Wörnlein, A; Wouters, D; Zabalza, V; Zacharias, M; Zajczyk, A; Zdziarski, A A; Zech, A; Zechlin, H -S

    2014-01-01

    The results of follow-up observations of the TeV gamma-ray source HESSJ 1640-465 from 2004 to 2011 with the High Energy Stereoscopic System (H.E.S.S.) are reported in this work. The spectrum is well described by an exponential cut-off power law with photon index Gamma=2.11 +/- 0.09_stat +/- 0.10_sys, and a cut-off energy of E_c = (6.0 +2.0 -1.2) TeV. The TeV emission is significantly extended and overlaps with the north-western part of the shell of the SNR G338.3-0.0. The new H.E.S.S. results, a re-analysis of archival XMM-Newton data, and multi-wavelength observations suggest that a significant part of the gamma-ray emission from HESS J1640-465 originates in the SNR shell. In a hadronic scenario, as suggested by the smooth connection of the GeV and TeV spectra, the product of total proton energy and mean target density could be as high as W_p n_H ~ 4 x 10^52 (d/10kpc)^2 erg cm^-3.

  15. Very Strong TeV Emission as Gamma-Ray Burst Afterglows

    E-Print Network [OSTI]

    Tomonori Totani

    1998-05-20

    Gamma-ray bursts (GRBs) and following afterglows are considered to be produced by dissipation of kinetic energy of a relativistic fireball and radiation process is widely believed as synchrotron radiation or inverse Compton scattering of electrons. We argue that the transfer of kinetic energy of ejecta into electrons may be inefficient process and hence the total energy released by a GRB event is much larger than that emitted in soft gamma-rays, by a factor of \\sim (m_p/m_e). We show that, in this case, very strong emission of TeV gamma-rays is possible due to synchrotron radiation of protons accelerated up to \\sim 10^{21} eV, which are trapped in the magnetic field of afterglow shock and radiate their energy on an observational time scale of \\sim day. This suggests a possibility that GRBs are most energetic in TeV range and such TeV gamma-rays may be detectable from GRBs even at cosmological distances, i.e., z \\sim 1, by currently working ground-based telescopes. Furthermore, this model gives a quantitative explanation for the famous long-duration GeV photons detected from GRB940217. If TeV gamma-ray emission which is much more energetic than GRB photons is detected, it provides a strong evidence for acceleration of protons up to \\sim 10^{21} eV.

  16. Observation of Exclusive ?? Production in pp? Collisions at ?s=1.96??TeV

    E-Print Network [OSTI]

    Gomez-Ceballos, Guillelmo

    We have observed exclusive ?? production in proton-antiproton collisions at ?s=1.96??TeV, using data from 1.11±0.07??fb[superscript -1] integrated luminosity taken by the Run II Collider Detector at Fermilab. We selected ...

  17. Results on CP Violation from Belle T.E. Browder representing the Belle Collaboration

    E-Print Network [OSTI]

    Browder, Tom

    Results on CP Violation from Belle T.E. Browder representing the Belle Collaboration Department of Physics, University of Hawaii, Honolulu, Hawaii Abstract. I describe the recent measurement of the CP In 1973, Kobayashi and Maskawa (KM) first proposed a model where CP violation is incorporated

  18. Left-Right Gauge Symmetry at the TeV Energy Scale

    E-Print Network [OSTI]

    Ernest Ma

    1994-11-28

    Two first examples beyond the standard model are given which exhibit left-right symmetry (g_L = g_R) and supersymmetry at a few TeV, together with gauge-coupling unification at around 10^{16} GeV.

  19. Pre-Approved Technical Elective (TE) Course Options for Bioengineering: Biotechnology Program

    E-Print Network [OSTI]

    Gleeson, Joseph G.

    Pre-Approved Technical Elective (TE) Course Options for Bioengineering: Biotechnology Program are "BENG" courses not required for the Bioengineering: Biotechnology major and other 4-unit, upper ­ Biomechanics I and II BENG 140AB* ­ Bioengineering Physiology I and II (BTEC students are advised not to take

  20. PRE-APPROVED TECHNICAL ELECTIVE (TE) COURSE OPTIONS FOR THE BIOENGINEERING PROGRAM

    E-Print Network [OSTI]

    Gleeson, Joseph G.

    PRE-APPROVED TECHNICAL ELECTIVE (TE) COURSE OPTIONS FOR THE BIOENGINEERING PROGRAM The Technical" courses not required for the Bioengineering major and other 4-unit, upper-division (100 series) courses requirements in any majors in the Department of Bioengineering. #12;

  1. 62-TeV center of mass hadron collider with superbunch beams

    SciTech Connect (OSTI)

    Ryuji Yamada et al.

    2001-11-05

    The scheme of a 62-TeV center of mass p-p collider with superbunch beams at Fermilab is proposed as a practical and realistically achievable future project. It will be built in two stages, using the same tunnel, first with a 2 Tesla low field magnet collider ring and later with a 10 Tesla high field magnet collider ring. Both low and high field magnets have twin bore aperture and will be installed in the tunnel with the circumference of 87.25 km. In each bore a proton beam is accelerated, using induction cavities to increase luminosity. In the first stage they install a 7 TeV accelerator ring with operating field of 2 Tesla, based on the superferric transmission-line design. This ring will be operated at a 14-TeV center of mass collider. This will have the same energy as the LHC, but it will have 15 times higher luminosity, namely 1.5 x 10{sup 35}/cm{sup 2}/sec. The estimated synchrotron radiation is negligible with this machine. The existing Fermilab accelerator system, including the 150 GeV main injector, will be used as the injector system. Its rough cost estimation and schedule for this first stage are presented. In the second stage proton beams are accelerated, also using induction cavities up to 31 TeV with the 10 Tesla dipole magnets. The counter circulating beams will collide with the 62-TeV center of mass energy. With the superbunch beams they can expect the luminosity can be increased about 15 times more than the conventional method with RF cavities. It will be 10{sup 35}/cm{sup 2}/sec. In the second stage, the synchrotron radiation power will be about 12 W/m, and they need an elaborated beam screen.

  2. Novel Approaches to Wide Bandgap CuInSe2 Based Absorbers

    SciTech Connect (OSTI)

    William N. Shafarman

    2011-04-28

    This project targeted the development of high performance wide bandgap solar cells based on thin film alloys of CuInSe2 to relax constraints on module design and enable tandem solar cell structures. This addressed goals of the Solar Energy Technologies Program for Next Generation PV to develop technology needed for higher thin film module efficiency as a means to reduce costs. Specific objectives of the research project were: 1) to develop the processes and materials required to improve the performance of wide bandgap thin film solar cells based on alloys of CuInSe2, and 2) to provide the fundamental science and engineering basis for the material, electronic, and device properties required to effectively apply these processes and materials to commercial manufacture. CuInSe2-based photovoltaics have established the highest efficiencies of the thin film materials at both the cell and module scales and are actively being scaled up to commercialization. In the highest efficiency cells and modules, the optical bandgap, a function of the CuInSe2-based alloy composition, is relatively low compared to the optimum match to the solar spectrum. Wider bandgap alloys of CuInSe2 produce higher cell voltages which can improve module performance and enable the development of tandem solar cells to boost the overall efficiency. A focus for the project was alloying with silver to form (AgCu)(InGa)Se2 pentenary thin films deposited by elemental co-evaporation which gives the broadest range of control of composition and material properties. This alloy has a lower melting temperature than Ag-free, Cu-based chalcopyrite compounds, which may enable films to be formed with lower defect densities and the (AgCu)(InGa)Se2 films give improved material properties and better device performance with increasing bandgap. A comprehensive characterization of optical, structural, and electronic properties of (AgCu)(InGa)Se2 was completed over the complete compositional range 0 ? Ga/(In+Ga) ? 1 and 0 ? Ag/(Ag+Cu) ? 1. Evidence of improved material quality includes reduced sub-bandgap optical absorption, sharper bandtails, and increased grain size with Ag addition. The Ag alloying was shown to increase the range of bandgaps over which solar cells can be fabricated without any drop-off in performance. With bandgap greater than 1.6 eV, in the range needed for tandem solar cells, (AgCu)(InGa)Se2 gave higher efficiency than other CuInSe2-based alloys. Using a simple single-stage co-evaporation process, a solar cell with 17.6% efficiency using a film with bandgap = 1.3 eV was achieved, demonstrating the viability of (AgCu)(InGa)Se2 for high efficiency devices. With a three-stage co-evaporation process for (AgCu)(InGa)Se2 deposition a device with efficiency = 13.0 % and VOC = 890 mV with JSC = 20.5 mA/cm2, FF = 71.3% was achieved. This surpasses the performance of other wide bandgap CuInSe2-based solar cells. Detailed characterization of the electronic properties of the materials and devices including the application of advanced admittance-based easements was completed.

  3. Impact of annealing on the chemical structure and morphology of the thin-film CdTe/ZnO interface

    SciTech Connect (OSTI)

    Horsley, K. Hanks, D. A.; Weir, M. G.; Beal, R. J.; Wilks, R. G.; Blum, M.; Häming, M.; Hofmann, T.; Weinhardt, L.; and others

    2014-07-14

    To enable an understanding and optimization of the optoelectronic behavior of CdTe-ZnO nanocomposites, the morphological and chemical properties of annealed CdTe/ZnO interface structures were studied. For that purpose, CdTe layers of varying thickness (4–24?nm) were sputter-deposited on 100?nm-thick ZnO films on surface-oxidized Si(100) substrates. The morphological and chemical effects of annealing at 525?°C were investigated using X-ray Photoelectron Spectroscopy (XPS), X-ray-excited Auger electron spectroscopy, energy dispersive X-ray spectroscopy, scanning electron microscopy, and atomic force microscopy. We find a decrease of the Cd and Te surface concentration after annealing, parallel to an increase in Zn and O signals. While the as-deposited film surfaces show small grains (100?nm diameter) of CdTe on the ZnO surface, annealing induces a significant growth of these grains and separation into islands (with diameters as large as 1??m). The compositional change at the surface is more pronounced for Cd than for Te, as evidenced using component peak fitting of the Cd and Te 3d XPS peaks. The modified Auger parameters of Cd and Te are also calculated to further elucidate the local chemical environment before and after annealing. Together, these results suggest the formation of tellurium and cadmium oxide species at the CdTe/ZnO interface upon annealing, which can create a barrier for charge carrier transport, and might allow for a deliberate modification of interface properties with suitably chosen thermal treatment parameters.

  4. Electronic structure, irreversibility line and magnetoresistance of Cu0.3Bi2Se3 superconductor

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hemian, Yi; Gu, Genda; Chen, Chao -Yu; Sun, Xuan; Xie, Zhuo -Jin; Feng, Ya; Liang, Ai -Ji; Peng, Ying -Ying; He, Shao -Long; Zhao, Lin; et al

    2015-06-01

    CuxBi2Se3 is a superconductor that is a potential candidate for topological superconductors. We report our laser-based angle-resolved photoemission measurement on the electronic structure of the CuxBi2Se3 superconductor, and a detailed magneto-resistance measurement in both normal and superconducting states. We find that the topological surface state of the pristine Bi2Se3 topological insulator remains robust after the Cu-intercalation, while the Dirac cone location moves downward due to electron doping. Detailed measurements on the magnetic field-dependence of the resistance in the superconducting state establishes an irreversibility line and gives a value of the upper critical field at zero temperature of ~4000 Oe formore »the Cu0.3Bi2Se3 superconductor with a middle point Tc of 1.9K. The relation between the upper critical field Hc2 and temperature T is different from the usual scaling relation found in cuprates and in other kinds of superconductors. Small positive magneto-resistance is observed in Cu0.3Bi2Se3 superconductors up to room temperature. As a result, these observations provide useful information for further study of this possible candidate for topological superconductors.« less

  5. In-situ surface composition measurements of CuGaSe{sub 2} thin films

    SciTech Connect (OSTI)

    Fons, P.; Yamada, A.; Niki, S.; Oyanagi, H.

    1998-12-31

    Two CuGaSe{sub 2} films were grown by molecular beam epitaxy onto GaAs (001) substrates with varying Cu/Ga flux ratios under Se overpressure conditions. Growth was interrupted at predetermined times and the surface composition was measured using Auger electron spectroscopy after which growth was continued. After growth, the film composition was analyzed using voltage dependent electron microprobe spectroscopy. Film structure and morphology were also analyzed using x-ray diffraction and atomic force microscopy. The film with a Cu/Ga ratio larger than unity showed evidence of surface segregation of a second Cu-rich phase with a Cu/Se composition ratio slightly greater than unity. A second CuGaSe{sub 2} film with a Cu/Ga ratio of less than unity showed no change in surface composition with time and was also consistent with bulk composition measurements. Diffraction measurements indicated a high concentration of twins as well as the presence of domains with mixed c and a axes in the Ga-rich film. The Cu-rich films by contrast were single domain and had a narrower mosaics. High sensitivity scans along the [001] reciprocal axis did not exhibit any new peaks not attributable to either the substrate or the CuGaSe{sub 2} thin film.

