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Sample records for ge lighting ge

  1. GE Lighting Solutions: Order (2013-SE-4901)

    Broader source: Energy.gov [DOE]

    DOE ordered General Electric Lighting Solutions, LLC to pay a $5,360 civil penalty after finding GE Lighting Solutions had manufactured and distributed in commerce in the U.S. 30 units of basic model DR4-RTFB-23B and 177 units (of which 85 units remain in inventory) of basic model DR4-RTFB-77A-002, noncompliant traffic signal modules.

  2. CTu2J.1.pdf CLEO Technical Digest OSA 2012 Light Emission in Ge Quantum Wells

    E-Print Network [OSTI]

    Miller, David A. B.

    CTu2J.1.pdf CLEO Technical Digest © OSA 2012 Light Emission in Ge Quantum Wells Edward T. Fei1 Engineering, Stanford University, Stanford, CA 94305, USA edfei@stanford.edu Abstract: We present the Ge/SiGe and electroluminescence show enhanced optical properties over bulk Ge. Further optical enhancement is observed in disk

  3. Advanced Lighting Technologies | GE Global Research

    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 of NaturalDukeWakefieldSulfateSciTechtail.Theory of raregovAboutRecovery Act RecoveryTechnologies |Appliances & Lighting

  4. Diffusion in SiGe and Ge

    E-Print Network [OSTI]

    Liao, Christopher Yuan Ting

    2010-01-01

    Claeys, et al. , "Si versus Ge for future microelectronics,"in Selectively Doped Si/Si x Ge 1-x Superlattices," PhysicalA. Fitzgerald, et al. , "Relaxed Ge x Si 1-x structures for

  5. Project planning workshop 6-GeV synchrotron light source: Volume 2

    SciTech Connect (OSTI)

    Not Available

    1986-01-01

    A series of work sheets, graphs, and printouts are given which detail the work breakdown structure, cost, and manpower requirements for the 6 GeV Synchrotron Light Source. (LEW)

  6. Impact of Minority Carrier Lifetime on the Performance of Strained Ge Light Sources

    E-Print Network [OSTI]

    Sukhdeo, David S; Birendra,; Dutt,; Nam, Donguk

    2015-01-01

    We theoretically investigate the impact of the defect-limited carrier lifetime on the performance of germanium (Ge) light sources, specifically LEDs and lasers. For Ge LEDs, we show that improving the material quality can offer even greater enhancements than techniques such as tensile strain, the leading approach for enhancing Ge light emission. Even for Ge that is so heavily strained that it becomes a direct bandgap semiconductor, the ~1 ns defect-limited carrier lifetime of typical epitaxial Ge limits the LED internal quantum efficiency to less than 10%. In contrast, if the epitaxial Ge carrier lifetime can be increased to its bulk value, internal quantum efficiencies exceeding 90% become possible. For Ge lasers, we show that the defect-limited lifetime becomes increasing important as tensile strain is introduced, and that this defect-limited lifetime must be improved if the full benefits of strain are to be realized. We conversely show that improving the material quality supersedes much of the utility of n...

  7. Room temperature 1.6 m electroluminescence from Ge light emitting diode on Si substrate

    E-Print Network [OSTI]

    Vuckovic, Jelena

    Room temperature 1.6 µm electroluminescence from Ge light emitting diode on Si substrate Szu n+/p light emitting diode on a Si substrate. Unlike normal electrically pumped devices, this device.4670) Optical materials; (230.3670) Light-emitting diodes. References and links 1. L. C. Kimerling, "Silicon

  8. GE's Digital Marketplace to Revolutionize Manufacturing | GE...

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

    an open online space for companies to collaborate and transform how they design and manufacture their products in the future NISKAYUNA, NY, June 2, 2015 - GE (NYSE:GE), a leading...

  9. Light Stops, Light Staus and the 125 GeV Higgs

    SciTech Connect (OSTI)

    Carena, Marcela; Gori, Stefania; Shah, Nausheen R.; Wagner, Carlos E.M.; Wang, Lian-Tao

    2013-08-01

    The ATLAS and CMS experiments have recently announced the discovery of a Higgs-like resonance with mass close to 125 GeV. Overall, the data is consistent with a Standard Model (SM)-like Higgs boson. Such a particle may arise in the minimal supersymmetric extension of the SM with average stop masses of the order of the TeV scale and a sizable stop mixing parameter. In this article we discuss properties of the SM-like Higgs production and decay rates induced by the possible presence of light staus and light stops. Light staus can affect the decay rate of the Higgs into di-photons and, in the case of sizable left-right mixing, induce an enhancement in this production channel up to $\\sim$ 50% of the Standard Model rate. Light stops may induce sizable modifications of the Higgs gluon fusion production rate and correlated modifications to the Higgs diphoton decay. Departures from SM values of the bottom-quark and tau-lepton couplings to the Higgs can be obtained due to Higgs mixing effects triggered by light third generation scalar superpartners. We describe the phenomenological implications of light staus on searches for light stops and non-standard Higgs bosons. Finally, we discuss the current status of the search for light staus produced in association with sneutrinos, in final states containing a $W$ gauge boson and a pair of $\\tau$s.

  10. Kinetics of visible light photo-oxidation of Ge nanocrystals:Theory and in situ measurement

    SciTech Connect (OSTI)

    Sharp, I.D.; Xu, Q.; Yuan, C.W.; Beeman, J.W.; Ager III, J.W.; Chrzan, D.C.; Haller, E.E.

    2006-11-14

    Photo-oxidation of Ge nanocrystals illuminated with visible laser light under ambient conditions was investigated. The photo-oxidation kinetics were monitored by in situ measurement of the crystalline Ge volume fraction by Raman spectroscopy. The effects of laser power and energy on the extent of oxidation were measured using both in situ and ex situ Raman scattering techniques. A mechanistic model in which the tunneling of photo-excited carriers to the oxide surface for electron activated molecular oxygen dissociation is proposed. This quantitative model successfully describes all experimental photo-oxidation observations using physical parameters.

  11. GE Lighting Solutions: Proposed Penalty (2013-SE-4901)

    Broader source: Energy.gov [DOE]

    DOE alleged in a Notice of Proposed Civil Penalty that General Electric Lighting Solutions manufactured and distributed noncompliant traffic signal modules in the U.S.

  12. GE Lighting Solutions: Noncompliance Determination (2013-SE-4901)

    Broader source: Energy.gov [DOE]

    DOE issued a Notice of Noncompliance Determination to General Electric Lighting Solutions finding that various models of traffic signal modules do not comport with the energy conservation standards.

  13. CHEM 114 GE 124 MATH 110 GE 110 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120

    E-Print Network [OSTI]

    Saskatchewan, University of

    2006-07 CHEM 114 GE 124 MATH 110 GE 110 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120 GE 210 MATH 223CE 212 CMPT 116 Hum/SocSci Jr. GEOE 218 CE 225 MATH 224GE 213# GE 348# CE 295 English 11x# CE 315 CE 311

  14. CHEM 114 GE 124 MATH 110 GE 110 COMM 102 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120

    E-Print Network [OSTI]

    Saskatchewan, University of

    CHEM 114 GE 124 MATH 110 GE 110 COMM 102 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120 ME 227 GE 213# MATH 223 EE 201ME 214 CMPT 116 ME 215 GE 226 MATH 224 Hum/SocSci@# ME 251 ME 229 ME 318 ME 335 ME 313

  15. GE ?????????????????4G?????...

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

    A die containing 400 ohmic MEMS switches, as viewed under a microscope, atop a U.S. dime. This device, made with GE's...

  16. CHEM 114 GE 124 MATH 110 COMM 102GE 110 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120

    E-Print Network [OSTI]

    Saskatchewan, University of

    CHEM 114 GE 124 MATH 110 COMM 102GE 110 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120 CMPT 116CHEM 250# MATH 223 EE 201 GE 213 Grp. A elective*CHE 223 Hum/SocSci Jr. MATH 224 English 11x CHE 220CHE 210 CHE

  17. CHEM 114 GE 124 MATH 110 COMM 102GE 110 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120

    E-Print Network [OSTI]

    Saskatchewan, University of

    CHEM 114 GE 124 MATH 110 COMM 102GE 110 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120 CMPT 116CHEM 250# MATH 223 EE 201 GE 213 Grp. A elective*CHE 223 HSS@# MATH 224 English 11x CHE 220CHE 210 CHE 323 CHE

  18. A Spin-Light Polarimeter for Multi-GeV Longitudinally Polarized Electron Beams

    SciTech Connect (OSTI)

    Mohanmurthy, Prajwal [Mississippi State University, Starkville, MS (United States); Dutta, Dipangkar [Mississippi State University, Starkville, MS (United States) and Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    2014-02-01

    The physics program at the upgraded Jefferson Lab (JLab) and the physics program envisioned for the proposed electron-ion collider (EIC) include large efforts to search for interactions beyond the Standard Model (SM) using parity violation in electroweak interactions. These experiments require precision electron polarimetry with an uncertainty of < 0.5 %. The spin dependent Synchrotron radiation, called "spin-light," can be used to monitor the electron beam polarization. In this article we develop a conceptual design for a "spin-light" polarimeter that can be used at a high intensity, multi-GeV electron accelerator. We have also built a Geant4 based simulation for a prototype device and report some of the results from these simulations.