  6. Search for contact interactions in dimuon events from pp collisions at ?s=7 TeV with the ATLAS detector

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Aad, G.; Abbott, B.; Abdallah, J.; Abdelalim, A. A.; Abdesselam, A.; Abdinov, O.; Abi, B.; Abolins, M.; Abramowicz, H.; Abreu, H.; et al

    2011-07-01

    A search for contact interactions has been performed using dimuon events recorded with the ATLAS detector in proton-proton collisions at ?s=7 TeV. The data sample corresponds to an integrated luminosity of 42 pb?¹. No significant deviation from the standard model is observed in the dimuon mass spectrum, allowing the following 95% C.L. limits to be set on the energy scale of contact interactions: ?>4.9 TeV (4.5 TeV) for constructive (destructive) interference in the left-left isoscalar compositeness model. These limits are the most stringent to date for ??qq contact interactions.

  7. A Novel and Functional Single Layer Sheet of ZnSe

    SciTech Connect (OSTI)

    Zhou, Jia [ORNL; Sumpter, Bobby G [ORNL; Kent, Paul R [ORNL; Huang, Jingsong [ORNL

    2015-01-01

    In this Communication, we report a novel singlelayer sheet of ZnSe, with a three-atomic thickness, which demonstrates a strong quantum confinement effect by exhibiting a large blue shift of 2.0 eV in its absorption edge relative to the zinc blende (ZB) bulk phase. Theoretical optical absorbance shows that the largest absorption of this ultrathin single-layer sheet of ZnSe occurs at a wavelength similar to its four-atom-thick doublelayer counterpart but with higher photoabsorption efficiency, suggesting a superior behavior on incident photon-to-current conversion efficiency for solar water splitting, among other potential applications. The results presented herein for ZnSe may be generalized to other group II-VI analogues.

  8. Charge-transfer dynamics in multilayered PbS and PbSe quantum dot architectures

    SciTech Connect (OSTI)

    Xu, F.; Ma, X.; Haughn, C. R.; Doty, M. F.; Cloutier, S. G.

    2014-02-03

    We demonstrate control of the charge transfer process in PbS and PbSe quantum dot assemblies. We first demonstrate efficient charge transfer from donor quantum dots to acceptor quantum dots in a multi-layer PbSe cascade structure. Then, we assemble type-I and type-II heterostructures using both PbS and PbSe quantum dots via careful control of the band alignment. In type-I structures, photo-generated carriers are transferred and localized in the smaller bandgap (acceptor) quantum dots, resulting in a significant luminescence enhancement. In contrast, a significant luminescence quenching and shorter emission lifetime confirms an efficient separation of photo-generated carriers in the type-II architecture.

  9. Substrate induced modulation of electronic, magnetic and chemical properties of MoSe{sub 2} monolayer

    SciTech Connect (OSTI)

    Wasey, A. H. M. Abdul; Chakrabarty, Soubhik; Das, G. P., E-mail: msgpd@iacs.res.in [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032 (India)

    2014-04-15

    Monolayer of MoSe{sub 2}, having a typical direct band gap of ?1.5 eV, is a promising material for optoelectronic and solar cell applications. When this 2D semiconductor is supported on transition metal substrates, such as Ni(111) and Cu(111), its electronic structure gets modulated. First principles density functional investigation shows the appearance of de-localized mid-gap states in the density of states. The work function of the semiconductor overlayer gets modified considerably, indicating n-type doping caused by the metal contacts. The charge transfer across the metal-semiconductor junction also significantly enhances the chemical reactivity of the MoSe{sub 2} overlayer, as observed by Hydrogen absorption. Furthermore, for Ni contact, there is a signature of induced magnetism in MoSe{sub 2} monolayer.

  10. Luminescence of CdSe/ZnS quantum dots infiltrated into an opal matrix

    SciTech Connect (OSTI)

    Gruzintsev, A. N. Emelchenko, G. A.; Masalov, V. M.; Yakimov, E. E.; Barthou, C.; Maitre, A.

    2009-02-15

    The effect of the photonic band gap in the photonic crystal, the synthesized SiO{sub 2} opal with embedded CdSe/ZnS quantum dots, on its luminescence in the visible spectral region is studied. It is shown that the position of the photonic band gap in the luminescence and reflectance spectra for the infiltrated opal depends on the diameter of the constituent nanospheres and on the angle of recording the signal. The optimal conditions for embedding the CdSe/ZnS quantum dots from the solution into the opal matrix are determined. It is found that, for the opal-CdSe/ZnS nanocomposites, the emission intensity decreases and the luminescence decay time increases in the spatial directions, in which the spectral positions of the photonic band gap and the luminescence peak of the quantum dots coincide.

  11. Ordering mechanism of stacked CdSe/ZnS{sub x}Se{sub 1-x} quantum dots: A combined reciprocal-space and real-space approach

    SciTech Connect (OSTI)

    Schmidt, Th.; Roventa, E.; Clausen, T.; Flege, J. I.; Alexe, G.; Rosenauer, A.; Hommel, D.; Falta, J.; Bernstorff, S.; Kuebel, C.

    2005-11-15

    The vertical and lateral ordering of stacked CdSe quantum dot layers embedded in ZnS{sub x}Se{sub 1-x} has been investigated by means of grazing incidence small angle x-ray scattering and transmission electron microscopy. Different growth parameters have been varied in order to elucidate the mechanisms leading to quantum dot correlation. From the results obtained for different numbers of quantum dot layers, we conclude on a self-organized process which leads to increasing ordering for progressive stacking. The dependence on the spacer layer thickness indicates that strain induced by lattice mismatch drives the ordering process, which starts to break down for too thick spacer layers in a thickness range from 45 to 80 A. Typical quantum dot distances in a range from about 110 to 160 A have been found. A pronounced anisotropy of the quantum dot correlation has been observed, with the strongest ordering along the [110] direction. Since an increased ordering is found with increasing growth temperature, the formation of stacking faults as an additional mechanism for quantum dot alignment can be ruled out.

  12. Two-step growth of two-dimensional WSe2/MoSe2 heterostructures

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gong, Yongji; Lei, Sidong; Lou, Jun; Liu, Zheng; Vajtai, Robert; Zhou, Wu; Ajayan, Pullikel M.

    2015-08-03

    Two dimensional (2D) materials have attracted great attention due to their unique properties and atomic thickness. Although various 2D materials have been successfully synthesized with different optical and electrical properties, a strategy for fabricating 2D heterostructures must be developed in order to construct more complicated devices for practical applications. Here we demonstrate for the first time a two-step chemical vapor deposition (CVD) method for growing transition-metal dichalcogenide (TMD) heterostructures, where MoSe2 was synthesized first and followed by an epitaxial growth of WSe2 on the edge and on the top surface of MoSe2. Compared to previously reported one-step growth methods, thismore »two-step growth has the capability of spatial and size control of each 2D component, leading to much larger (up to 169 ?m) heterostructure size, and cross-contamination can be effectively minimized. Furthermore, this two-step growth produces well-defined 2H and 3R stacking in the WSe2/MoSe2 bilayer regions and much sharper in-plane interfaces than the previously reported MoSe2/WSe2 heterojunctions obtained from one-step growth methods. The resultant heterostructures with WSe2/MoSe2 bilayer and the exposed MoSe2 monolayer display rectification characteristics of a p-n junction, as revealed by optoelectronic tests, and an internal quantum efficiency of 91% when functioning as a photodetector. As a result, a photovoltaic effect without any external gates was observed, showing incident photon to converted electron (IPCE) efficiencies of approximately 0.12%, providing application potential in electronics and energy harvesting.« less

  13. Ann bay lodyans 13 / Se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01

    , li pa kite anyen deye. Mouche ale ak ni jwet zo li, ni kat li, ni boutey tafya, menm ti bout tanbou a li pa bliye mete. Konsa, kon mouche rive anwo a, li tabli yon jwet zo ak yon jwet kat, ansanm ak yon konmes kleren. Sa fe, pyes travay pa ka fet... sa a se yon danje piblik. Fok yo jwenn bout li. Depi Telisfo vini an, lanfe a vin tounen yon peyi pleziyis. Abitan yo pwofite fe parese. Men tou, Telisfo pa kite yo gen anyen, menm bout sigaret pa ka rete. Sa ki pi red, se chak jou yon moun...

  14. Ann bay lodyans 1 / se Bryant Freeman ("Tonton Liben") ki pare ti liv sa a

    E-Print Network [OSTI]

    Freeman, Bryant C.

    2000-01-01

    KU ScholarWorks | http://kuscholarworks.ku.edu Ann Bay Lodyans 1 se Bryant Freeman (“Tonton Liben”) ki pare ti liv sa a 2000 by Bryant C. Freeman, ed. This work has been made available by the University of Kansas Libraries’ Office of Scholarly... Freeman (“Tonton Liben”) ki pare ti liv sa a. [Lawrence, Kan.] : Institute of Haitian Studies ; [Port-au-Prince] : Bon Nouvèl : Fondasyon Alfa Lwès, 2000. Terms of Use: http://www2.ku.edu/~scholar/docs/license.shtml ANN BAY LODYANS 1 Se Bryant Freeman...

  15. Pair correlations in nuclei involved in neutrinoless double beta decay: 76Ge and 76Se

    E-Print Network [OSTI]

    S. J. Freeman; J. P. Schiffer; A. C. C. Villari; J. A. Clark; C. Deibel; S. Gros; A. Heinz; D. Hirata; C. L. Jiang; B. P. Kay; A. Parikh; P. D. Parker; J. Qian; K. E. Rehm; X. D. Tang; V. Werner; C. Wrede

    2007-03-23

    Precision measurements were carried out to test the similarities between the ground states of 76Ge and 76Se. The extent to which these two nuclei can be characterized as consisting of correlated pairs of neutrons in a BCS-like ground state was studied. The pair removal (p,t) reaction was measured at the far forward angle of 3 degrees. The relative cross sections are consistent (at the 5% level) with the description of these nuclei in terms of a correlated pairing state outside the N=28 closed shells with no pairing vibrations. Data were also obtained for 74Ge and 78Se.

  16. Using RefWorks with BibTeX in LaTeX CREATE BiBTeX OUTPUT FOR USE WITH L

    E-Print Network [OSTI]

    MacMillan, Andrew

    ://cosmology.princeton.edu/cosmology/computing/PrincetonThesis.cls ~~~~~~~~~~~~~~~~~~~~~~~~ Additionally, A GOOGLE search on terms, LaTeX thesis style files will display many templates and style file a bibliography) To link filename.bib to your LA TEX document, you need to enter two commands: \\bibliographystyle search example: Stanford University latex thesis style file (suthesis-2e.sty) may be found @ URL: http

  17. Method of fabricating high-efficiency Cu(In,Ga)(SeS).sub.2 thin films for solar cells

    DOE Patents [OSTI]

    Noufi, Rommel (Golden, CO); Gabor, Andrew M. (Boulder, CO); Tuttle, John R. (Denver, CO); Tennant, Andrew L. (Denver, CO); Contreras, Miguel A. (Golden, CO); Albin, David S. (Denver, CO); Carapella, Jeffrey J. (Evergreen, CO)

    1995-01-01

    A process for producing a slightly Cu-poor thin film of Cu(In,Ga)(Se,S).sub.2 comprises depositing a first layer of (In,Ga).sub.x (Se,S).sub.y followed by depositing just enough Cu+(Se,S) or Cu.sub.x (Se,S) to produce the desired slightly Cu-poor material. In a variation, most, but not all, (about 90 to 99%) of the (In,Ga).sub.x (Se,S).sub.y is deposited first, followed by deposition of all the Cu+(Se,S) or Cu.sub.x (Se,S) to go near stoichiometric, possibly or even preferably slightly Cu-rich, and then in turn followed by deposition of the remainder (about 1 to 10%) of the (In,Ga).sub.x (Se,S).sub.y to end with a slightly Cu-poor composition. In yet another variation, a small portion (about 1 to 10%) of the (In,Ga).sub.x (Se,S).sub.y is first deposited as a seed layer, followed by deposition of all of the Cu+(Se,S) or Cu.sub.x (Se,S) to make a very Cu-rich mixture, and then followed deposition of the remainder of the (In,Ga).sub.x (Se,S).sub.y to go slightly Cu-poor in the final Cu(In,Ga)(Se,S).sub.2 thin film.

  18. Method of fabricating high-efficiency Cu(In,Ga)(Se,S){sub 2} thin films for solar cells

    DOE Patents [OSTI]

    Noufi, R.; Gabor, A.M.; Tuttle, J.R.; Tennant, A.L.; Contreras, M.A.; Albin, D.S.; Carapella, J.J.

    1995-08-15

    A process for producing a slightly Cu-poor thin film of Cu(In,Ga)(Se,S){sub 2} comprises depositing a first layer of (In,Ga){sub x} (Se,S){sub y} followed by depositing just enough Cu+(Se,S) or Cu{sub x} (Se,S) to produce the desired slightly Cu-poor material. In a variation, most, but not all, (about 90 to 99%) of the (In,Ga){sub x} (Se,S){sub y} is deposited first, followed by deposition of all the Cu+(Se,S) or Cu{sub x} (Se,S) to go near stoichiometric, possibly or even preferably slightly Cu-rich, and then in turn followed by deposition of the remainder (about 1 to 10%) of the (In,Ga){sub x} (Se,S){sub y} to end with a slightly Cu-poor composition. In yet another variation, a small portion (about 1 to 10%) of the (In,Ga){sub x} (Se,S){sub y} is first deposited as a seed layer, followed by deposition of all of the Cu+(Se,S) or Cu{sub x} (Se,S) to make a very Cu-rich mixture, and then followed deposition of the remainder of the (In,Ga){sub x} (Se,S){sub y} to go slightly Cu-poor in the final Cu(In,Ga)(Se,S){sub 2} thin film. 5 figs.

  19. Search for high mass dilepton resonances in pp collisions at ?s = 7 TeV with the ATLAS experiment

    E-Print Network [OSTI]

    Taylor, Frank E.

    This Letter presents a search for high mass e[superscript +]e[superscript ?] or ?[superscript +]?[superscript ?] resonances in pp collisions at ?s = 7 TeV at the LHC. The data were recorded by the ATLAS experiment during ...

  20. The effects of deep level traps on the electrical properties of semi-insulating CdZnTe

    SciTech Connect (OSTI)

    Zha, Gangqiang; Yang, Jian; Xu, Lingyan; Feng, Tao; Wang, Ning; Jie, Wanqi

    2014-01-28

    Deep level traps have considerable effects on the electrical properties and radiation detection performance of high resistivity CdZnTe. A deep-trap model for high resistivity CdZnTe was proposed in this paper. The high resistivity mechanism and the electrical properties were analyzed based on this model. High resistivity CdZnTe with high trap ionization energy E{sub t} can withstand high bias voltages. The leakage current is dependent on both the deep traps and the shallow impurities. The performance of a CdZnTe radiation detector will deteriorate at low temperatures, and the way in which sub-bandgap light excitation could improve the low temperature performance can be explained using the deep trap model.

  1. Search for excited leptons in proton-proton collisions at ?s=7??TeV with the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    The ATLAS detector is used to search for excited leptons in the electromagnetic radiative decay channel ?*???. Results are presented based on the analysis of pp collisions at a center-of-mass energy of 7 TeV corresponding ...

  2. Search for contact interactions in dilepton events from pp collisions at ?s = 7 TeV with the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    This Letter presents a search for contact interactions in the dielectron and dimuon channels using data from proton–proton collisions produced by the LHC at ?s = 7 TeV and recorded by the ATLAS detector. The data sample, ...

  3. Combined results of searches for the standard model Higgs boson in pp collisions at ?s = 7 TeV

    E-Print Network [OSTI]

    Alver, B.

    Combined results are reported from searches for the standard model Higgs boson in proton–proton collisions at ?s = 7 TeV in five Higgs boson decay modes: ??, bb, ?? , WW, and ZZ. The explored Higgs boson mass range is ...

  4. Polarization of Bi{sub 2}Te{sub 3} thin film in a floating-gate capacitor structure

    SciTech Connect (OSTI)

    Yuan, Hui E-mail: qli6@gmu.edu; Li, Haitao; Zhu, Hao; Zhang, Kai; Baumgart, Helmut; Bonevich, John E.; Richter, Curt A.; Li, Qiliang E-mail: qli6@gmu.edu

    2014-12-08

    Metal-Oxide-Semiconductor (MOS) capacitors with Bi{sub 2}Te{sub 3} thin film sandwiched and embedded inside the oxide layer have been fabricated and studied. The capacitors exhibit ferroelectric-like hysteresis which is a result of the robust, reversible polarization of the Bi{sub 2}Te{sub 3} thin film while the gate voltage sweeps. The temperature-dependent capacitance measurement indicates that the activation energy is about 0.33?eV for separating the electron and hole pairs in the bulk of Bi{sub 2}Te{sub 3}, and driving them to either the top or bottom surface of the thin film. Because of the fast polarization speed, potentially excellent endurance, and the complementary metal–oxide–semiconductor compatibility, the Bi{sub 2}Te{sub 3} embedded MOS structures are very interesting for memory application.

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

    SciTech Connect (OSTI)

    Teeter, G.; Asher, S.

    2008-05-01

    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.

  6. First Search for Multijet Resonances in root s=1.96 TeV p(p)over-bar Collisions

    E-Print Network [OSTI]

    Bauer, Gerry P.

    We present the first model independent search for three-jet hadronic resonances within multijet events in ?s=1.96??TeV pp? collisions at the Fermilab Tevatron using the CDF II detector. Pair production of supersymmetric ...

  7. Measurement of ZZ Production in Leptonic Final States at ?s of 1.96 TeV at CDF

    E-Print Network [OSTI]

    Gomez-Ceballos, Guillelmo

    In this Letter, we present a precise measurement of the total ZZ production cross section in pp? collisions at ?s=1.96??TeV, using data collected with the CDF II detector corresponding to an integrated luminosity of ...

  8. Making the Best Use of What you Have Asia Intellectual Capital Alliances a te ectua Cap ta a ce

    E-Print Network [OSTI]

    BYOBBYOB ­ Making the Best Use of What you Have Asia Intellectual Capital Alliances a te ectua Cap ta a ce 24 October 2011 Copyright © 2011 Asia Intellectual Capital Alliance. All rights reserved. #12

  9. Dijet Azimuthal Decorrelations in pp Collisions at ?s=7? [square root of s=7]?TeV

    E-Print Network [OSTI]

    Alver, Burak Han

    Measurements of dijet azimuthal decorrelations in pp collisions at ?s=7??[square root of s=7] TeV using the CMS detector at the CERN LHC are presented. The analysis is based on an inclusive dijet event sample corresponding ...

  10. Search for narrow resonances using the dijet mass spectrum in pp collisions at ?s=8??TeV

    E-Print Network [OSTI]

    Apyan, Aram

    Results are presented of a search for the production of new particles decaying to pairs of partons (quarks, antiquarks, or gluons), in the dijet mass spectrum in proton-proton collisions at ?s=8??TeV. The data sample ...

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

    E-Print Network [OSTI]

    Taylor, Frank E.

    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 ...

  12. Revealing Charge Density Wave Formation in the LaTe2 System by Angle Resolved Photoemission Spectroscopy

    E-Print Network [OSTI]

    2006-01-01

    energy electron di?raction (LEED). CDW formation is driven1D CDW materials. ARPES and LEED data were taken on LaTe 2by TEM, Fig. 4a shows LEED taken on the sample surface. As

  13. Thermoelectric probe for Fermi surface topology in the three-dimensional Rashba semiconductor BiTeI

    E-Print Network [OSTI]

    Ideue, T.

    We have investigated thermoelectric properties of a three-dimensional Rashba system BiTeI. Magnetic-field dependences of the Seebeck effect and Nernst effect show qualitative changes with the Fermi level passing through ...

  14. Rare-earth-rich tellurides: Gd{sub 4}NiTe{sub 2} and Er{sub 5}M{sub 2}Te{sub 2} (M=Co, Ni)

    SciTech Connect (OSTI)

    Magliocchi, Carmela; Meng, Fanqin; Hughbanks, Timothy . E-mail: trh@mail.chem.tamu.edu

    2004-11-01

    Three new rare earth metal-rich compounds, Gd{sub 4}NiTe{sub 2}, and Er{sub 5}M{sub 2}Te{sub 2} (M=Ni, Co), were synthesized in direct reactions using R, R{sub 3}M, and R{sub 2}Te{sub 3} (R=Gd, Er; M=Co, Ni) and single-crystal structures were determined. Gd{sub 4}NiTe{sub 2} is orthorhombic and crystallizes in space group Pnma with four formula units per cell. Lattice parameters at 110(2)K are a=15.548(9), b=4.113(2), c=11.7521(15)A. Er{sub 5}Ni{sub 2}Te{sub 2} and Er{sub 5}Co{sub 2}Te{sub 2} are isostructural and crystallize in the orthorhombic space group Cmcm with two formula units per cell. Lattice parameters at 110(2)K are a=3.934(1), b=14.811(4), c=14.709(4)A, and a=3.898(1), b=14.920(3), c=14.889(3)A, respectively. Metal-metal bonding correlations were analyzed using the empirical Pauling bond order concept.

  15. Analysis of chemically deposited CdSe and CdS thin films

    E-Print Network [OSTI]

    Osuji, R U

    2002-01-01

    We have successfully deposited quality polycrystalline thin films of CdSe and CdS on Corning 7059 glass slides by the electroless chemical bath technique at room temperature (~27 $^\\circ$C). X-ray analysis confirmed the successful deposition of CdSe and CdS thin films. Our grown CdSe film thickness ranged from 0.10 $\\mu$m. to 0.80 $\\pm$ 0.01 $\\mu$m and the CdS film thickness ranged from 0.10 $\\mu$m to 1.00 $\\pm$ 0.01 $\\mu$m. The scanning electron micrograph of the films reveals uniform film surface. The energy gaps, $E_g$ determined for our CdSe and CdS films have average values of 1.70 $\\pm$ 0.04 eV and 2.15 $\\pm$ 0.04 eV respectively. The films have high absorbance in the 0.35 $\\mu$m - 0.85 $\\mu$m range. These qualities make them suitable for use in thin film solar cell technology.

  16. DISTRIBUTED POSE AVERAGING IN CAMERA NETWORKS VIA CONSENSUS ON SE(3) Roberto Tron, Rene Vidal

    E-Print Network [OSTI]

    DISTRIBUTED POSE AVERAGING IN CAMERA NETWORKS VIA CONSENSUS ON SE(3) Roberto Tron, Ren´e Vidal distributed algorithms for esti- mating the average pose of an object viewed by a localized network of camera networks; pose estimation; consensus; optimization on manifolds. 1. INTRODUCTION Recent hardware

  17. SE-LEGO: Creating Metasearch Engines on Demand Zonghuan Wu, Vijay Raghavan,

    E-Print Network [OSTI]

    Meng, Weiyi

    SE-LEGO: Creating Metasearch Engines on Demand Zonghuan Wu, Vijay Raghavan, Chun Du, Komanduru Sai Keywords: Metasearch Engine, Metasearcher, search engine Extended Abstract As a system that provides unified access to multiple existing search systems, a metasearch engine can alleviate ordinary users from

  18. Long FRC Equilibrium and Stability Toward a Theory of S*/E Scaling D. C. Barnes*

    E-Print Network [OSTI]

    Washington at Seattle, University of

    Long FRC Equilibrium and Stability ­ Toward a Theory of S*/E Scaling D. C. Barnes* Los Alamos-reversed configurations (FRC's) is solved by an expansion in the small parameter (inverse elongation). The main results, to appear Phys. Plasmas]; 2) there are two classes of potentially unstable modes, transverse and axial, both

  19. T-558: Oracle Java SE and Java for Business Critical Patch Update Advisory- February 2011

    Broader source: Energy.gov [DOE]

    This Critical Patch Update contains 21 new security fixes for Oracle Java SE and Java for Business. 19 of these vulnerabilities may be remotely exploitable without authentication, i.e., may be exploited over a network without the need for a username and password.