  19. GE Research and Development | GE Global Research

    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 (Journal About DOE ButtonFSO HomefeatureGE

  20. GE Global Research Leadership | GE Global Research

    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 Room NewsInformation Current HABFESOpportunities Nuclear Physics (NP)about aMunich, GermanyAbout GE

  1. GE Researcher Discusses Leadership | GE Global Research

    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 Room NewsInformation Current HABFESOpportunities Nuclear Physics (NP)aboutRio de Janeiro,theIsGE

  2. Thermoelectric properties of nanoporous Ge

    E-Print Network [OSTI]

    Lee, Joo-Hyoung

    We computed thermoelectric properties of nanoporous Ge (np-Ge) with aligned pores along the [001] direction through a combined classical molecular dynamics and first-principles electronic structure approach. A significant ...

  3. GE Anna Heijbel / The Storm

    E-Print Network [OSTI]

    Tian, Weidong

    1 / GE Anna Heijbel / The Storm® Confocal Optics 50, 100, 200 µm 5 IQTL · ·DNA ·DNA Gels, blots, tissue sections (not in situ), radio-TLC & X-Ray diffraction #12;2 / GE Anna Heijbel / Phosphor µm 1010 43 x 35 cm43 x 35 cm Scanning Technology #12;3 / GE Anna Heijbel / Confocal Optics PMTPMT

  4. Light nuclides produced in the proton-induced spallation of {sup 238}U at 1 GeV

    SciTech Connect (OSTI)

    Ricciardi, M.V.; Armbruster, P.; Enqvist, T.; Kelic, A.; Rejmund, F.; Schmidt, K.-H.; Yordanov, O.; Benlliure, J.; Pereira, J.; Bernas, M.; Mustapha, B.; Stephan, C.; Tassan-Got, L.

    2006-01-15

    The production of light and intermediate-mass nuclides formed in the reaction {sup 1}H+{sup 238}U at 1 GeV was measured at the Fragment Separator at GSI, Darmstadt. The experiment was performed in inverse kinematics, by shooting a 1 A GeV {sup 238}U beam on a thin liquid-hydrogen target. A total of 254 isotopes of all elements in the range 7{<=}Z{<=}37 were unambiguously identified, and the velocity distributions of the produced nuclides were determined with high precision. The results show that the nuclides are produced in a very asymmetric binary decay of heavy nuclei originating from the spallation of uranium. All the features of the produced nuclides merge with the characteristics of the fission products as their mass increases.

  5. Light Nuclides Produced in the Proton-Induced Spallation of 238U at 1 GeV

    E-Print Network [OSTI]

    M. V. Ricciardi; P. Armbruster; J. Benlliure; M. Bernas; A. Boudard; S. Czajkowski; T. Enqvist; A. Kelic; S. Leray; R. Legrain; B. Mustapha; J. Pereira; F. Rejmund; K. -H. Schmidt; C. Stephan; L. Tassan-Got; C. Volant; O. Yordanov

    2005-08-24

    The production of light and intermediate-mass nuclides formed in the reaction 1H+238U at 1 GeV was measured at the Fragment Separator (FRS) at GSI, Darmstadt. The experiment was performed in inverse kinematics, shooting a 1 A GeV 238U beam on a thin liquid-hydrogen target. 254 isotopes of all elements in the range from Z=7 to Z=37 were unambiguously identified, and the velocity distributions of the produced nuclides were determined with high precision. The results show that the nuclides are produced in a very asymmetric binary decay of heavy nuclei originating from the spallation of uranium. All the features of the produced nuclides merge with the characteristics of the fission products as their mass increases.

  6. Characteristics of Sn segregation in Ge/GeSn heterostructures

    SciTech Connect (OSTI)

    Li, H.; Chang, C.; Chen, T. P.; Cheng, H. H., E-mail: hhcheng@ntu.edu.tw [Center for Condensed Matter Sciences and Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Shi, Z. W.; Chen, H. [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2014-10-13

    We report an investigation of Sn segregation in Ge/GeSn heterostructures occurred during the growth by molecular beam epitaxy. The measured Sn profile in the Ge layer shows that: (a) the Sn concentration decreases rapidly near the Ge/GeSn interface, and (b) when moving away from the interface, the Sn concentration reduced with a much slower rate. The 1/e decay lengths of the present system are much longer than those of the conventional group IV system of Ge segregation in the Si overlayer because of the smaller kinetic potential as modeled by a self-limited two-state exchange scheme. The demonstration of the Sn segregation shows the material characteristics of the heterostructure, which are needed for the investigation of its optical properties.

  7. CTu2J.4.pdf CLEO Technical Digest OSA 2012 Selective-Area Growth of Ge and Ge/SiGe Quantum Wells

    E-Print Network [OSTI]

    Miller, David A. B.

    CTu2J.4.pdf CLEO Technical Digest © OSA 2012 Selective-Area Growth of Ge and Ge/SiGe Quantum Wells process for growing high-quality bulk Ge and Ge/SiGe quantum wells in selected areas of 3 µm thick silicon. Introduction and motivation Ge and especially Ge/SiGe quantum wells exhibit strong electroabsorption (Franz

  8. GE Partners on Microgrid Project | GE Global Research

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

    control platform which can be used to host intelligent grid management software for microgrids. A typical GE control platform which can be used to host intelligent grid management...

  9. GE Develops High Water Recovery Technology in China | GE Global...

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

    purification industry SHANGHAI, September. 17, 2015 - A team of scientists led by the Coating and Membrane Technology Laboratory at GE's China Technology Center have successfully...

  10. Light harvesting with Ge quantum dots embedded in SiO{sub 2} or Si{sub 3}N{sub 4}

    SciTech Connect (OSTI)

    Cosentino, Salvatore Raciti, Rosario; Simone, Francesca; Crupi, Isodiana; Terrasi, Antonio; Mirabella, Salvo; Sungur Ozen, Emel; Aydinli, Atilla; Mio, Antonio M.; Nicotra, Giuseppe; Turan, Rasit

    2014-01-28

    Germanium quantum dots (QDs) embedded in SiO{sub 2} or in Si{sub 3}N{sub 4} have been studied for light harvesting purposes. SiGeO or SiGeN thin films, produced by plasma enhanced chemical vapor deposition, have been annealed up to 850?°C to induce Ge QD precipitation in Si based matrices. By varying the Ge content, the QD diameter can be tuned in the 3–9?nm range in the SiO{sub 2} matrix, or in the 1–2?nm range in the Si{sub 3}N{sub 4} matrix, as measured by transmission electron microscopy. Thus, Si{sub 3}N{sub 4} matrix hosts Ge QDs at higher density and more closely spaced than SiO{sub 2} matrix. Raman spectroscopy revealed a higher threshold for amorphous-to-crystalline transition for Ge QDs embedded in Si{sub 3}N{sub 4} matrix in comparison with those in the SiO{sub 2} host. Light absorption by Ge QDs is shown to be more effective in Si{sub 3}N{sub 4} matrix, due to the optical bandgap (0.9–1.6?eV) being lower than in SiO{sub 2} matrix (1.2–2.2?eV). Significant photoresponse with a large measured internal quantum efficiency has been observed for Ge QDs in Si{sub 3}N{sub 4} matrix when they are used as a sensitive layer in a photodetector device. These data will be presented and discussed, opening new routes for application of Ge QDs in light harvesting devices.

  11. GE Healthcare Product Guide 2007

    E-Print Network [OSTI]

    Lebendiker, Mario

    GE Healthcare BioProcess Product Guide 2007 #12;How to contact us Europe www.gehealthcare.com/bioprocess or by phone (T), fax (F), and Email Austria T: +43 1 57 606 1613 F: +43 1 57 606 1614 Email: cust.orderde@ge.com Belgium T: 0800 73890 F: 02 416 8206 Email: order.bnl@ge.com Central and East Europe (Austria) T: +43 1

  12. Magnetic Refrigeration | GE Global Research

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

    and it will become hotter. Move it away (demagnetization) and the food cools down. GE researchers predict the cooling refrigerators could reduce energy consumption by 20%, in...

  13. Flexible Energy | GE Global Research

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

    (Opens in new window) Flexible Fuel Solutions Offer Efficient, Reliable Energy The world of power generation is evolving at lightning speed. GE is focused on staying one step...