  20. T-641: Oracle Java SE Critical Patch Update Advisory- June 2011

    Broader source: Energy.gov [DOE]

    This Critical Patch Update contains 17 new security fixes for Oracle Java SE - 5 apply to client and server deployments of Java SE, 11 apply to client deployments of Java SE only, and 1 applies to server deployments of Java SE only. All of these vulnerabilities may be remotely exploitable without authentication, i.e., may be exploited over a network without the need for a username and password. Oracle CVSS scores assume that a user running a Java applet or Java Web Start application has administrator privileges (typical on Windows). Where the user does not run with administrator privileges (typical on Solaris and Linux), the corresponding CVSS impact scores for Confidentiality, Integrity, and Availability are "Partial" instead of "Complete", and the corresponding CVSS Base score is 7.5 instead of 10 respectively. For issues in Deployment, fixes are only made available for JDK and JRE 6. Users should use the Java Web Start in JRE 6 and the new Java Plug-in introduced in 6 Update 10. CVE-2011-0862, CVE-2011-0873, CVE-2011-0815, CVE-2011-0817, CVE-2011-0863, CVE-2011-0864, CVE-2011-0802, CVE-2011-0814, CVE-2011-0871, CVE-2011-0786, CVE-2011-0788, CVE-2011-0866, CVE-2011-0868, CVE-2011-0872, CVE-2011-0867, CVE-2011-0869, and CVE-2011-0865

  1. FI 10 19 dcembre 2006 page Alan Turing se fraye un chemin jusqu'

    E-Print Network [OSTI]

    Teuscher, Christof

    FI 10 ­ 19 décembre 2006 ­ page Alan Turing se fraye un chemin jusqu'à la place de lPiccard,cheminJeanTschumi,avenueForel,rue RobertMercier,chemin, place ou rueAlanTuring. EtquefaisaitAlanTuringcheminfaisant?Leplus souvent,craqueurducodesecretdela machineEnigma?Certesexagéré,maisle succèsaplusieursparentsetAlanTuring estaumoinslegrandpèreoul

  2. R. Bchela,b, S.E. Pratsinisa, A. Baikerb Two-Nozzle Flame Synthesis of

    E-Print Network [OSTI]

    Daraio, Chiara

    R. Büchela,b, S.E. Pratsinisa, A. Baikerb Two-Nozzle Flame Synthesis of NOx Storage- Reduction and Bioengineering , ETH Zurich, CH-8092 Zurich, Switzerland NOx storage reduction (NSR) catalysts are used) the corresponding light-off Particle production NOx storage and reduction Objective 0 20 40 60 80 100 3) after

  3. Oceanography Vol.19, No. 3, Sept. 200664 Oceanography Vol.19, No. 3, Se64 Currents, Eddies,

    E-Print Network [OSTI]

    Rhode Island, University of

    Oceanography Vol.19, No. 3, Sept. 200664 Oceanography Vol.19, No. 3, Se64 Currents, Eddies. For a comprehensive re- view of the circulation in the region, see Chang et al. (2004). Oceanography Vol.19, No. 3 ThisarticlehasbeenpublishedinOceanography,Volume19,Number3,aquarterlyjournalofTheOceanographySociety.Copyright2006byTheOceanography

  4. Photovoltaic effect in InSe Application to Solar Energy Conversion

    E-Print Network [OSTI]

    Boyer, Edmond

    253 Photovoltaic effect in InSe Application to Solar Energy Conversion A. Segura, J. P. Guesdon, J are reported. Photovoltaic spectra are fitted with measured values oftransport and optical parameters. In possibilities as a material for photovoltaic cells. Transport in indium selenide shows a large ani- sotropy

  5. El tratamiento con cloro es un mtodo para desinfectar un pozo de agua. Se recomien-

    E-Print Network [OSTI]

    El tratamiento con cloro es un método para desinfectar un pozo de agua. Se recomien- da cuando un sistema de agua está contam- inado con bacterias. La contaminación puede ocurrir en la instalación del exceso de lluvia entran en el pozo. Si el agua subterránea constituye en sí la fuente de bacterias, el

  6. Al tratamiento del agua potable para mejo-rar su sanidad o calidad bacteriolgica se

    E-Print Network [OSTI]

    Al tratamiento del agua potable para mejo- rar su sanidad o calidad bacteriológica se le refiere desinfección usado por los proveedores locales para disminuir la contami- nación bacteriológica del agua. Este método tam- bién puede ser usado por los propietarios de pozos de agua particulares. Pozos de agua Los

  7. Molecular beam epitaxial growth of Bi{sub 2}Se{sub 3} nanowires and nanoflakes

    SciTech Connect (OSTI)

    Knebl, G. M. Gessler, J. R.; Kamp, M.; Höfling, S.

    2014-09-29

    Topological Insulators are in focus of immense research efforts and rapid scientific progress is obtained in that field. Bi{sub 2}Se{sub 3} has proven to be a topological insulator material that provides a large band gap and a band structure with a single Dirac cone at the ?-point. This makes Bi{sub 2}Se{sub 3} one of the most promising three dimensional topological insulator materials. While Bi{sub 2}Se{sub 3} nanowires and nanoflakes so far were fabricated with different methods and for different purposes, we here present the first Bi{sub 2}Se{sub 3} nanowires as well as nanoflakes grown by molecular beam epitaxy. The nanostructures were nucleated on pretreated, silicon (100) wafers. Altering the growth conditions nanoflakes could be fabricated instead of nanowires; both with high crystalline quality, confirmed by scanning electron microscopy as well as transmission electron microscopy. These nanostructures have promise for spintronic devices and Majorana fermion observation in contact to superconductor materials.

  8. Stability of S and Se induced reconstructions on GaP(001)(2×1) surface

    SciTech Connect (OSTI)

    Li , D. F.; Guo, Zhi C.; Xiao, Hai Yan; Zu, Xiaotao T.; Gao, Fei

    2010-10-15

    The structural and electronic properties of S- and Se- passivated GaP(001)(2×1) surfaces were studied using first-principles simulations. Our calculations showed that the most stable structure consists of a single chalcogen atom (S or Se) in the first crystal layer, which is bonded to two Ga atoms of the second layer, and the third P layer replaced by chalcogen atoms, similar to the passivation of GaAs(001)(2×1) surface by chalcogen atoms. The structural parameters were determined and the surface band characters and the local density of states were also analyzed. The results showed that the preferable structure has no surface states in the bulk band gap, but the energy band gaps of the S- and Se-adsorbed GaP(001) surfaces are 1.83eV and 1.63eV, respectively. The passivation effects for the S- and Se-adsorbed surfaces are similar to each other.

  9. A highly efficient (>6%) Cd1xMnxSe quantum dot sensitized solar cell

    E-Print Network [OSTI]

    Cao, Guozhong

    , suffer from high cost of manufacturing and installation. Now the focus is on next generation solar cellsA highly efficient (>6%) Cd1ÀxMnxSe quantum dot sensitized solar cell Jianjun Tian,*a Lili Lv,a Chengbin Fei,b Yajie Wang,b Xiaoguang Liua and Guozhong Cao*bc Quantum dot sensitized solar cells (QDSCs

  10. Diffusion of indium and gallium in Cu(In,Ga)Se2 thin film solar cells

    E-Print Network [OSTI]

    Rockett, Angus

    Diffusion of indium and gallium in Cu(In,Ga)Se2 thin film solar cells O. Lundberga,*, J. Lua , A conversion efficiency of solar cells made from this material [1]. One of the special qualities of the CIGS improve the solar cell performance. In many of the different CIGS fabrication techniques, an in depth

  11. Tetrapod localities from the Triassic of the SE of European Russia Valentin P. Tverdokhlebova

    E-Print Network [OSTI]

    Benton, Michael

    of the southern Urals area of European Russia. The first sites were found in the 1940s, and subsequent surveys B.V. All rights reserved. Keywords: Permian; Triassic; Tetrapod; Amphibian; Reptile; Russia; UralsTetrapod localities from the Triassic of the SE of European Russia Valentin P. Tverdokhlebova

  12. The Single Most Polymorphic STR Locus: SE33 Performance in U.S. Populations

    E-Print Network [OSTI]

    http://www.cstl.nist.gov/biotech/strbase john.butler@nist.gov http://www.dna.gov/research/nist Buenos of the SE33 repeat region. Poster available for download from STRBase: http://www.cstl.nist.gov/biotech Biotech, Ft. Lauderdale, FL). A total of 400 father-son sample pairs were provided by DNA Diagnostics

  13. Characterization of an FFDM unit based on a-Se direct conversion detector

    E-Print Network [OSTI]

    Lanconelli, Nico

    Characterization of an FFDM unit based on a-Se direct conversion detector Achille Albanese1 of this paper is to investigate the properties of a clinical FFDM unit (Giotto - Image MD, IMS Italy µm. The direct conversion of X-rays into charge provides excellent imaging performance. In this work

  14. U .Se Weather Bureau. Hurricane Daisy, September 30-October 7, 1062

    E-Print Network [OSTI]

    QC 945.2 U .Se Weather Bureau. Hurricane Daisy, September 30- October 7, 1062 #12;National Oceanic and Atmospheric Administration Weather Bureau Hurricane Series ERRATA NOTICE One-1387 November 6,2007 #12;OF COMMERCE WEATHER BUREAU LlBRARY JUL 0 5 2001 121 533 #12;HURRICANE DAISY SEPTEMBER

  15. Electrodeposition of CuGaSe2 from Thiocyanate-Containing Electrolytes

    E-Print Network [OSTI]

    Suni, Ian Ivar

    . Manuscript received September 8, 2010. Published December 2, 2010. CuInxGa1-xSe2 CIGS thin film solar cells- nation velocities.1 Thin film solar cells promise significant economic benefits, because the optical, electrochemical deposition methods may be significantly less expensive for scale-up of thin film solar cells,3

  16. Oceanography Vol.23, No.124 MouNtaiNs iN the se a

    E-Print Network [OSTI]

    Sandwell, David T.

    Oceanography Vol.23, No.124 MouNtaiNs iN the se a The Global seamount Census By Pau l We s sel , DaVi estimates for the global census of seamounts. BathyMetriC seaMouNt stuDies Bill Menard began the modern era

  17. Tunable White-Light-Emitting Mn-Doped ZnSe Nanocrystals Vijay Kumar Sharma,

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    Se-related blue emission (410 and 435 nm), Zn-related defect state green emission (520 nm), and Mn-dopant related for the purpose of generation of photometrically high quality white light while maintaining the energy efficiency is to combine red-, green-, and blue-emitting NCs in an appropriate ratio.1,2 However, when one simply mixes

  18. Hydrogen adsorption on Pd/TiFe (110) surface S.E. Kulkovaa

    E-Print Network [OSTI]

    Kim, Jai Sam

    Hydrogen adsorption on Pd/TiFe (110) surface S.E. Kulkovaa , S.V. Eremeeva,b,*, V.E. Egorushkinc February 2003 by E.L. Ivchenko Abstract Adsorption of hydrogen on the TiFe (110) surface covered. Electronic band structure 1. Introduction The TiFe alloy is an excellent material for hydrogen storage [1

  19. SE-CSE 2009: The Second International Workshop on Software Engineering for Computational Science and Engineering

    E-Print Network [OSTI]

    Carver, Jeffrey C.

    SE-CSE 2009: The Second International Workshop on Software Engineering for Computational Science with the development of Computational Science & Engineering (CS&E) software. This software includes: 1) Scientific, the development of CS&E software has historically attracted little attention from the software engineering

  20. MAE 130A / SE 101A (4 units) Mechanics I: Statics

    E-Print Network [OSTI]

    Fainman, Yeshaiahu

    MAE 130A / SE 101A (4 units) Mechanics I: Statics Class/Laboratory Schedule: four hours of lecture/Materials: 1. Beer and Johnston, Vector Mechanics for Engineers - Statics, McGraw-Hill, 2012, 10th ed. 2. Hibbeler, R.C., "Engineering Mechanics: Statics", Pearson Prentice Hall, 2010, 12th ed. Catalog Description

  1. Statistical Mechanics, CHEM 6481, Fall MWF 10:05-10:55am, MoSE 1224

    E-Print Network [OSTI]

    Sherrill, David

    Statistical Mechanics, CHEM 6481, Fall MWF 10:05-10:55am, MoSE 1224 Course website: T-Square Prerequisites: Advanced quantum mechanics (can be taken concurrently), advanced thermodynamics, multivariate" are considered background material. Required Text: "Introduction to Modern Statistical Mechanics," David Chandler

  2. To appear in JSiSE, 18(2), 2001 July 30, 2001

    E-Print Network [OSTI]

    Matsuda, Noboru

    To appear in JSiSE, 18(2), 2001 July 30, 2001 1. (Intelligent Tutoring System: ITS) () "" 2. Graesser (1995) Chi (2001 to appear) #12;Graesser Chi Graesser 70 Chi Graesser Chi ITS ITS "" 3. (Graesser , 2001 to appear) - Building Dialogue Systems for Tutoring

  3. Crystal structure of the new FeSe1-x superconductor 

    E-Print Network [OSTI]

    Margadonna S.; McDonald M.T.; Kasperkiewicz K.; Mizuguchi Y.; Takano Y.; Fitch A.N.; Suard E.; Prassides K.; Takabayashi Y.

    2008-01-01

    The newly discovered superconductor FeSe1-x (x approximate to 0.08, T-c(onset) approximate to 13.5 K at ambient pressure rising to 27 K at 1.48 GPa) exhibits a structural phase transition from tetragonal to orthorhombic ...

  4. Se cumple la regla de Hamilton? Cuando Charles Darwin propuso la teora de la evo-

    E-Print Network [OSTI]

    Machado, Carlos A.

    de reproducirse. En la naturaleza abundan las muestras de altruismo. Pensemos, por ejemplo, en los parentesco ("kin selection"). Esta tesis la esbozó, a mediados de los años se- senta, William Donald Hamilton reducción de comportamientos agre- sivos o de competencia entre congéneres. El núcleo central de dicha tesis

  5. Mn-Substituted Inorganic-Organic Hybrid Materials Based on ZnSe

    E-Print Network [OSTI]

    Li, Jing

    Mn-Substituted Inorganic-Organic Hybrid Materials Based on ZnSe: Nanostructures That May Lead research that deals with synthesis, characterization, and modification of organic-inorganic hybrid to integrate functional materials that utilize both electron charge and spin.1 Thus, the introduction

  6. Electronic structure of the Si(111):GaSe van der Waals-like surface termination

    E-Print Network [OSTI]

    Olmstead, Marjorie

    Electronic structure of the Si(111):GaSe van der Waals-like surface termination Reiner Rudolph-like surface termination has been determined by angle-resolved photoelectron spectroscopy using photons. This explains both the absence of a surface core-level shift in Si 2p photoelectron spectra of the terminated

  7. Deformation regime variations in an arcuate transpressional orogen (Ribeira belt, SE Brazil) imaged by anisotropy of

    E-Print Network [OSTI]

    Bascou, Jérôme

    Deformation regime variations in an arcuate transpressional orogen (Ribeira belt, SE Brazil) imaged Paulo, Brazil b Laboratoire de Tectonophysique, Universite´ de Montpellier II CNRS, Montpellier, France Instituto de Geocie^ncias, Universidade Federal de Minas Gerais, Minas Gerais, Brazil Received 23 September

  8. Holocene tephra from Iceland and Alaska in SE Greenland Shelf Sediments

    E-Print Network [OSTI]

    Stoner, Joseph

    Holocene tephra from Iceland and Alaska in SE Greenland Shelf Sediments ANNE JENNINGS1*, THORVALDURJW, UK 3 Faculty of Earth Sciences, University of Iceland, Askja, Sturlugata 7, Reykjavi´k 101, Iceland 4 College of Earth Ocean and Atmospheric Sciences, Oregon State University 104 COAS Admin Building

  9. Nanofabrication, Plasmon Enhanced Fluorescence and Photo-oxidation Kinetics of CdSe Nanoparticles 

    E-Print Network [OSTI]

    Chen, Jixin

    2011-08-08

    by these techniques include the metal nanoparticle arrays, and the self-assembled CdSe nanoring arrays. At the same time, the dissertation provides mechanisms and models to describe the physical and chemical nature of these techniques. The second area of this study...

  10. Summary for FT, IT and SE 20th IAEA Fusion Energy Conference

    E-Print Network [OSTI]

    Summary for FT, IT and SE 20th IAEA Fusion Energy Conference 1 - 6 November 2004 Vilamoura on Plasma Physics and controlled Nuclear Fusion Research has been changed to be IAEA Fusion Energy and should be moved to the ultimat goal of utilizing fusion energy for human being in near future

  11. MAE 130C / SE 101C (4 units) Mechanics III: Vibrations

    E-Print Network [OSTI]

    Fainman, Yeshaiahu

    MAE 130C / SE 101C (4 units) Mechanics III: Vibrations Class/Laboratory Schedule: four hours Textbooks/Materials: 1. S.S. Rao: Mechanical Vibrations, 4th ed., Prentice Hall, 2010 2. W.T. Thomson and M.D. Dahleh, Theory of Vibrations with Applications, 5th ed., Prentice Hall, 1997 3. L. Meirovitch

  12. Cu(In,Ga)Se2based Photovoltaics: Challenges and Opportunities

    E-Print Network [OSTI]

    Firestone, Jeremy

    Cu(In,Ga)Se2­based Photovoltaics: Challenges and Opportunities William Shafarman Institute of Energy Conversion University of Delaware #12;Thin Film Photovoltaics Potential for low cost PV using a Thickness K.Kim, et al., IEEE J. Photovoltaics, 3, 446 (2013). 2 µm, 60 min reaction 1 µm, 25 min reaction 0

  13. Contractional deformation of porous sandstone: Insights from the Aztec Sandstone, SE Nevada, USA

    E-Print Network [OSTI]

    Fossen, Haakon

    Contractional deformation of porous sandstone: Insights from the Aztec Sandstone, SE Nevada, USA Available online 19 March 2015 Keywords: Sevier thrusting Porous sandstone deformation Deformation bands Contractional deformation a b s t r a c t Contractional deformation of highly porous sandstones is poorly

  14. Study of light-induced vector changes in the local atomic structure of AsSe glasses by EXAFS

    E-Print Network [OSTI]

    Drabold, David

    Study of light-induced vector changes in the local atomic structure of As­Se glasses by EXAFS G changes in the local structure of As­Se glasses using extended X-ray ab- sorption fine structure (EXAFS

  15. Manufacturable CuIn(Ga)Se{sub 2}-based solar cells via development of co-sputtered CuInSe{sub 2} absorber layers

    SciTech Connect (OSTI)

    Dr. Ingrid Eisgruber

    1999-03-20

    Yield and reproducibility remain issues in CuIn(Ga)Se{sub 2} (CIGS) photovoltaic module fabrication. While small-area cells (<1 cm{sup 2}) over 18% efficient have been reported, the best large-area manufactured devices (>1 ft{sup 2}) are 11% efficient with about 60% yield. If improvements in large-area manufacturing can accomplish 15% efficiency and 90% yield, the result is a doubling in throughput leading to a reduction in cost per watt of over 50%. The challenge now facing the photovoltaics industry is to bring the efficiencies of small-area cells and large-area industrial modules closer together and to raise manufacturing yields.

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

    SciTech Connect (OSTI)

    Albin, D.; del Cueto, J.

    2011-03-01

    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.

  17. Nanostructured Ge{sub 2}Sb{sub 2}Te{sub 5} chalcogenide films produced by laser electrodispersion

    SciTech Connect (OSTI)

    Yavsin, D. A., E-mail: yavsin@mail.ioffe.ru; Kozhevin, V. M.; Gurevich, S. A.; Yakovlev, S. A.; Melekh, B. T.; Yagovkina, M. A.; Pevtsov, A. B. [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)

    2014-12-15

    Amorphous nanostructured films of a complex chalcogenide (Ge{sub 2}Sb{sub 2}Te{sub 5}) are produced by laser electrodispersion and their structural and electrical properties are studied. It is found that the characteristic size of Ge{sub 2}Sb{sub 2}Te{sub 5} nanoparticles in the structure of the films is 1.5–5 nm.

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

    SciTech Connect (OSTI)

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

    2007-04-01

    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.

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

    SciTech Connect (OSTI)

    Ozturk, Sertac; /Cukurova U.

    2011-03-01

    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.

  20. High Efficiency Thin Film CdTe and a-Si Based Solar Cells Final Technical Report for the Period

    E-Print Network [OSTI]

    Deng, Xunming

    High Efficiency Thin Film CdTe and a-Si Based Solar Cells Final Technical Report for the PeriodTe-based thin-film solar cells and on high efficiency a-Si-based thin-film solar cells. Phases I and II have-SiGe bottom cells. · Studied the sputter deposition of ITO films for the top electrode on a-Si cells and found

  1. First-principles calculation of the bulk photovoltaic effect in the polar compounds LiAsS2, LiAsSe2, and NaAsSe2

    E-Print Network [OSTI]

    Rappe, Andrew M.

    by the AIP Publishing Articles you may be interested in (Sr,Ba)(Si,Ge)2 for thin-film solar-cell applications effects on atomic bonding and electronic properties at HfO2/GaAs interface: A first-principles study J.g., Si, CdTe, CIGS, and GaAs), in order for a material to exhibit a signif- icant BPVE response from

  2. Fabrication of fluorescent composite with ultrafast aqueous synthesized high luminescent CdTe quantum dots

    SciTech Connect (OSTI)

    Zhang, Lei, E-mail: mejswu@ust.hk; Chen, Haibin, E-mail: mejswu@ust.hk, E-mail: mejswu@ust.hk; Wu, Jingshen, E-mail: mejswu@ust.hk, E-mail: mejswu@ust.hk [Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Hong Kong and Fok Ying Tung Graduate School, The Hong Kong University of Science and Technology (Hong Kong); Bi, Xianghong, E-mail: takubatch@gmail.com [Fok Ying Tung Graduate School, The Hong Kong University of Science and Technology (Hong Kong)

    2014-05-15

    Without precursor preparation, inert gas protection and enormous amount of additives and reductants, CdTe quantum dots (QDs) can be rapidly synthesized with high quality. A 600 nm photoluminescence peak wavelength could be obtained within 1 hour's refluxing through minimal addition of 1,2-diaminoethane (DAE). The theoretical design for the experiments are illustrated and further proved by the characterization results with different concentrations and reagents. On the other hand, generation of CdTe QDs was found even under room temperature by applying droplet quantity of DAE. This indicates that QDs can be synthesized with simply a bottle and no enormous additives required. The QDs were mixed into the epoxy matrix through solution casting method with cetyltrimethylammonium (CTA) capping for phase transfer. The acquired epoxy based nanocomposite exhibits good transparency, compatibility and fluorescence.

  3. Characterization of a large CdZnTe coplanar quad-grid semiconductor detector

    E-Print Network [OSTI]

    The COBRA collaboration; Joachim Ebert; Claus Gößling; Daniel Gehre; Caren Hagner; Nadine Heidrich; Rainer Klingenberg; Kevin Kröninger; Christian Nitsch; Christian Oldorf; Thomas Quante; Silke Rajek; Henning Rebber; Katja Rohatsch; Jan Tebrügge; Robert Temminghoff; Robert Theinert; Jan Timm; Björn Wonsak; Stefan Zatschler; Kai Zuber

    2015-09-08

    The COBRA collaboration aims to search for neutrinoless double beta-decay of $^{116}$Cd. A demonstrator setup with 64 CdZnTe semiconductor detectors, each with a volume of 1cm$^3$, is currently being operated at the LNGS underground laboratory in Italy. This paper reports on the characterization of a large (2 $\\times$ 2 $\\times$ 1.5)cm$^3$ CdZnTe detector with a new coplanar-grid design for applications in $\\gamma$-ray spectroscopy and low-background operation. Several studies of electric properties as well as of the spectrometric performance, like energy response and resolution, are conducted. Furthermore, measurements including investigating the operational stability and a possibility to identify multiple-scattered photons are presented.

  4. Search for Dijet Resonances in 7 TeV pp Collisions at CMS

    SciTech Connect (OSTI)

    Khachatryan, V.; et al.

    2010-11-01

    A search for narrow resonances in the dijet mass spectrum is performed using data corresponding to an integrated luminosity of 2.9 inverse pb collected by the CMS experiment at the LHC. Upper limits at the 95% confidence level (CL) are presented on the product of the resonance cross section, branching fraction into dijets, and acceptance, separately for decays into quark-quark, quark-gluon, or gluon-gluon pairs. The data exclude new particles predicted in the following models at the 95% CL: string resonances, with mass less than 2.50 TeV, excited quarks, with mass less than 1.58 TeV, and axigluons, colorons, and E_6 diquarks, in specific mass intervals. This extends previously published limits on these models.

  5. Electronic structure reconstruction across the antiferromagnetic transition in TaFe????Te? spin ladder

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Xu, Min; Wang, Li -Min; Peng, Rui; Ge, Qing -Qin; Chen, Fei; Ye, Zi -Rong; Zhang, Yan; Chen, Su -Di; Xia, Miao; Liu, Rong -Hua; et al

    2015-02-01

    With angle-resolved photoemission spectroscopy, we studied the electronic structure of TaFe????Te?, a two-leg spin ladder compound with a novel antiferromagnetic ground state. Quasi-two-dimensional Fermi surface is observed, with sizable inter-ladder hopping. Moreover, instead of observing an energy gap at the Fermi surface in the antiferromagnetic state, we observed the shifts of various bands. Combining these observations with density-functional-theory calculations, we propose that the large scale reconstruction of the electronic structure, caused by the interactions between coexisting itinerant electrons and local moments, is most likely the driving force of the magnetic transition. Thus TaFe????Te? serves as a simpler platform that containsmore »similar ingredients as the parent compounds of iron-based superconductors.« less

  6. Discovery of Diffuse TeV Gamma-Ray Emission from the Galactic Plane

    E-Print Network [OSTI]

    Fleysher, R; Benbow, W; Berley, D; Blaufuss, E; Coyne, D G; De Young, T R; Dingus, B L; Dorfan, D E; Ellsworth, R W; Fleysher, L; Gisler, G; González, M M; Goodman, J A; Haines, T J; Hays, E; Hoffman, C M; Kelley, L A; Lansdell, C P; Linnemann, J T; McEnery, J E; Miller, R S; Mincer, A I; Morales, M F; Némethy, P; Noyes, D; Ryan, J M; Samuelson, F W; Saz-Parkinson, P M; Shoup, A; Sinnis, G; Smith, A J; Sullivan, G W; Williams, D A; Wilson, M E; Xu, X W; Yodh, G B

    2005-01-01

    Gamma-ray emission from a narrow band at the Galactic equator has previously been detected up to 30 GeV. We report the first observation of a diffuse Galactic plane gamma-ray signal at TeV energies by Milagro, a large field of view water Cherenkov detector for extensive air showers. An excess with a significance of 4.5 sigma has been observed from the region of Galactic longitude 40 1TeV) = 5.1 +/-1.0 +/-1.7 10^{-10} cm^{-2}s^{-1} sr^{-1}$. This flux is below, but consistent with, an extrapolation of the EGRET spectrum between 1 and 30 GeV in this Galactic region.