  14. GE Energy Management Ancillary Services

    E-Print Network [OSTI]

    GE Energy Management Ancillary Services Definitions and Capability Study Part 2, Tasks 3-4, Final Online Wind Plants & Frequency Responsive Load Reserves

  15. The 750 GeV Diphoton Excess as a First Light on Supersymmetry Breaking

    E-Print Network [OSTI]

    J. A. Casas; J. R. Espinosa; J. M. Moreno

    2015-12-24

    One of the most exciting explanations advanced for the recent diphoton excess found by ATLAS and CMS is in terms of sgoldstino decays: a signal of low-energy supersymmetry-breaking scenarios. The sgoldstino, a scalar, couples directly to gluons and photons, with strength related to gaugino masses, that can be of the right magnitude to explain the excess. However, fitting the suggested resonance width, Gamma ~ 45 GeV, is not so easy. In this paper we explore efficient possibilities to enhance the sgoldstino width, via the decay into two Higgses, two Higgsinos and through mixing between the sgoldstino and the Higgs boson. In addition, we present an alternative and more efficient mechanism to generate a mass splitting between the scalar and pseudoscalar components of the sgoldstino, which has been suggested as an interesting alternative explanation to the apparent width of the resonance.

  16. Phenomenology of ``inos'' in the Light Gaugino Scenario and Possible Evidence for a $\\sim 53$ GeV Chargino

    E-Print Network [OSTI]

    Glennys R. Farrar

    1996-12-13

    The tree-level-massless gaugino scenario predicts that the lighter chargino mass is less than m_W and that gluino and lightest neutralino masses are $\\lsi 1$ GeV. In this case the dominant decay mode of charginos and non-LSP neutralinos is generically to three jets. The excess of "4j" events with total invariant mass $\\sim 105$ GeV observed in LEP running at 130-136 GeV is noted to be consistent with pair production of $\\sim 53$ GeV charginos. Data at 161 and 172 GeV from Fall, 1996, cannot conclusively test this hypothesis (because cuts to eliminate $W^+W^-$ background reduce the efficiency significantly) but is suggestive that the signal persists.

  17. Low-voltage broad-band electroabsorption from thin Ge/SiGe

    E-Print Network [OSTI]

    Miller, David A. B.

    Low-voltage broad-band electroabsorption from thin Ge/SiGe quantum wells epitaxially grown than 5 dB over the entire telecommunication S- and C-bands with only 1V drive using a new Ge/SiGe QW epitaxy design approach; further, this is demonstrated with the thinnest Ge/SiGe epitaxy to date, using

  18. CHEM 114 GE 124 MATH 110 COMM 102 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120

    E-Print Network [OSTI]

    Saskatchewan, University of

    GE 449# GE 110 Geological Engineering CE 271 GEOE 378 4TH YEAR 3RD YEAR 2ND YEAR 1ST YEAR or PHYS 128

  19. Miniaturized Turbine Offers Desalination Solution | GE Global...

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

    salt from ice New solution draws from the GE Store, integrating GE's experience with steam turbine, oil & gas compressors, 3D printing and water processing NISKAYUNA, NY,...

  20. Energy Frontier Research Center | GE Global Research

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

    include GE Global Research, Yale University-Crabtree Group, Yale University-Batista Group, Stanford University and Lawrence Berkeley National Laboratory. GE Global...

  1. Light NMSSM Neutralino Dark Matter in the Wake of CDMS II and a 126 GeV Higgs

    E-Print Network [OSTI]

    Kozaczuk, Jonathan

    2013-01-01

    Recent results from the Cryogenic Dark Matter Search (CDMS) experiment have renewed interest in light dark matter with a large spin-independent neutralino-nucleon scattering cross-section. Here, we examine the regions of the NMSSM capable of producing a light neutralino with a large direct detection cross-section, with scattering mediated by a light singlet-like scalar, and a 126 GeV Higgs consistent with the LHC results. We focus on two different scenarios for annihilation in the early universe, namely annihilation mediated by (1) a light scalar or by (2) a light pseudoscalar. We find that there exists viable parameter space in which a very light CP-even Higgs boson mediates both the neutralino-nucleon spin-independent elastic scattering and the neutralino pair-annihilation in the early universe. These regions can feature significant tree-level contributions to the SM-like Higgs mass and hence not require very heavy or highly-mixed stops. The strongest constraints in this case come from the decays of the SM-...

  2. A tale of tails. Dark matter interpretations of the Fermi GeV excess in light of background model systematics

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

    Calore, Francesca; Cholis, Ilias; McCabe, Christopher; Weniger, Christoph

    2015-03-10

    Several groups have identified an extended excess of gamma rays over the modeled foreground and background emissions towards the Galactic center (GC) based on observations with the Fermi Large Area Telescope. This excess emission is compatible in morphology and spectrum with a telltale sign from dark matter (DM) annihilation. Here, we present a critical reassessment of DM interpretations of the GC signal in light of the foreground and background uncertainties that some of us recently outlaid in Calore et al. (2014). We find that a much larger number of DM models fits the gamma-ray data than previously noted. In particular:more »(1) In the case of DM annihilation into b¯b, we find that even large DM masses up to m??74 GeV are allowed at p-value >0.05. (2) Surprisingly, annihilation into nonrelativistic hh gives a good fit to the data. (3) The inverse Compton emission from ?+?– with m? ~ 60–70 GeV can also account for the excess at higher latitudes, |b|>2°, both in its spectrum and morphology. We also present novel constraints on a large number of mixed annihilation channels, including cascade annihilation involving hidden sector mediators. In conclusion, we show that the current limits from dwarf spheroidal observations are not in tension with a DM interpretation when uncertainties on the DM halo profile are accounted for.« less

  3. Edison Summit Brings GE Leaders Together | GE Global Research

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

    We are ONE Edison Aisha Yousuf 2014.03.21 "We are ONE Edison" was the theme of the first GE Global Edison Summit held February 16-18, 2014 at Coronado Springs Resort in Orlando,...

  4. GE Researcher Explores Science Behind Movie Chappie | GE Global...

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

    When Will We Have Robot Best Friends? A GE Researcher Explores the Science Behind Movie Magic Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new...

  5. CHEM 114 GE 124 MATH 110 COMM 102 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120

    E-Print Network [OSTI]

    Saskatchewan, University of

    2005-2006 CHEM 114 GE 124 MATH 110 COMM 102 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120 GEOL 245 MATH 223 CE 328 CE 212 CE 225 CE 295GE 213# MATH 224 GEOL 224 GEOE 218 GEOL 258 BusSci/HSS# GEOE 315 GEOE

  6. CHEM 114 GE 124 MATH 110 COMM 102 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120

    E-Print Network [OSTI]

    Saskatchewan, University of

    2006-07 CHEM 114 GE 124 MATH 110 COMM 102 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120 GEOL 245 MATH 223 CE 328 CE 212 CE 225 CE 295GE 213# MATH 224 GEOL 224 GEOE 218 GEOL 258 Hum/SocSci Jr. GEOE 315

  7. Advanced Analytics | GE Global Research

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

    GE Predictivity(tm) Industrial Internet Solutions Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click to share (Opens in new window)...

  8. Recommended GE Curriculum for the BSEE Majors

    E-Print Network [OSTI]

    Ravikumar, B.

    Recommended GE Curriculum for the BSEE Majors Area Subjects Suggested GE Courses Courses Actual units GE Units A. Communication and Critical Thinking (9) A.2. Fund. of Communication ENGL 101 4 4 A.3, Theatre, Dance and Music and Film Select from the GE C.1 list in the SSU Catalog 3 3 C.2. Literature

  9. HSE 1 HSE 2 HSE 3 GE 1 GE 2 GE 3 Residual effects of Large Vessels in GE BOLD Differential Mapping of Ocular Dominance Columns

    E-Print Network [OSTI]

    HSE 1 HSE 2 HSE 3 GE 1 GE 2 GE 3 Residual effects of Large Vessels in GE BOLD Differential Mapping the contamination of non-specific large vessel signals. Animal studies have used non- conventional functional minimizing the contributions of extravascular BOLD signals around large vessels due to the refocusing pulse

  10. Strained Si, SiGe, and Ge on-insulator: review of wafer bonding fabrication techniques

    E-Print Network [OSTI]

    Strained Si, SiGe, and Ge on-insulator: review of wafer bonding fabrication techniques Gianni was arranged by Prof. C.K. Maiti Abstract Techniques for fabricating strained Si, SiGe, and Ge on-insulator include SIMOX, Ge condensation and wafer bonding. In this paper, a brief introduction of each method

  11. GeSi intermixing in Ge quantum dots on Si,,001... and Si,,111... F. Boscherinia)

    E-Print Network [OSTI]

    Ge­Si intermixing in Ge quantum dots on Si,,001... and Si,,111... F. Boscherinia) Laboratori December 1999 Exploiting Ge K-edge x-ray absorption spectroscopy we provide direct evidence of Si­Ge intermixing in self-organized strained and unstrained Ge quantum dots on Si, and provide a quantitative

  12. Nonlithographic epitaxial SnxGe1x dense nanowire arrays grown on Ge,,001...

    E-Print Network [OSTI]

    Atwater, Harry

    Nonlithographic epitaxial SnxGe1Àx dense nanowire arrays grown on Ge,,001... Regina Ragan-thick SnxGe1 x /Ge(001) epitaxial films with 0 x 0.085 by molecular-beam epitaxy. These films evolve during growth into a dense array of SnxGe1 x nanowires oriented along 001 , as confirmed by composition contrast

  13. Production of multistrange hadrons, light nuclei and hypertriton in central Au+Au collisions at $\\sqrt{s_{NN}}=$ 11.5 and 200 GeV

    E-Print Network [OSTI]

    Shah, N; Chen, J H; Zhang, and S

    2015-01-01

    The production of dibaryons, light nuclei and hypertriton in the most central Au+Au collisions at $\\sqrt{s_{NN}}=$ 11.5 and 200 GeV are investigated by using a naive coalescence model. The production of light nuclei is studied and found that the production rate reduces by a factor of 330 (1200) for each extra nucleon added to nuclei at $\\sqrt{s_{NN}}=$ 11.5 (200) GeV. The $p_{T}$ integrated yield of multistrange hadrons falls exponentially as strangeness quantum number increases. We further investigate strangeness population factor $S_{3}, S_{2}$ as a function of transverse momentum as well as $\\sqrt{s_{NN}}$. The baryon-strangeness correlation coefficient $C_{BS}$ is also investigated for $\\sqrt{s_{NN}}=$ 11.5 and 200 GeV. The calculations for $\\sqrt{s_{NN}}=$ 11.5 GeV presented here will stimulate interest to carry out these measurements during the phase-II of beam energy scan program at STAR experiment.

  14. 'Self-absorbed' GeV light curves of gamma-ray burst afterglows

    SciTech Connect (OSTI)

    Panaitescu, A.; Vestrand, W. T.; Wo?niak, P. [Space and Remote Sensing, MS B244, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2014-06-10

    We investigate the effect that the absorption of high-energy (above 100 MeV) photons produced in gamma-ray burst afterglow shocks has on the light curves and spectra of Fermi Large Area Telescope (LAT) afterglows. Afterglows produced by the interaction of a relativistic outflow with a wind-like medium peak when the blast wave deceleration sets in, and the afterglow spectrum could be hardening before that peak, as the optical thickness to pair formation is decreasing. In contrast, in afterglows produced in the interaction with a homogeneous medium, the optical thickness to pair formation should increase and yield a light curve peak when it reaches unity, followed by a fast light curve decay, accompanied by spectral softening. If energy is injected in the blast wave, then the accelerated increase of the optical thickness yields a convex afterglow light curve. Other features, such as a double-peak light curve or a broad hump, can arise from the evolution of the optical thickness to photon-photon absorption. Fast decays and convex light curves are seen in a few LAT afterglows, but the expected spectral softening is rarely seen in (and difficult to measure with) LAT observations. Furthermore, for the effects of photon-photon attenuation to shape the high-energy afterglow light curve without attenuating it too much, the ejecta initial Lorentz factor must be in a relatively narrow range (50-200), which reduces the chance of observing those effects.

  15. Effect of SiO2 coating in bolometric Ge light detectors for rare event searches

    E-Print Network [OSTI]

    J. W. Beeman; A. Gentils; A. Giuliani; M. Mancuso; G. Pessina; O. Plantevin; C. Rusconi

    2012-12-01

    In germanium-based light detectors for scintillating bolometers, a SiO$_2$ anti-reflective coating is often applied on the side of the germanium wafer exposed to light with the aim to improve its light collection efficiency. In this paper, we report about a measurement, performed in the temperature range 25-35 mK, of the light-collection increase obtained thanks to this method, which resulted to be of the order of 20%. The procedure followed has been carefully selected in order to minimize systematic effects. The employed light sources have the same spectral features (peaking at $\\sim 630$ nm wavelength) that will characterise future neutrinoless double beta decay experiments on the isotope $^{82}$Se and based on ZnSe crystals, such as LUCIFER. The coupling between source and light detector reproduces the configuration used in scintillating bolometers. The present measurement clarifies the role of SiO$_2$ coating and describes a method and a set-up that can be extended to the study of other types of coatings and luminescent materials.

  16. CHEM 114 GE 124 MATH 110 GE 110 COMM 102 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120

    E-Print Network [OSTI]

    Saskatchewan, University of

    ND YEAR 1ST YEAR 3RD YEAR # These courses can be taken in either term.*must meet specific Hum/SocSci@# Bus Sci/HSS#Design Elec.#* T.E.*# T.E.*#GE 449# ME 314 or PHYS 128 or GEOL 121 4TH YEAR 2

  17. GE Energy Management Ancillary Services

    E-Print Network [OSTI]

    GE Energy Management Ancillary Services Definitions and Capability Study Part 1, Tasks 1-2, FinalRose Michael O'Connor Sundar Venkataraman Revision 1 Date: 12/19/2012 #12;Ancillary Services Definitions.................................................................................................................... 7 3.1 Task 1: Identify and define ancillary services needed for integration of new generation

  18. PROBABILITY OF CORRECT SELECTION OF GAMMA VERSUS GE OR WEIBULL VERSUS GE BASED ON

    E-Print Network [OSTI]

    Kundu, Debasis

    PROBABILITY OF CORRECT SELECTION OF GAMMA VERSUS GE OR WEIBULL VERSUS GE BASED ON LIKELIHOOD RATIO proposes the use of likelihood ratio statistic in choosing between gamma and GE models or between Weibull and GE models. Probability of correct selec- tions are obtained using Monte Carlo simulations for various

  19. Moving | GE Global Research

    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 Administration wouldMass map shines light on77 PAGEMissionStressMove data fromMoving We're always working

  20. Understanding and engineering of NiGe/Ge junction formed by phosphorus ion implantation after germanidation

    SciTech Connect (OSTI)

    Oka, Hiroshi, E-mail: oka@asf.mls.eng.osaka-u.ac.jp; Minoura, Yuya; Hosoi, Takuji; Shimura, Takayoshi; Watanabe, Heiji [Department of Material and Life Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2014-08-11

    Modulation of the effective electron Schottky barrier height (eSBH) of NiGe/Ge contacts induced by phosphorus ion implantation after germanide formation was investigated by considering local inhomogeneity in the eSBH. Systematic studies of NiGe/Ge contact devices having various germanide thicknesses and ion implantation areas indicated the threshold dopant concentration at the NiGe/Ge interface required for eSBH modulation and negligible dopant diffusion even at NiGe/Ge interface during drive-in annealing, leading to variation in the eSBH between the bottom and sidewall portions of the NiGe regions. Consequently, this method makes it possible to design source/drain contacts with low-resistivity Ohmic and ideal rectifying characteristics for future Ge-based transistors.

  1. CHEM 114 GE 124 MATH 110 COMM 102GE 110 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120

    E-Print Network [OSTI]

    Saskatchewan, University of

    Engineering * must meet specific requirements # These courses can be taken in either term. 2ND YEAR 3RD YEAR 4 431 Last editted Apr 4, 2006 ^offered in alternate years; take in either 3rd or 4th year CHEM 242TH YEAR 1ST YEAR CHE 422 CHE 232 HSS@# 2005-2006 or PHYS 128 or GEOL 121 or AB E 312 GE 300# CHE 332

  2. ME 227 CE 212 MATH 223 GE 210 CMPT 116 ABE 211CHE 210 GE 213# MATH 224

    E-Print Network [OSTI]

    Saskatchewan, University of

    GE 120 ME 227 CE 212 MATH 223 GE 210 CMPT 116 ABE 211CHE 210 GE 213# MATH 224 ABE 295 ABE 212 can be taken in either term. GE 124 MATH 110 MATH 124CHEM 115 PHYS 155 3RD YEAR GE 125 GE 110 COMM 102

  3. Purdue, GE Collaborate On Advanced Manufacturing | GE Global Research

    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 Administration wouldMass mapSpeedingProgramExemptionsProteinTotal natural gasPurchase, Delivery,Purdue, GE to

  4. About GE Global Research Center | GE Global Research

    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 of NaturalDukeWakefieldSulfateSciTechtail.Theory of raregovAboutRecovery Act Recovery ActARM OverviewAbout GE Global Research

  5. GE Scientists Experiment With Texas BBQ | GE Global Research

    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 Administration would likeUniverse (Journal Article)Forthcoming UpgradesArea:Benefits ofofStackOn thePower ofGE

  6. Photoconductivity of Si/Ge multilayer structures with Ge quantum dots pseudomorphic to the Si matrix

    SciTech Connect (OSTI)

    Talochkin, A. B., E-mail: tal@thermo.isp.nsc.ru; Chistokhin, I. B. [Russian Academy of Sciences, Rzhanov Institute of Semiconductor Physics, Siberian Branch (Russian Federation)

    2011-07-15

    Longitudinal photoconductivity spectra of Si/Ge multilayer structures with Ge quantum dots grown pseudomorphically to the Si matrix are studied. Lines of optical transitions between hole levels of quantum dots and Si electronic states are observed. This allowed us to construct a detailed energy-level diagram of electron-hole levels of the structure. It is shown that hole levels of pseudomorphic Ge quantum dots are well described by the simplest 'quantum box' model using actual sizes of Ge islands. The possibility of controlling the position of the long-wavelength photosensitivity edge by varying the growth parameters of Si/Ge structures with Ge quantum dots is determined.