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

    E-Print Network [OSTI]

    R. Atkins; W. Benbow; D. Berley; M. -L. Chen; D. G. Coyne; R. S. Delay; B. L. Dingus; D. E. Dorfan; R. W. Ellsworth; D. Evans; A. Falcone; L. Fleysher; R. Fleysher; G. Gisler; J. A. Goodman; T. J. Haines; C. M. Hoffman; S. Hugenberger; L. A. Kelley; I. Leonor; J. Macri; M. McConnell; J. F. McCullough; J. E. McEnery; R. S. Miller; A. I. Mincer; M. F. Morales; P. Nemethy; J. M. Ryan; M. Schneider; B. Shen; A. Shoup; G. Sinnis; A. J. Smith; G. W. Sullivan; T. N. Thompson; O. T. Tumer; K. Wang; M. O. Wascko; S. Westerhoff; D. A. Williams; T. Yang; G. B. Yodh

    1999-06-24

    The Milagrito water Cherenkov telescope operated for over a year. The most probable gamma-ray energy was ~1 TeV and the trigger rate was as high as 400 Hz. We have developed an efficient technique for searching the entire sky for short duration bursts of TeV photons. Such bursts may result from "traditional" gamma-ray bursts that were not in the field-of-view of any other instruments, the evaporation of primordial black holes, or some as yet undiscovered phenomenon. We have begun to search the Milagrito data set for bursts of duration 10 seconds. Here we will present the technique and the expected results. Final results will be presented at the conference.

  8. Search for Short Duration Bursts of TeV $\\gamma$ Rays with the Milagrito Telescope

    E-Print Network [OSTI]

    Atkins, R; Berley, D; Chen, M L; Coyne, D G; Delay, R S; Dingus, B L; Dorfan, D E; Ellsworth, R W; Evans, D; Falcone, A D; Fleysher, L; Fleysher, R; Gisler, G; Goodman, J A; Haines, T J; Hoffman, C M; Hugenberger, S; Kelley, L A; Leonor, I; Macri, J R; McConnell, M; McCullough, J F; McEnery, J E; Miller, R S; Mincer, A I; Morales, M F; Némethy, P; Ryan, J M; Schneider, M; Shen, B; Shoup, A L; Sinnis, G; Smith, A J; Sullivan, G W; Thompson, T N; Tümer, T O; Wang, K; Wascko, M O; Westerhoff, S; Williams, D A; Yang, T; Yodh, G B

    1999-01-01

    The Milagrito water Cherenkov telescope operated for over a year. The most probable gamma-ray energy was ~1 TeV and the trigger rate was as high as 400 Hz. We have developed an efficient technique for searching the entire sky for short duration bursts of TeV photons. Such bursts may result from "traditional" gamma-ray bursts that were not in the field-of-view of any other instruments, the evaporation of primordial black holes, or some as yet undiscovered phenomenon. We have begun to search the Milagrito data set for bursts of duration 10 seconds. Here we will present the technique and the expected results. Final results will be presented at the conference.

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

    SciTech Connect (OSTI)

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

    2008-06-02

    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.

  10. Search for Neutrinoless Double-Beta Decay of $^{130}$Te with CUORE-0

    E-Print Network [OSTI]

    K. Alfonso; D. R. Artusa; F. T. Avignone III; O. Azzolini; M. Balata; T. I. Banks; G. Bari; J. W. Beeman; F. Bellini; A. Bersani; M. Biassoni; C. Brofferio; C. Bucci; A. Caminata; L. Canonica; X. G. Cao; S. Capelli; L. Cappelli; L. Carbone; L. Cardani; N. Casali; L. Cassina; D. Chiesa; N. Chott; M. Clemenza; S. Copello; C. Cosmelli; O. Cremonesi; R. J. Creswick; J. S. Cushman; I. Dafinei; A. Dally; S. Dell'Oro; M. M. Deninno; S. DiDomizio; M. L. DiVacri; A. Drobizhev; L. Ejzak; D. Q. Fang; M. Faverzani; G. Fernandes; E. Ferri; F. Ferroni; E. Fiorini; S. J. Freedman; B. K. Fujikawa; A. Giachero; L. Gironi; A. Giuliani; P. Gorla; C. Gotti; T. D. Gutierrez; E. E. Haller; K. Han; E. Hansen; K. M. Heeger; R. Hennings-Yeomans; K. P. Hickerson; H. Z. Huang; R. Kadel; G. Keppel; Yu. G. Kolomensky; K. E. Lim; X. Liu; Y. G. Ma; M. Maino; M. Martinez; R. H. Maruyama; Y. Mei; N. Moggi; S. Morganti; S. Nisi; C. Nones; E. B. Norman; A. Nucciotti; T. O'Donnell; F. Orio; D. Orlandi; J. L. Ouellet; C. E. Pagliarone; M. Pallavicini; V. Palmieri; L. Pattavina; M. Pavan; M. Pedretti; G. Pessina; V. Pettinacci; G. Piperno; S. Pirro; S. Pozzi; E. Previtali; C. Rosenfeld; C. Rusconi; E. Sala; S. Sangiorgio; D. Santone; N. D. Scielzo; M. Sisti; A. R. Smith; L. Taffarello; M. Tenconi; F. Terranova; C. Tomei; S. Trentalange; G. Ventura; M. Vignati; S. L. Wagaarachchi; B. S. Wang; H. W. Wang; L. Wielgus; J. Wilson; L. A. Winslow; T. Wise; L. Zanotti; C. Zarra; G. Q. Zhang; B. X. Zhu; S. Zucchelli

    2015-04-09

    We report the results of a search for neutrinoless double-beta decay in a 9.8~kg$\\cdot$yr exposure of $^{130}$Te using a bolometric detector array, CUORE-0. The characteristic detector energy resolution and background level in the region of interest are $5.1\\pm 0.3{\\rm~keV}$ FWHM and $0.058 \\pm 0.004\\,(\\mathrm{stat.})\\pm 0.002\\,(\\mathrm{syst.})$~counts/(keV$\\cdot$kg$\\cdot$yr), respectively. The median 90%~C.L. lower-limit sensitivity of the experiment is $2.9\\times 10^{24}~{\\rm yr}$ and surpasses the sensitivity of previous searches. We find no evidence for neutrinoless double-beta decay of $^{130}$Te and place a Bayesian lower bound on the decay half-life, $T^{0\

  11. Anti pp searches for quark-gluon plasma at TeV I

    SciTech Connect (OSTI)

    Turkot, F.

    1986-06-01

    Three experiments that have been approved to run at TeV I are discussed from the viewpoint of their capability to search for evidence of the QCD phase transition in proton-antiproton collisions at 1.6 TeV. One of these experiments, E-735, was proposed as a dedicated search for quark-gluon plasma effects with a detector designed to study large total E/sub T/, low P/sub T/ individual particles. The other two, E-741 (CDF) and E-740 (DO), embody general purpose four-pi detectors designed primarily to study the physics of W and Z bosons and other large P/sub T/ phenomena. The detectors and their quark-gluon plasma signals are compared. 8 refs., 6 figs., 4 tabs. (LEW)

  12. Observation of Anisotropy in the Arrival Direction Distribution of TeV Cosmic Rays with HAWC

    E-Print Network [OSTI]

    BenZvi, S Y; Westerhoff, S

    2015-01-01

    The High-Altitude Water Cherenkov (HAWC) Observatory, located 4100 m above sea level near Sierra Negra (19$^\\circ$ N) in Mexico, is sensitive to gamma rays and cosmic rays at TeV energies. The arrival direction distribution of cosmic rays at these energies shows significant anisotropy on several angular scales, with a relative intensity ranging between 10$^{-3}$ and 10$^{-4}$. We present the results of a study of cosmic-ray anisotropy based on more than 86 billion cosmic-ray air showers recorded with HAWC since June 2013. The HAWC cosmic-ray sky map, which has a median energy of 2 TeV, exhibits several regions of significantly enhanced cosmic-ray flux. We present the energy dependence of the anisotropy and the cosmic-ray spectrum in the regions of significant excess.

  13. Topological crystalline insulator Pb{sub x}Sn{sub 1-x}Te thin films on SrTiO{sub 3} (001) with tunable Fermi levels

    SciTech Connect (OSTI)

    Guo, Hua; Liu, Jun-Wei; Wang, Zhen-Yu; Wu, Rui; Ji, Shuai-Hua; Duan, Wen-Hui; Chen, Xi Xue, Qi-Kun; Yan, Chen-Hui; Zhang, Zhi-Dong; Wang, Li-Li; He, Ke; Ma, Xu-Cun

    2014-05-01

    In this letter, we report a systematic study of topological crystalline insulator Pb{sub x}Sn{sub 1-x}Te (0 < x < 1) thin films grown by molecular beam epitaxy on SrTiO{sub 3}(001). Two domains of Pb{sub x}Sn{sub 1-x}Te thin films with intersecting angle of ? ? 45° were confirmed by reflection high energy diffraction, scanning tunneling microscopy, and angle-resolved photoemission spectroscopy (ARPES). ARPES study of Pb{sub x}Sn{sub 1-x}Te thin films demonstrated that the Fermi level of PbTe could be tuned by altering the temperature of substrate whereas SnTe cannot. An M-shaped valance band structure was observed only in SnTe but PbTe is in a topological trivial state with a large gap. In addition, co-evaporation of SnTe and PbTe results in an equivalent variation of Pb concentration as well as the Fermi level of Pb{sub x}Sn{sub 1-x}Te thin films.

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

    SciTech Connect (OSTI)

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

    1996-01-01

    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.

  15. First-principles molecular-dynamics study of glassy As2Se3 Jun Li and D. A. Drabold

    E-Print Network [OSTI]

    Drabold, David

    static structure factor in the range 2­6 Å 1 . The preferred structural unit is pyramidal AsSe3 loosely on the cluster model8 consisting mostly of pyramidal AsSe3 molecules,9 and the other is the layer structure using a molecular model and several vibrational frequencies were assigned to pyramidal AsSe3

  16. Measurement of the underlying event activity at the LHC with $ \\sqrt {s} = 7 $ TeV and comparison with $ \\sqrt {s} = 0.9 $ TeV

    SciTech Connect (OSTI)

    Chatrchyan, Serguei; et al.

    2011-09-01

    A measurement of the underlying activity in scattering processes with a hard scale in the several GeV region is performed in proton-proton collisions at sqrt(s) = 0.9 and 7 TeV, using data collected by the CMS experiment at the LHC. The production of charged particles with pseudorapidity |eta| < 2 and transverse momentum pT > 0.5 GeV/c is studied in the azimuthal region transverse to that of the leading set of charged particles forming a track-jet. A significant growth of the average multiplicity and scalar-pT sum of the particles in the transverse region is observed with increasing pT of the leading track-jet, followed by a much slower rise above a few GeV/c. For track-jet pT larger than a few GeV/c, the activity in the transverse region is approximately doubled with a centre-of-mass energy increase from 0.9 to 7 TeV. Predictions of several QCD-inspired models as implemented in PYTHIA are compared to the data.

  17. Multiwavelength study of the northeastern outskirts of the extended TeV source HESS J1809–193

    SciTech Connect (OSTI)

    Rangelov, Blagoy; Kargaltsev, Oleg; Hare, Jeremy; Volkov, Igor; Posselt, Bettina; Pavlov, George G.

    2014-11-20

    HESS J1809–193 is an extended TeV ?-ray source in the Galactic plane. Multiwavelength observations of the HESS J1809–193 field reveal a complex picture. We present results from three Chandra X-Ray Observatory and two Suzaku observations of a region in the northeastern outskirts of HESS J1809-193, where enhanced TeV emission has been reported. Our analysis also includes GeV ?-ray and radio data. One of the X-ray sources in the field is the X-ray binary XTE J1810-189, for which we present the outburst history from multiple observatories and confirm that XTE J1810-189 is a strongly variable type I X-ray burster, which can hardly produce TeV emission. We investigate whether there is any connection between the possible TeV extension of HESS J1809–193 and the sources seen at lower energies. We find that another X-ray binary candidate, Suzaku J1811-1900, and a radio supernova remnant, SNR G11.4–0.1, can hardly be responsible for the putative TeV emission. Our multiwavelength classification of fainter X-ray point sources also does not produce a plausible candidate. We conclude that the northeast extension of HESS J1809–193, if confirmed by deeper observations, can be considered a dark accelerator—a TeV source without a visible counterpart at lower energies.

  18. Dijet Azimuthal Decorrelations in pp Collisions at sqrt(s) = 7 TeV

    SciTech Connect (OSTI)

    Khachatryan, Vardan; et al.

    2011-03-01

    Measurements of dijet azimuthal decorrelations in pp collisions at sqrt(s) = 7 TeV using the CMS detector at the CERN LHC are presented. The analysis is based on an inclusive dijet event sample corresponding to an integrated luminosity of 2.9 inverse picobarns. The results are compared to predictions from perturbative QCD calculations and various Monte Carlo event generators. The dijet azimuthal distributions are found to be sensitive to initial-state gluon radiation.