  7. Chevron, GE form Technology Alliance

    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 OutreachProductswsicloudwsiclouddenDVA N C E D BGene NetworkNuclear SecurityChattanChemistry ofNanChevron, GE form

  8. Advanced Analytics | GE Global Research

    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 Room News Publications Traditional Knowledge KiosksAboutHelp & Reference Users AdvAncedGE

  9. GE Global Research in San Ramon, California

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

    Careers Leadership Programs What's new in San Ramon Ars Technica: Analyzing the Internet of Things GE Unveils High-Speed Network Infrastructure to Connect Machines, Data...

  10. MOSFET Channel Engineering using Strained Si, SiGe, and Ge Channels

    E-Print Network [OSTI]

    Fitzgerald, Eugene A.

    Biaxial tensile strained Si grown on SiGe virtual substrates will be incorporated into future generations of CMOS technology due to the lack of performance increase with scaling. Compressively strained Ge-rich alloys with ...

  11. Modeling of GE Appliances: Final Presentation

    SciTech Connect (OSTI)

    Fuller, Jason C.; Vyakaranam, Bharat; Leistritz, Sean M.; Parker, Graham B.

    2013-01-31

    This report is the final in a series of three reports funded by U.S. Department of Energy Office of Electricity Delivery and Energy Reliability (DOE-OE) in collaboration with GE Appliances’ through a Cooperative Research and Development Agreement (CRADA) to describe the potential of GE Appliances’ DR-enabled appliances to provide benefits to the utility grid.

  12. GE Turbine Parts www.edisonmachine.com

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    GE Turbine Parts www.edisonmachine.com New authentic GE and Westinghouse Turbine Parts Muscle cars vehicle: Has the code for a hydrogen car been cracked? World-first working eukaryotic cell mad from's smallest windmills to power cell phones 1/17/2014http://www.gizmag.com/worlds-smallest-windmill-energy

  13. Growth and characterization of isotopically enriched [sup 70]Ge and [sup 74]Ge single crystals

    SciTech Connect (OSTI)

    Itoh, K.

    1992-10-01

    Isotopically enriched [sup 70]Ge and [sup 74]Ge single crystals were successfully gown by a newly developed vertical Bridgman method. The system allows us to reliably grow high purity Ge single crystals of approximately 1 cm[sup 3] volume. To our knowledge, we have grown the first [sup 70]Ge single crystal. The electrically active chemical impurity concentration for both crystals was found to be [approximately]2 [times] cm[sup [minus]3] which is two order of magnitude better that of [sup 74]Ge crystals previously grown by two different groups. Isotopic enrichment of the [sup 70]Ge and the [sup 74]Ge crystals is 96.3% and 96.8%, respectively. The residual chemical impurities present in both crystals were identified as phosphorus, copper, aluminum, and indium. A wide variety of experiments which take advantage of the isotopic purity of our crystals are discussed.

  14. Growth and characterization of isotopically enriched {sup 70}Ge and {sup 74}Ge single crystals

    SciTech Connect (OSTI)

    Itoh, K.

    1992-10-01

    Isotopically enriched {sup 70}Ge and {sup 74}Ge single crystals were successfully gown by a newly developed vertical Bridgman method. The system allows us to reliably grow high purity Ge single crystals of approximately 1 cm{sup 3} volume. To our knowledge, we have grown the first {sup 70}Ge single crystal. The electrically active chemical impurity concentration for both crystals was found to be {approximately}2 {times} cm{sup {minus}3} which is two order of magnitude better that of {sup 74}Ge crystals previously grown by two different groups. Isotopic enrichment of the {sup 70}Ge and the {sup 74}Ge crystals is 96.3% and 96.8%, respectively. The residual chemical impurities present in both crystals were identified as phosphorus, copper, aluminum, and indium. A wide variety of experiments which take advantage of the isotopic purity of our crystals are discussed.

  15. Monolithic Ge-on-Si lasers for integrated photonics

    E-Print Network [OSTI]

    Liu, Jifeng

    We report room temperature Ge-on-Si lasers with direct gap emission at 1590-1610 nm. Modeling of Ge/Si double heterojunction structures, which is supported by experimental results of Ge/Si LEDs, indicates the feasibility ...

  16. Is there a risk from not using GE animals?

    E-Print Network [OSTI]

    Murray, James D.; Maga, Elizabeth A.

    2010-01-01

    Is there a risk from not using GE animals? James D. Murray •rst genetically engi- neered (GE) plants and animals forthe debate often focuses on GE as a technique that is used

  17. Xergy Ships First Breakthrough Water Heater Compressor to GE...

    Energy Savers [EERE]

    Xergy Ships First Breakthrough Water Heater Compressor to GE Xergy Ships First Breakthrough Water Heater Compressor to GE September 15, 2015 - 3:41pm Addthis Xergy Inc. and GE...

  18. Passionate Technologists Wanted at ASME Turbo Expo|GE Global...

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

    who want to learn more about GE and its global Research Centers. For this purpose, the Aero & Thermal Systems groups of GE Global Research and representatives from several GE...

  19. Ge-on-Si laser for silicon photonics

    E-Print Network [OSTI]

    Camacho-Aguilera, Rodolfo Ernesto

    2013-01-01

    Ge-on-Si devices are explored for photonic integration. Importance of Ge in photonics has grown and through techniques developed in our group we demonstrated low density of dislocations (<1x109cm-2) and point defects Ge ...

  20. Understanding of interface structures and reaction mechanisms induced by Ge or GeO diffusion in Al{sub 2}O{sub 3}/Ge structure

    SciTech Connect (OSTI)

    Shibayama, Shigehisa [Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan) [Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); JSPS, 5-3-1 Kojimachi, Chiyoda-ku, Tokyo 102-0083 (Japan); Kato, Kimihiko; Sakashita, Mitsuo; Takeuchi, Wakana; Taoka, Noriyuki; Nakatsuka, Osamu; Zaima, Shigeaki [Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan)] [Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan)

    2013-08-19

    The reaction mechanisms at Al{sub 2}O{sub 3}/Ge interfaces with thermal oxidation through the Al{sub 2}O{sub 3} layer have been investigated. X-ray photoelectron spectroscopy reveals that an Al{sub 6}Ge{sub 2}O{sub 13} layer is formed near the interface, and a GeO{sub 2} layer is formed on the Al{sub 2}O{sub 3} surface, suggesting Ge or GeO diffusion from the Ge surface. It is also clarified that the Al{sub 6}Ge{sub 2}O{sub 13} layer is formed by the different mechanism with a small activation energy of 0.2 eV, compared with the GeO{sub 2} formation limited by oxygen diffusion. Formation of Al-O-Ge bonds due to the AlGeO formation could lead appropriate interface structures with high interface qualities.

  1. Study of Pu consumption in Advanced Light Water Reactors. Evaluation of GE Advanced Boiling Water Reactor plants

    SciTech Connect (OSTI)

    Not Available

    1993-05-13

    Timely disposal of the weapons plutonium is of paramount importance to permanently safeguarding this material. GE`s 1300 MWe Advanced Boiling Water Reactor (ABWR) has been designed to utilize fill] core loading of mixed uranium-plutonium oxide fuel. Because of its large core size, a single ABWR reactor is capable of disposing 100 metric tons of plutonium within 15 years of project inception in the spiking mode. The same amount of material could be disposed of in 25 years after the start of the project as spent fuel, again using a single reactor, while operating at 75 percent capacity factor. In either case, the design permits reuse of the stored spent fuel assemblies for electrical energy generation for the remaining life of the plant for another 40 years. Up to 40 percent of the initial plutonium can also be completely destroyed using ABWRS, without reprocessing, either by utilizing six ABWRs over 25 years or by expanding the disposition time to 60 years, the design life of the plants and using two ABWRS. More complete destruction would require the development and testing of a plutonium-base fuel with a non-fertile matrix for an ABWR or use of an Advanced Liquid Metal Reactor (ALMR). The ABWR, in addition, is fully capable of meeting the tritium target production goals with already developed target technology.

  2. Enhancement of thermal stability and water resistance in yttrium-doped GeO{sub 2}/Ge gate stack

    SciTech Connect (OSTI)

    Lu, Cimang, E-mail: cimang@adam.t.u-tokyo.ac.jp; Hyun Lee, Choong; Zhang, Wenfeng; Nishimura, Tomonori; Nagashio, Kosuke; Toriumi, Akira [Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8656 (Japan); JST, CREST, 7-3-1 Hongo, Tokyo 113-8656 (Japan)

    2014-03-03

    We have systematically investigated the material and electrical properties of yttrium-doped GeO{sub 2} (Y-GeO{sub 2}) on Germanium (Ge). A significant improvement of both thermal stability and water resistance were demonstrated by Y-GeO{sub 2}/Ge stack, compared to that of pure GeO{sub 2}/Ge stack. The excellent electrical properties of Y-GeO{sub 2}/Ge stacks with low D{sub it} were presented as well as enhancement of dielectric constant in Y-GeO{sub 2} layer, which is beneficial for further equivalent oxide thickness scaling of Ge gate stack. The improvement of thermal stability and water resistance are discussed both in terms of the Gibbs free energy lowering and network modification of Y-GeO{sub 2}.