  19. New acceptor centers of the background impurities in p-CdZnTe

    SciTech Connect (OSTI)

    Plyatsko, S. V. Rashkovetskyi, L. V.

    2013-07-15

    Low-temperature photoluminescence data are used to study the redistribution of the background impurities and host components of p-CdZnTe single crystals with a resistivity of 1-50 {Omega} cm upon their interaction with infrared laser radiation. The effect of widening of the band gap and the formation of new acceptor centers in response to laser-stimulated changes in the system of intrinsic defects are established. The activation energy of the new acceptor centers is determined.

  20. Natural Cutoffs effect on Charged Rotating TeV-Scale Black Hole Thermodynamics

    E-Print Network [OSTI]

    M. J. Soleimani; N. Abbasvandi; G. Gopir; Zainol Abidin Ibrahim; Shahidan Radiman; W. A. T Wan Abdullah

    2015-10-15

    We study the thermodynamics of charged rotating black hole in large extra dimensions scenario where quantum gravity effects are taken into account. We consider the effects of minimal length, minimal momentum, and maximal momentum as natural cutoffs on the thermodynamics of charged rotating TeV-scale black holes. In this framework the effect of the angular momentum and charge on the thermodynamics of the black hole are discussed. We focus also on frame dragging and Sagnac effect of the micro black holes.

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

    E-Print Network [OSTI]

    C. Deluca

    2009-05-13

    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.

  2. Beam extraction from TeV accelerators using channeling in bent crystals

    SciTech Connect (OSTI)

    Carrigan, R.A. Jr.; Toohig, T.E.; Tsyganov, E.N.; Superconducting Super Collider Lab., Dallas, TX; Joint Inst. for Nuclear Research, Dubna )

    1989-08-01

    Bent crystal channeling offers an interesting alternative for beam extraction from trans-GeV accelerators. Conventional extraction employs resonant beam blow-up coupled with electromagnetic beam deflecting channels. It is limited by the length of the available accelerator straight section. Channeling crystals require much less space. A five-step approach to applying crystal extraction in the Superconducting Super Collider (SSC) is discussed. Two steps, extraction from the 8 GeV Dubna Synchrophasotron and the 76 GeV Serpukhov accelerator, have occurred. The next possibility is extraction from a multi-hundred GeV superconducting accelerator. In the nineties the program could continue at UNK (3 TeV) and culminate at the TeV SSC. The possibilities and limitations of crystal extraction are reviewed. More information is needed on dechanneling in bent crystals including the effects of dislocations at TeV energies. Long, dislocation-free'' crystals are required. A more thorough understanding of the theory of crystal extraction is also desirable. 12 refs.

  3. On the formation of TeV radiation in LS 5039

    E-Print Network [OSTI]

    Khangulyan, Dmitry; Bosch-Ramon, Valenti

    2007-01-01

    The recent detections of TeV gamma-rays from compact binary systems show that relativistic outflows (jets or winds) are sites of effective acceleration of particles up to multi-TeV energies. In this paper, we discuss the conditions of acceleration and radiation of ultra-relativistic electrons in LS 5039, currently the binary system emitting gamma-rays with the highest quality data in the TeV range. Assuming that the gamma-ray emitter is a jet-like structure, we performed detailed numerical calculations of the energy spectrum and lightcurves accounting for the acceleration efficiency, the location of the accelerator, the speed of the emitting flow, the inclination angle of the system, as well as specific features related to anisotropic inverse Compton scattering and pair production. We conclude that the accelerator should not be deep inside the binary system unless we assume a very efficient acceleration rate. We show that within the IC scenario both the gamma-ray spectrum and flux are strongly orbital phase d...

  4. On the formation of TeV radiation in LS 5039

    E-Print Network [OSTI]

    Dmitry Khangulyan; Felix Aharonian; Valenti Bosch-Ramon

    2007-10-10

    The recent detections of TeV gamma-rays from compact binary systems show that relativistic outflows (jets or winds) are sites of effective acceleration of particles up to multi-TeV energies. In this paper, we discuss the conditions of acceleration and radiation of ultra-relativistic electrons in LS 5039, the gamma-ray emitting binary system for which the highest quality TeV data are available. Assuming that the gamma-ray emitter is a jet-like structure, we performed detailed numerical calculations of the energy spectrum and lightcurves accounting for the acceleration efficiency, the location of the accelerator, the speed of the emitting flow, the inclination angle of the system, as well as specific features related to anisotropic inverse Compton scattering and pair production. We conclude that the accelerator should not be deep inside the binary system unless we assume a very efficient acceleration rate. We show that within the IC scenario both the gamma-ray spectrum and flux are strongly orbital phase dependent. Formally, our model can reproduce, for specific sets of parameter values, the energy spectrum of gamma-rays reported by HESS for wide orbital phase intervals. However, the physical properties of the source can be constrained only by observations capable of providing detailed energy spectra for narrow orbital phase intervals ($\\Delta\\phi\\ll 0.1$).

  5. TeV Gamma-Ray Sources from a Survey of the Galactic Plane with Milagro

    E-Print Network [OSTI]

    A. A. Abdo; B. Allen; D. Berley; S. Casanova; C. Chen; D. G. Coyne; B. L. Dingus; R. W. Ellsworth; L. Fleysher; R. Fleysher; M. M. Gonzalez; J. A. Goodman; E. Hays; C. M. Hoffman; B. Hopper; P. H. Huntemeyer; B. E. Kolterman; C. P. Lansdell; J. T. Linnemann; J. E. McEnery; A. I. Mincer; P. Nemethy; D. Noyes; J. M. Ryan; P. M. Saz Parkinson; A. Shoup; G. Sinnis; A. J. Smith; G. W. Sullivan; V. Vasileiou; G. P. Walker; D. A. Williams; X. W. Xu; G. B. Yodh

    2007-05-04

    A survey of Galactic gamma-ray sources at a median energy of ~20 TeV has been performed using the Milagro Gamma Ray Observatory. Eight candidate sources of TeV emission are detected with pre-trials significance $>4.5\\sigma$ in the region of Galactic longitude $l\\in[30^\\circ,220^\\circ]$ and latitude $b\\in[-10^\\circ,10^\\circ]$. Four of these sources, including the Crab nebula and the recently published MGRO J2019+37, are observed with significances $>4\\sigma$ after accounting for the trials involved in searching the 3800 square degree region. All four of these sources are also coincident with EGRET sources. Two of the lower significance sources are coincident with EGRET sources and one of these sources is Geminga. The other two candidates are in the Cygnus region of the Galaxy. Several of the sources appear to be spatially extended. The fluxes of the sources at 20 TeV range from ~25% of the Crab flux to nearly as bright as the Crab.

  6. Milagro Observations of TeV Emission from Galactic Sources in the Fermi Bright Source List

    E-Print Network [OSTI]

    Abdo, A A; Aune, T; Berley, D; Chen, C; Christopher, G E; DeYoung, T; Dingus, B L; Ellsworth, R W; González, M M; Goodman, J A; Hays, E; Hoffman, C M; Huentemeyer, P H; Kolterman, B E; Linnemann, J T; McEnery, J E; Morgan, T; Mincer, A I; Némethy, P; Pretz, J; Ryan, J M; Parkinson, P M Saz; Shoup, A; Sinnis, G; Smith, A J; Vasileiou, V; Walker, G P; Williams, D A; Yodh, G B

    2009-01-01

    We present the result of a search of Milagro sky map for spatial correlations with sources from a subset of the recent Fermi Bright Source List (BSL). The BSL consists of the 205 most significant sources detected above 100 MeV by the Fermi Large Area Telescope. We select sources based on their categorization in the BSL, taking all confirmed or possible Galactic sources in the field of view of Milagro. Of the 34 Fermi sources selected, 14 are observed by Milagro at a significance of 3 standard deviations or more. We conduct this search with a new analysis which employs newly-optimized gamma-hadron separation and utilizes the full 8-year Milagro dataset. Milagro is sensitive to gamma rays above 1 TeV and these results extend the observation of these sources far above the Fermi energy band. With the new analysis and additional data, TeV emission is definitively observed associated with the Fermi pulsar J2229.0+6114, in the the Boomerang Pulsar Wind Nebula (PWN). Furthermore, an extended region of TeV emission is...

  7. TeV Gamma-Ray Sources from a Survey of the Galactic Plane with Milagro

    E-Print Network [OSTI]

    Abdo, A A; Berley, D; Casanova, S; Chen, C; Coyne, D G; Dingus, B L; Ellsworth, R W; Fleysher, L; Fleysher, R; González, M M; Goodman, J A; Hays, E; Hoffman, C M; Hopper, B; Huntemeyer, P H; Kolterman, B E; Lansdell, C P; Linnemann, J T; McEnery, J E; Mincer, A I; Noyes, D; Némethy, P; Parkinson, P M Saz; Ryan, J M; Shoup, A; Sinnis, G; Smith, A J; Sullivan, G W; Vasileiou, V; Walker, G P; Williams, D A; Xu, X W; Yodh, G B

    2007-01-01

    A survey of Galactic gamma-ray sources at a median energy of ~20 TeV has been performed using the Milagro Gamma Ray Observatory. Eight candidate sources of TeV emission are detected with pre-trials significance $>4.5\\sigma$ in the region of Galactic longitude $l\\in[30^\\circ,220^\\circ]$ and latitude $b\\in[-10^\\circ,10^\\circ]$. Four of these sources, including the Crab nebula and the recently published MGRO J2019+37, are observed with significances $>4\\sigma$ after accounting for the trials involved in searching the 3800 square degree region. All four of these sources are also coincident with EGRET sources. Two of the lower significance sources are coincident with EGRET sources and one of these sources is Geminga. The other two candidates are in the Cygnus region of the Galaxy. Several of the sources appear to be spatially extended. The fluxes of the sources at 20 TeV range from ~25% of the Crab flux to nearly as bright as the Crab.

  8. First Results of a Study of TeV Emission from GRBs in Milagrito

    E-Print Network [OSTI]

    McEnery, J E; Benbow, W; Berley, D; Chen, M L; Coyne, D G; Dingus, B L; Dorfan, D E; Ellsworth, R W; Evans, D; Falcone, A D; Fleysher, L; Fleysher, R; Gisler, G; Goodman, J A; Haines, T J; Hoffman, C M; Hugenberger, S; Kelley, L A; Leonor, I; McConnell, M; McCullough, J F; Miller, R S; Mincer, A I; Morales, M F; Némethy, P; Ryan, J M; Shen, B; Shoup, A L; Sinnis, C; Smith, A J; Sullivan, G W; Tümer, T O; Wang, K; Wascko, M O; Westerhoff, S; Williams, D A; Yang, T; Yodh, G B

    1999-01-01

    Milagrito, a detector sensitive to gamma-rays at TeV energies, monitored the northern sky during the period February 1997 through May 1998. With a large field of view and high duty cycle, this instrument was used to perform a search for TeV counterparts to gamma-ray bursts. Within the Milagrito field of view 54 gamma-ray bursts at keV energies were observed by the Burst And Transient Satellite Experiment (BATSE) aboard the Compton Gamma-Ray Observatory. This paper describes the results of a preliminary analysis to search for TeV emission correlated with BATSE detected bursts. Milagrito detected an excess of events coincident both spatially and temporally with GRB 970417a, with chance probability $2.8 \\times 10^{-5}$ within the BATSE error radius. No other significant correlations were detected. Since 54 bursts were examined the chance probability of observing an excess with this significance in any of these bursts is $1.5 \\times 10^{-3}$. The statistical aspects and physical implications of this result are di...

  9. First Results of a Study of TeV Emission from GRBs in Milagrito

    E-Print Network [OSTI]

    J. E. McEnery; R. Atkins; W. Benbow; D. Berley; M. L. Chen; D. G. Coyne; B. L. Dingus; D. E. Dorfan; R. W. Ellsworth; D. Evans; A. Falcone; L. Fleysher; R. Fleysher; G. Gisler; J. A. Goodman; T. J. Haines; C. M. Hoffman; S. Hugenberger; L. A. Kelley; I. Leonor; M. McConnell; J. F. McCullough; R. S. Miller; A. I. Mincer; M. F. Morales; P. Nemethy; J. M. Ryan; B. Shen; A. Shoup; C. Sinnis; A. J. Smith; G. W. Sullivan; T. Tumer; K. Wang; M. O. Wascko; S. Westerhoff; D. A. Williams; T. Yang; G. B. Yodh

    1999-10-29

    Milagrito, a detector sensitive to gamma-rays at TeV energies, monitored the northern sky during the period February 1997 through May 1998. With a large field of view and high duty cycle, this instrument was used to perform a search for TeV counterparts to gamma-ray bursts. Within the Milagrito field of view 54 gamma-ray bursts at keV energies were observed by the Burst And Transient Satellite Experiment (BATSE) aboard the Compton Gamma-Ray Observatory. This paper describes the results of a preliminary analysis to search for TeV emission correlated with BATSE detected bursts. Milagrito detected an excess of events coincident both spatially and temporally with GRB 970417a, with chance probability $2.8 \\times 10^{-5}$ within the BATSE error radius. No other significant correlations were detected. Since 54 bursts were examined the chance probability of observing an excess with this significance in any of these bursts is $1.5 \\times 10^{-3}$. The statistical aspects and physical implications of this result are discussed.