  3. Inhibitive formation of nanocavities by introduction of Si atoms in Ge nanocrystals produced by ion implantation

    SciTech Connect (OSTI)

    Cai, R. S.; Shang, L.; Liu, X. H.; Zhang, Y. J. [The Cultivation Base for State Key Laboratory, Qingdao University, No. 308 Ningxia Road, Qingdao 266071 (China); Wang, Y. Q., E-mail: yqwang@qdu.edu.cn, E-mail: barba@emt.inrs.ca [The Cultivation Base for State Key Laboratory, Qingdao University, No. 308 Ningxia Road, Qingdao 266071 (China); College of Physics Science, Qingdao University, No. 308 Ningxia Road, Qingdao 266071 (China); Ross, G. G.; Barba, D., E-mail: yqwang@qdu.edu.cn, E-mail: barba@emt.inrs.ca [INRS-Énergie, Matériaux et Télécommunications, 1650 boulevard Lionel-Boulet, Varennes Québec J3X 1S2 (Canada)

    2014-05-28

    Germanium nanocrystals (Ge-nc) were successfully synthesized by co-implantation of Si and Ge ions into a SiO{sub 2} film thermally grown on (100) Si substrate and fused silica (pure SiO{sub 2}), respectively, followed by subsequent annealing at 1150?°C for 1?h. Transmission electron microscopy (TEM) examinations show that nanocavities only exist in the fused silica sample but not in the SiO{sub 2} film on a Si substrate. From the analysis of the high-resolution TEM images and electron energy-loss spectroscopy spectra, it is revealed that the absence of nanocavities in the SiO{sub 2} film/Si substrate is attributed to the presence of Si atoms inside the formed Ge-nc. Because the energy of Si-Ge bonds (301?kJ·mol{sup ?1}) are greater than that of Ge-Ge bonds (264?kJ·mol{sup ?1}), the introduction of the Si-Ge bonds inside the Ge-nc can inhibit the diffusion of Ge from the Ge-nc during the annealing process. However, for the fused silica sample, no crystalline Si-Ge bonds are detected within the Ge-nc, where strong Ge outdiffusion effects produce a great number of nanocavities. Our results can shed light on the formation mechanism of nanocavities and provide a good way to avoid nanocavities during the process of ion implantation.

  4. Testimonials - Partnerships in Fuel Cells - GE Global Research...

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

    Fuel Cells - GE Global Research Testimonials - Partnerships in Fuel Cells - GE Global Research Addthis An error occurred. Try watching this video on www.youtube.com, or enable...

  5. Work & Life at San Ramon | GE Global Research

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

    new window) Click to share on Tumblr (Opens in new window) Employee Organizations GE Software Women's Network TBD Celebrations GE Software Technology Conference This event allows...

  6. Rocket Science? No, It's Harder | GE Global Research

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

    says Juan Albeniz, Business Program Manager, Oil & Gas at GE Global Research Europe. Juan Albeniz, Business Program Manager, Oil & Gas at GE Global Research, Europe Juan...

  7. ME 227 CE 212 MATH 223 GE 210 CMPT 116 ABE 211CHE 210 GE 213# MATH 224

    E-Print Network [OSTI]

    Saskatchewan, University of

    GE 120 ME 227 CE 212 MATH 223 GE 210 CMPT 116 ABE 211CHE 210 GE 213# MATH 224 ABE 295 ABE 212Elective* Elective* AB E 311 ABE 313 ABE 312 GE 348#ABE 323 co-requisite ABE 327 HSS#@ HSS#@ ABE 324 GE 300# ABE 395 4TH YEAR ABE Elec* ABE Elec* ABE Elec*ABE 422 GE 449# Ag Elec* T.E.* T.E.* ABE Elec* Ag Elec

  8. Thermal conductivity of sputtered amorphous Ge films

    SciTech Connect (OSTI)

    Zhan, Tianzhuo; Xu, Yibin; Goto, Masahiro; Tanaka, Yoshihisa; Kato, Ryozo; Sasaki, Michiko; Kagawa, Yutaka [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047 (Japan)] [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047 (Japan)

    2014-02-15

    We measured the thermal conductivity of amorphous Ge films prepared by magnetron sputtering. The thermal conductivity was significantly higher than the value predicted by the minimum thermal conductivity model and increased with deposition temperature. We found that variations in sound velocity and Ge film density were not the main factors in the high thermal conductivity. Fast Fourier transform patterns of transmission electron micrographs revealed that short-range order in the Ge films was responsible for their high thermal conductivity. The results provide experimental evidences to understand the underlying nature of the variation of phonon mean free path in amorphous solids.

  9. Energy band alignment of atomic layer deposited HfO{sub 2} oxide film on epitaxial (100)Ge, (110)Ge, and (111)Ge layers

    SciTech Connect (OSTI)

    Hudait, Mantu K.; Zhu Yan [Advanced Devices and Sustainable Energy Laboratory (ADSEL), Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)

    2013-03-21

    Crystallographically oriented epitaxial Ge layers were grown on (100), (110), and (111)A GaAs substrates by in situ growth process using two separate molecular beam epitaxy chambers. The band alignment properties of atomic layer hafnium oxide (HfO{sub 2}) film deposited on crystallographically oriented epitaxial Ge were investigated using x-ray photoelectron spectroscopy (XPS). Valence band offset, {Delta}E{sub v} values of HfO{sub 2} relative to (100)Ge, (110)Ge, and (111)Ge orientations were 2.8 eV, 2.28 eV, and 2.5 eV, respectively. Using XPS data, variation in valence band offset, {Delta}E{sub V}(100)Ge>{Delta}E{sub V}(111)Ge>{Delta}E{sub V}(110)Ge, was obtained related to Ge orientation. Also, the conduction band offset, {Delta}E{sub c} relation, {Delta}E{sub c}(110)Ge>{Delta}E{sub c}(111)Ge>{Delta}E{sub c}(100)Ge related to Ge orientations was obtained using the measured bandgap of HfO{sub 2} on each orientation and with the Ge bandgap of 0.67 eV. These band offset parameters for carrier confinement would offer an important guidance to design Ge-based p- and n-channel metal-oxide field-effect transistor for low-power application.

  10. GE Appliances: Order (2010-CE-2113)

    Broader source: Energy.gov [DOE]

    DOE issued an Order after entering into a Compromise Agreement with General Electric Appliances after finding GE Appliances had failed to certify that certain models of dehumidifiers comply with the applicable energy conservation standards.

  11. Researching NDE, Additive Manufacturing |GE Global Research

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

    I never thought I would get the incredible opportunity to become a summer intern at the GE Global Research Center, amongst such brilliant and tenacious individuals. I have been...

  12. GE's Christine Furstoss Named to NACIE

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

    in Niskayuna, NY, Christine is responsible for working with both R&D leaders at GE's industrial businesses and with strategic partners to set strategy for growth, and to...

  13. Electric polarizabilities of Ge(CH{sub 3}){sub 4} from collision-induced light-scattering experiments and ab initio calculations

    SciTech Connect (OSTI)

    Maroulis, G.; Hohm, Uwe [Department of Chemistry, University of Patras, GR-26500 Patras (Greece); Institut fuer Physikalische und Theoretische Chemie der Technischen, Universitaet Braunschweig, Hans-Sommer-Strasse 10, D-38106 Braunschweig (Germany)

    2007-09-15

    The dipole-quadrupole and dipole-octopole polarizabilities A and E of Ge(CH{sub 3}){sub 4} have been determined from collision-induced light-scattering experiments and ab initio calculations. Our experimental results are |A|/e{sup 2}a{sub 0}{sup 3}E{sub h}{sup -1}<143 and |E|/e{sup 2}a{sub 0}{sup 4}E{sub h}{sup -1}<545. Our best theoretical values are A=45.48 and E=-389.9, respectively. The calculated value for the dipole polarizability is {alpha}/e{sup 2}a{sub 0}{sup 2}E{sub h}{sup -1}=83.26, in fine accord with our static experimental estimate of 83.2. We present a detailed discussion of the level of agreement between experiment and theory.

  14. GE Announces Vic Abate as New Chief Technology Officer | GE Global...

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

    Industrial Internet and Brilliant Factory. This transition marks another chapter in GE's transformation to become the world's premiere Digital Industrial company. Enabled by a...

  15. Be a part of something bigger than yourself GE Healthcare

    E-Print Network [OSTI]

    Rimon, Elon

    Be a part of something bigger than yourself GE Healthcare Position: Mechanical Engineer as a contractor · Working at GE site at Tirat-Carmel. · Start: immediately · Duration 6-10 months, with optional elongation. ElgemsMoked@ge.com-CV www.gehealthcare.com We are GE Healthcare, a $17 billion division

  16. UC IRVINE GENERAL EDUCATION (GE) REQUIREMENT AND APPROVED GE COURSES, 201213 Includes course titles and Schedule of Classes designations

    E-Print Network [OSTI]

    Loudon, Catherine

    UC IRVINE GENERAL EDUCATION (GE) REQUIREMENT AND APPROVED GE COURSES, 2012­13 Includes course titles and Schedule of Classes designations GENERAL EDUCATION (GE) REQUIREMENT UCI is committed undergraduates complete a set of general education (GE) requirements. General education courses introduce

  17. 2009-10 Princeton Global Scholar Ge Zhaoguang. Professor Ge is the founding director of the National Institute for Advanced

    E-Print Network [OSTI]

    2009-10 Princeton Global Scholar Ge Zhaoguang. Professor Ge is the founding director, and emendation of all sorts of newly discovered texts (mostly found at archaeological sites). Professor Ge University, Professor Ge taught at Tsinghua University for a number of years. He is known for many important

  18. Measurement of the direct energy gap of coherently strained SnxGe1x Ge,,001... heterostructures

    E-Print Network [OSTI]

    Atwater, Harry

    Measurement of the direct energy gap of coherently strained SnxGe1Àx ÕGe,,001... heterostructures The direct energy gap has been measured for coherently strained SnxGe1 x alloys on Ge 001 substrates with 0 for coherently strained SnxGe1 x alloys indicates a large alloy contribution and a small strain contribution

  19. GE Advising & Registration Students FT Faculty PT Faculty Admin Unit 4 Other Staff Students have access to quality GE advising

    E-Print Network [OSTI]

    de Lijser, Peter

    GE Advising & Registration Students FT Faculty PT Faculty Admin Unit 4 Other Staff Students have access to quality GE advising 9% 13% 11% 13% 10% 8% Faculty can easily advise students on GE requirements 10% 18% 9% 24% 33% 11% Staff academic advisors can easily advise students on GE requirements 8% 11

  20. Ge{sub 1-y}Sn{sub y} (y = 0.01-0.10) alloys on Ge-buffered Si: Synthesis, microstructure, and optical properties

    SciTech Connect (OSTI)

    Senaratne, C. L.; Kouvetakis, J. [Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-1604 (United States); Gallagher, J. D.; Jiang, Liying; Smith, D. J.; Menéndez, J. [Department of Physics, Arizona State University, Tempe, Arizona 85287-1504 (United States); Aoki, Toshihiro [LeRoy Eyring Center for Solid State Science, Arizona State University, Tempe, Arizona 85287-1704 (United States)

    2014-10-07

    Novel hydride chemistries are employed to deposit light-emitting Ge{sub 1-y}Sn{sub y} alloys with y ? 0.1 by Ultra-High Vacuum Chemical Vapor Deposition (UHV-CVD) on Ge-buffered Si wafers. The properties of the resultant materials are systematically compared with similar alloys grown directly on Si wafers. The fundamental difference between the two systems is a fivefold (and higher) decrease in lattice mismatch between film and virtual substrate, allowing direct integration of bulk-like crystals with planar surfaces and relatively low dislocation densities. For y ? 0.06, the CVD precursors used were digermane Ge?H? and deuterated stannane SnD?. For y ? 0.06, the Ge precursor was changed to trigermane Ge?H?, whose higher reactivity enabled the fabrication of supersaturated samples with the target film parameters. In all cases, the Ge wafers were produced using tetragermane Ge?H?? as the Ge source. The photoluminescence intensity from Ge{sub 1–y}Sn{sub y}/Ge films is expected to increase relative to Ge{sub 1–y}Sn{sub y}/Si due to the less defected interface with the virtual substrate. However, while Ge{sub 1–y}Sn{sub y}/Si films are largely relaxed, a significant amount of compressive strain may be present in the Ge{sub 1–y}Sn{sub y}/Ge case. This compressive strain can reduce the emission intensity by increasing the separation between the direct and indirect edges. In this context, it is shown here that the proposed CVD approach to Ge{sub 1–y}Sn{sub y}/Ge makes it possible to approach film thicknesses of about 1 ?m, for which the strain is mostly relaxed and the photoluminescence intensity increases by one order of magnitude relative to Ge{sub 1–y}Sn{sub y}/Si films. The observed strain relaxation is shown to be consistent with predictions from strain-relaxation models first developed for the Si{sub 1–x}Ge{sub x}/Si system. The defect structure and atomic distributions in the films are studied in detail using advanced electron-microscopy techniques, including aberration corrected STEM imaging and EELS mapping of the average diamond–cubic lattice.

  1. Relaxation and recombination processes in Ge/SiGe multiple quantum wells

    SciTech Connect (OSTI)

    Gatti, E., E-mail: gatti@mater.unimib.it; Giorgioni, A., E-mail: gatti@mater.unimib.it; Grilli, E., E-mail: gatti@mater.unimib.it; Guzzi, M., E-mail: gatti@mater.unimib.it [L-NESS and Università di Milano-Bicocca, Dip. di Scienza dei Materiali, via Cozzi 53, 20125 Milano (Italy); Chrastina, D.; Isella, G. [L-NESS and Politecnico di Milano, Dip. di Fisica, via Anzani 42, 22100 Como (Italy); Chernikov, A.; Kolata, K.; Bornwasser, V.; Köster, N. S.; Woscholski, R.; Chatterjee, S. [Faculty of Physics and Materials Sciences Center, Philipps-Universität, Renthof 5, 35032 Marburg (Germany)

    2013-12-04

    The carrier dynamics that occurs in Ge/SiGe QWs when electrons are excited to confined states at ? is studied by means of optical spectroscopy at different lattice temperatures. The typical times for the different relaxation and recombination processes are given and discussed.

  2. Ge/SiGe quantum wells on Si(111): Growth, structural, and optical properties

    SciTech Connect (OSTI)

    Gatti, E., E-mail: eleonora.gatti@mater.unimib.it; Pezzoli, F.; Grilli, E. [L-NESS and Dipartimento di Scienza dei Materiali, Università di Milano Bicocca, via Cozzi 55, I-20125 Milano (Italy); Isa, F.; Chrastina, D.; Isella, G. [L-NESS and Dipartimento di Fisica, Politecnico di Milano, Polo di Como, via Anzani 42, I - 22100 Como (Italy); Müller Gubler, E. [Electron Microscopy Center of ETH Zürich (EMEZ), August-Piccard-Hof 1, CH-8093 Zürich (Switzerland)

    2014-07-28

    The epitaxial growth of Ge/Si{sub 0.15}Ge{sub 0.85} multiple quantum wells (MQWs) on Si(111) substrates is demonstrated. A 3??m thick reverse, double-step virtual substrate with a final composition of Si{sub 0.10}Ge{sub 0.90} has been employed. High resolution XRD, TEM, AFM and defect etching analysis has been used for the study of the structural properties of the buffer and of the QWs. The QW stack is characterized by a threading dislocation density of about 3?×?10{sup 7?}cm{sup ?2} and an interdiffusion layer at the well/barrier interface of 2.1?nm. The quantum confined energy levels of this system have been calculated using the k·p and effective mass approximation methods. The Ge/Si{sub 0.15}Ge{sub 0.85} MQWs have been characterized through absorption and photoluminescence measurements. The optical spectra have been compared with those of Ge/Si{sub 0.15}Ge{sub 0.85} QWs grown on Si(001) through a thick graded virtual substrate.

  3. Optical Link on Silicon Employing Ge/SiGe Quantum Well Structures Onur Fidaner, Ali K. Okyay, Jonathan E. Roth, Rebecca K. Scheavitz, Yu-Hsuan Kuo*

    E-Print Network [OSTI]

    Miller, David A. B.

    Optical Link on Silicon Employing Ge/SiGe Quantum Well Structures Onur Fidaner, Ali K. Okyay University, Taipei, Taiwan Abstract: We demonstrate an optical link on silicon employing Ge/SiGe quantum well of the quantum-confined Stark effect (QCSE) on silicon using Ge/SiGe quantum wells opened up the possibility

  4. 23 6 12 8:00 III-V/Ge CMOS

    E-Print Network [OSTI]

    Katsumoto, Shingo

    23 6 12 8:00 - 1 - 1. : III-V/Ge CMOS ~ 200%~ 2. : III-V (Ge) III-V/Ge CMOS (Si) 200% III-V/Ge CMOS 200% III-V/Ge CMOS () () () () III-V III-V/Ge CMOS (1) III-V Ge III-V/Ge CMOS (2) III-V-OI MOSFET (3) III-V/Ge CMOS "2011 Symposia on VLSI

  5. Study of Pu consumption in advanced light water reactors: Evaluation of GE advanced boiling water reactor plants - compilation of Phase 1B task reports

    SciTech Connect (OSTI)

    1993-09-15

    This report contains an extensive evaluation of GE advanced boiling water reactor plants prepared for United State Department of Energy. The general areas covered in this report are: core and system performance; fuel cycle; infrastructure and deployment; and safety and environmental approval.

  6. Measurement of the neutron-capture cross section of ??Ge and ??Ge below 15 MeV and its relevance to 0??? decay searches of ??Ge

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

    Bhike, Megha; Fallin, B.; Tornow, W.