  10. Searching for Neutrinoless Double-Beta Decay of130Te with CUORE

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Artusa, D. R.; Avignone, F. T.; Azzolini, O.; Balata, M.; Banks, T. I.; Bari, G.; Beeman, J.; Bellini, F.; Bersani, A.; Biassoni, M.; et al

    2015-01-01

    Neutrinoless double-beta (0???) decay is a hypothesized lepton-number-violating process that offers the only known means of asserting the possible Majorana nature of neutrino mass. The Cryogenic Underground Observatory for Rare Events (CUORE) is an upcoming experiment designed to search for 0???decay of130Te using an array of 988 TeO2crystal bolometers operated at 10?mK. The detector will contain 206?kg of130Te and have an average energy resolution of 5?keV; the projected 0???decay half-life sensitivity after five years of livetime is 1.6?×?1026?y at 1?(9.5?×?1025?y at the 90% confidence level), which corresponds to an upper limit on the effective Majorana massmore »in the range 40–100?meV (50–130?meV). In this paper, we review the experimental techniques used in CUORE as well as its current status and anticipated physics reach.« less

  11. Resonant nature of intrinsic defect energy levels in PbTe revealed by infrared photoreflectance spectroscopy

    SciTech Connect (OSTI)

    Zhang, Bingpo; Cai, Chunfeng; Jin, Shuqiang; Ye, Zhenyu; Wu, Huizhen, E-mail: hzwu@zju.edu.cn [Department of Physics and State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, Zhejiang 310027 (China); Qi, Zhen [National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China)

    2014-07-14

    Step-scan Fourier-transform infrared photoreflectance and modulated photoluminescence spectroscopy were used to characterize the optical transitions of the epitaxial PbTe thin film grown by molecular beam epitaxy on BaF{sub 2} (111) substrate in the vicinity of energy gap of lead telluride at 77?K. It is found that the intrinsic defect energy levels in the electronic structure are of resonant nature. The Te-vacancy energy level is located above the conduction band minimum by 29.1?meV. Another defect (V{sub X}) energy level situated below valance band maximum by 18.1?meV is also revealed. Whether it is associated with the Pb vacancy is still not clear. It might also be related to the misfit dislocations stemming from the lattice mismatch between PbTe and BaF{sub 2} substrate. The experimental results support the theory prediction (N. J. Parada and G. W. Pratt, Jr., Phys. Rev. Lett. 22, 180 (1969), N. J. Parada, Phys. Rev. B 3, 2042 (1971)) and are consistent with the reported Hall experimental results (G. Bauer, H. Burkhard, H. Heinrich, and A. Lopez-Otero, J. Appl. Phys. 47, 1721 (1976)).

  12. TeV {gamma} rays and neutrinos from photodisintegration of nuclei in Cygnus OB2

    SciTech Connect (OSTI)

    Anchordoqui, Luis A. [Department of Physics, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin 53201 (United States); Beacom, John F. [CCAPP, Departments of Physics and Astronomy, Ohio State University, Columbus, Ohio 43210 (United States); Goldberg, Haim [Department of Physics, Northeastern University, Boston, Massachusetts 02115 (United States); Palomares-Ruiz, Sergio [Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235 (United States); Institute for Particle Physics Phenomenology, University of Durham, Durham DH1 3LE (United Kingdom); Weiler, Thomas J. [Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235 (United States)

    2007-03-15

    TeV {gamma}-rays may provide significant information about high energy astrophysical accelerators. Such {gamma}-rays can result from the photo-de-excitation of PeV nuclei after their parents have undergone photo-disintegration in an environment of ultraviolet photons. This process is proposed as a candidate explanation of the recently discovered HEGRA source at the edge of the Cygnus OB2 association. The Lyman-{alpha} background is provided by the rich O and B stellar environment. It is found that (1) the HEGRA flux can be obtained if there is efficient acceleration at the source of lower energy nuclei; (2) the requirement that the Lorentz-boosted ultraviolet photons can excite the giant dipole resonance implies a strong suppression of the {gamma}-ray spectrum compared to an E{sub {gamma}}{sup -2} behavior at energies < or approx. 1 TeV (some of these energies will be probed by the upcoming GLAST mission); (3) a TeV neutrino counterpart from neutron decay following helium photo-disintegration will be observed at IceCube only if a major proportion of the kinetic energy budget of the Cygnus OB2 association is expended in accelerating nuclei.

  13. Searching for Neutrinoless Double-Beta Decay of 130 Te with CUORE

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Artusa, D. R.; Avignone, F. T.; Azzolini, O.; Balata, M.; Banks, T. I.; Bari, G.; Beeman, J.; Bellini, F.; Bersani, A.; Biassoni, M.; et al

    2015-01-01

    Neutrinoless double-beta (0 ? ? ? ) decay is a hypothesized lepton-number-violating process that offers the only known means of asserting the possible Majorana nature of neutrino mass. The Cryogenic Underground Observatory for Rare Events (CUORE) is an upcoming experiment designed to search for 0 ? ? ? decay of 130 Te using an array of 988 TeO 2 crystal bolometers operated at 10?mK. The detector will contain 206?kg of 130 Te and have an average energy resolution of 5?keV; the projected 0 ? ? ? decay half-life sensitivity aftermore »five years of livetime is 1.6?×?10 26 ?y at 1 ? (9.5?×?10 25 ?y at the 90% confidence level), which corresponds to an upper limit on the effective Majorana mass in the range 40–100?meV (50–130?meV). In this paper, we review the experimental techniques used in CUORE as well as its current status and anticipated physics reach. « less

  14. Algorithmically scalable block preconditioner for fully implicit shallow water equations in CAM-SE

    SciTech Connect (OSTI)

    Lott, P Aaron [Lawrence Livermore National Laboratory (LLNL); Woodward, Carol [Lawrence Livermore National Laboratory (LLNL); Evans, Katherine J [ORNL

    2015-01-01

    Performing accurate and efficient numerical simulation of global atmospheric climate models is challenging due to the disparate length and time scales over which physical processes interact. Implicit solvers enable the physical system to be integrated with a time step commensurate with processes being studied. The dominant cost of an implicit time step is the ancillary linear system solves, so we have developed a preconditioner aimed at improving the efficiency of these linear system solves. Our preconditioner is based on an approximate block factorization of the linearized shallow-water equations and has been implemented within the spectral element dynamical core within the Community Atmospheric Model (CAM-SE). In this paper we discuss the development and scalability of the preconditioner for a suite of test cases with the implicit shallow-water solver within CAM-SE.

  15. Yrast studies of {sup 80,82}Se using deep-inelastic reactions

    SciTech Connect (OSTI)

    Jones, G. A.; Regan, P. H.; Podolyak, Zs.; Gelletly, W.; Langdown, S. D. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Yoshinaga, N. [Department of Physics, Saitama University, Saitama City 338-8570 (Japan); Higashiyama, K. [Department of Physics, Chiba Institute of Technology, Narashino, Chiba 275-0023 (Japan); De Angelis, G.; Gadea, A.; Axiotis, M.; Kroell, Th.; Marginean, N.; Martinez, T.; Napoli, D. R.; Tonev, D. [Istituto Nazionale di Fisica Nucleare (INFN), Laboratori Nazionali di Legnaro (Italy); Zhang, Y. H. [Institute of Modern Physics, CAS, Lanzhou (China); Ur, C. A.; Bazzacco, D.; Farnea, E.; Lenzi, S. [INFN Sezione di Padova (Italy)] (and others)

    2007-11-15

    We report the results of an experiment in which we studied the near-yrast states in selenium isotopes approaching N=50 following their population in multinucleon transfer reactions between a {sup 82}Se beam and a {sup 192}Os target. The level schemes for {sup 80,82}Se derived from the current work are compared with restricted-basis shell-model calculations and pair-truncated shell-model calculations. These provide a good description of the yrast sequences in these nuclei using a basis space limited to excitations in the {nu}(p{sub (3/2)},p{sub (1/2)},g{sub (9/2)}) and {pi}(f{sub (5/2)},p{sub (3/2)},p{sub (1/2)}) orbitals.

  16. CdS/PbSe heterojunction for high temperature mid-infrared photovoltaic detector applications

    SciTech Connect (OSTI)

    Weng, Binbin, E-mail: binbinweng@ou.edu, E-mail: shi@ou.edu; Qiu, Jijun; Zhao, Lihua; Chang, Caleb [The School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States); Shi, Zhisheng, E-mail: binbinweng@ou.edu, E-mail: shi@ou.edu [The School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States); Nanolight, Inc., Norman, Oklahoma 73069 (United States)

    2014-03-24

    n-CdS/p-PbSe heterojunction is investigated. A thin CdS film is deposited by chemical bath deposition on top of epitaxial PbSe film by molecular beam epitaxy on Silicon. Current-voltage measurements demonstrate very good junction characteristics with rectifying ratio of ?178 and ideality factor of 1.79 at 300?K. Detectors made with such structure exhibit mid-infrared spectral photoresponse at room temperature. The peak responsivity R{sub ?} and specific detectivity D{sup *} are 0.055?A/W and 5.482?×?10{sup 8}?cm·Hz{sup 1/2}/W at ??=?4.7??m under zero-bias photovoltaic mode. Temperature-dependent photoresponse measurements show abnormal intensity variation below ?200?K. Possible reasons for this phenomenon are also discussed.

  17. Magnetism in La?O?(Fe??xMnx)?Se? tuned by Fe/Mn ratio

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lei, Hechang; Bozin, Emil S.; Llobet, A.; Ivanovski, V.; Koteski, V.; Belosevic-Cavor, J.; Cekic, B.; Petrovic, C.

    2012-09-01

    We report the evolution of structural and magnetic properties in La?O?(Fe??xMnx)?Se?. Heat capacity and bulk magnetization indicate an increased ferromagnetic component of the long-range magnetic order and possible increased degree of frustration. Atomic disorder on Fe(Mn) sites suppresses the temperature of the long-range order whereas intermediate alloys show a rich magnetic phase diagram.

  18. Statistical Mechanics of Disordered Systems, SoSe 2005 Timo Aspelmeier, Alexander K. Hartmann, Universitat Gottingen

    E-Print Network [OSTI]

    Hartmann, Alexander K.

    Statistical Mechanics of Disordered Systems, SoSe 2005 Timo Aspelmeier, Alexander K. Hartmann reserach! Statistics: most people leave our offices alive. Homepage: http://www.theorie.physik.uni-goe.de/~hartmann://www.theorie.physik.uni-goe.de/~aspel Alexander K. Hartmann Office A4.108 Phone +49-(0)551 39 5995 hartmann@physik.uni-goettingen.de http://www.theorie.physik.uni-goe.de/~hartmann

  19. Search for New Phenomena in Dijet Angular Distributions in Proton-Proton Collisions at s = 8 TeV Measured with the ATLAS Detector

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Aben, R.; Abolins, M.; AbouZeid, O. S.; Abramowicz, H.; Abreu, H.; Abreu, R.; et al

    2015-06-04

    A search for new phenomena in LHC proton-proton collisions at a center-of-mass energy of ?s=8 TeV was performed with the ATLAS detector using an integrated luminosity of 17.3 fb?¹. The angular distributions are studied in events with at least two jets; the highest dijet mass observed is 5.5 TeV. All angular distributions are consistent with the predictions of the standard model. In a benchmark model of quark contact interactions, a compositeness scale below 8.1 TeV in a destructive interference scenario and 12.0 TeV in a constructive interference scenario is excluded at 95% C.L.; median expected limits are 8.9 TeV formore »the destructive interference scenario and 14.1 TeV for the constructive interference scenario.« less

  20. Material and detector properties of cadmium manganese telluride (Cd1-xMnxTe) crystals grown by the modified floating-zone method

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hossain, A.; Gu, G. D.; Bolotnikov, A. E.; Camarda, G. S.; Cui, Y.; Roy, U. N.; Yang, G.; Liu, T.; Zhong, R.; Schneelock, J.; et al

    2014-12-24

    We demonstrated the material- and radiation-detection properties of cadmium manganese telluride (Cd1-xMnxTe; x=0.06), a wide-band-gap semiconductor crystal grown by the modified floating-zone method. We investigated the presence of various bulk defects, such as Te inclusions, twins, and dislocations of several as-grown indium-doped Cd1-xMnxTe crystals using different techniques, viz., IR transmission microscopy, and chemical etching. We then fabricated four planar detectors from selected CdMnTe crystals, characterized their electrical properties, and tested their performance as room-temperature X- and gamma-ray detectors. Thus, our experimental results show that CMT crystals grown by the modified floating zone method apparently are free from Te inclusions. However,more »we still need to optimize our growth parameters to attain high-resistivity, large-volume single-crystal CdMnTe.« less