    2015-02-01

    The neutron radiative-capture cross section of ??Ge was measured between 0.4 and 14.8 MeV using the activation technique. Germanium samples with the isotopic abundance of ~86% ??Ge and ~14% ??Ge used in the 0??? searches by the GERDA and Majorana Collaborations were irradiated with monoenergetic neutrons produced at eleven energies via the ³H(p,n)³He, ²H(d,n)³He and ³H(d,n)?He reactions. Previously, data existed only at thermal energies and at 14 MeV. As a by-product, capture cross-section data were also obtained for ??Ge at neutron energies below 8 MeV. Indium and gold foils were irradiated simultaneously for neutron fluence determination. High-resolution ?-ray spectroscopy wasmore »used to determine the ?-ray activity of the daughter nuclei of interest. For the ??Ge total capture cross section the present data are in good agreement with the TENDL-2013 model calculations and the ENDF/B-VII.1 evaluations, while for the ??Ge(n,?)??Ge reaction, the present data are about a factor of two larger than predicted. It was found that the ??Ge(n,?)??Ge yield in the High-Purity Germanium (HPGe) detectors used by the GERDA and Majorana Collaborations is only about a factor of two smaller than the ??Ge(n,?)??Ge yield due to the larger cross section of the former reaction.« less

  7. Phase transitions in Ge-Sb phase change materials

    SciTech Connect (OSTI)

    Raoux, Simone; Virwani, Kumar; Hitzbleck, Martina; Salinga, Martin; Madan, Anita; Pinto, Teresa L.

    2009-03-15

    Thin films of the phase change material Ge-Sb with Ge concentrations between 7.3 and 81.1 at. % were deposited by cosputtering from elemental targets. Their crystallization behavior was studied using time-resolved x-ray diffraction, Auger electron spectroscopy, differential scanning calorimetry, x-ray reflectivity, profilometry, optical reflectivity, and resistivity versus temperature measurements. It was found that the crystallization temperature increases with Ge content. Calculations of the glass transition temperature (which is a lower limit for the crystallization temperature T{sub x}) also show an increase with Ge concentration closely tracking the measured values of T{sub x}. For low Ge content samples, Sb x-ray diffraction peaks occurred during a heating ramp at lower temperature than Ge diffraction peaks. The appearance of Ge peaks is related to Ge precipitation and agglomeration. For Ge concentrations of 59.3 at. % and higher, Sb and Ge peaks occurred at the same temperature. Upon crystallization, film mass density and optical reflectivity increase as well as electrical contrast (ratio of resistivity in amorphous phase to crystalline phase) all showed a maximum for the eutectic alloy (14.5 at. % Ge). For the alloy with 59.3 at. % Ge there was very little change in any of these parameters, while the alloy with 81.1 at. % Ge behaved opposite to a typical phase change alloy and showed reduced mass density and reflectivity and increased resistivity.

  8. Updated 8/28/2014 New GE Requirements & Environmental Studies Advising

    E-Print Network [OSTI]

    Updated 8/28/2014 New GE Requirements & Environmental Studies Advising Course Concentration(s) Lower Division GE Upper Division GE Overlay(s) AIS 310

  9. Viscosity Measurement G.E. Leblanc

    E-Print Network [OSTI]

    Kostic, Milivoje M.

    30 Viscosity Measurement G.E. Leblanc McMaster University R.A. Secco The University of Western and Non-Newtonian Fluids l Dimensions and Units of Viscosity l Viscometer Types l Capillary M. Kostic must be supplied (1) to create viscous flow units by breaking bonds between atoms and molecules, and (2

  10. 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...

  11. Metastability and relaxation in tensile SiGe on Ge(001) virtual substrates

    SciTech Connect (OSTI)

    Frigerio, Jacopo; Lodari, Mario; Chrastina, Daniel, E-mail: daniel.chrastina@polimi.it; Mondiali, Valeria; Isella, Giovanni [L-NESS, Dipartimento di Fisica, Politecnico di Milano, Polo di Como, via Anzani 42, 22100 Como (Italy); Bollani, Monica [IFN-CNR, L-NESS, via Anzani 42, 22100 Como (Italy)

    2014-09-21

    We systematically study the heteroepitaxy of SiGe alloys on Ge virtual substrates in order to understand strain relaxation processes and maximize the tensile strain in the SiGe layer. The degree of relaxation is measured by high-resolution x-ray diffraction, and surface morphology is characterized by atomic force microscopy. The results are analyzed in terms of a numerical model, which considers dislocation nucleation, multiplication, thermally activated glide, and strain-dependent blocking. Relaxation is found to be sensitive to growth rate and substrate temperature as well as epilayer misfit and thickness, and growth parameters are found which allow a SiGe film with over 4 GPa of tensile stress to be obtained.

  12. GE partners with 'Girls Who Code' for summer program | GE Global...

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

    offered 19 programs and counted 375 participants; this year, Girls Who Code will offer 60 programs reaching close to 1,200 girls in nine cities nationwide. GE joins other...

  13. Energy Secretary Chu to Tour GE Global Research Advanced Manufacturing...

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

    Energy Secretary Chu to Tour GE Global Research Advanced Manufacturing Lab Energy Secretary Chu to Tour GE Global Research Advanced Manufacturing Lab May 24, 2012 - 10:54am Addthis...

  14. Butterfly-Inspired Thermal Imaging | GE Global Research

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

    GE Innovation and Manufacturing in Europe 2-4-13-v-3d-printing-medical-devices Additive Manufacturing Demonstration at GE Global Research 2-3-10-v Crowdsourcing...

  15. What Happens in Research-Based Design | GE Global Research

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

    paths we have at GE Global Research ("GE Leaders are Researchers Too",). The field of gas turbine heat transfer is growing in importance, and as a result, we have a lot of job...

  16. OPTIMIZATION OF a-SiGe BASED TRIPLE, TANDEM AND SINGLE-JUNCTION SOLAR Xunming Deng

    E-Print Network [OSTI]

    Deng, Xunming

    OPTIMIZATION OF a-SiGe BASED TRIPLE, TANDEM AND SINGLE-JUNCTION SOLAR CELLS Xunming Deng Department, tandem and triple-junction a-SiGe based solar cells and materials [6-19]. Much of the research is also light and bias voltage for the measurement of multiple-junction cells. Materials characterization using

  17. Similarity of Stranski-Krastanow growth of Ge/Si and SiGe/Si (001)

    SciTech Connect (OSTI)

    Norris, D. J.; Qiu, Y.; Walther, T. [Department of Electronic and Electrical Engineering, University of Sheffield, Mappin Building, Mappin Street, Sheffield S1 3JD (United Kingdom); Dobbie, A.; Myronov, M. [Department of Physics, University of Warwick, Coventry CV4 7A (United Kingdom)

    2014-01-07

    This study investigates the onset of islanding (Stranski-Krastanow transition) in strained pure germanium (Ge) and dilute silicon-germanium (SiGe) alloy layers grown by chemical vapour deposition on Si(001) substrates. Integration of compositional profiles is compared to a novel method for quantification of X-ray maps acquired in cross-sectional scanning transmission electron microscopy, together with simulations of surface segregation of Ge. We show that Si{sub 1?x}Ge{sub x} alloys for germanium concentrations x???0.27 grow two-dimensionally and stay flat up to considerable layer thicknesses, while layers with concentrations in the range 0.28?Ge is ±(0.2–0.3) ML. Modelling shows that of the amount of germanium deposited, 0.7 ML segregate towards the free surface so that only ?2.3/x ML are directly incorporated in the layer within a few nanometres, in good agreement with our measurements. For pure Ge (x?=?1), this thickness is smaller than most values quoted in the literature, which we attribute to the high sensitivity of our method to fractional monolayer changes in the effective chemical width of such thin layers.

  18. Strain and stability of ultrathin Ge layers in Si/Ge/Si axial heterojunction nanowires

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

    Ross, Frances M.; Stach, Eric A.; Wen, Cheng -Yen; Reuter, Mark C.; Su, Dong

    2015-02-05

    The abrupt heterointerfaces in the Si/Ge materials system presents useful possibilities for electronic device engineering because the band structure can be affected by strain induced by the lattice mismatch. In planar layers, heterointerfaces with abrupt composition changes are difficult to realize without introducing misfit dislocations. However, in catalytically grown nanowires, abrupt heterointerfaces can be fabricated by appropriate choice of the catalyst. Here we grow nanowires containing Si/Ge and Si/Ge/Si structures respectively with sub-1nm thick Ge "quantum wells" and we measure the interfacial strain fields using geometric phase analysis. Narrow Ge layers show radial strains of several percent, with a correspondingmore »dilation in the axial direction. Si/Ge interfaces show lattice rotation and curvature of the lattice planes. We conclude that high strains can be achieved, compared to what is possible in planar layers. In addition, we study the stability of these heterostructures under heating and electron beam irradiation. The strain and composition gradients are supposed to the cause of the instability for interdiffusion.« less

  19. Thin SiGe virtual substrates for Ge heterostructures integration on silicon

    SciTech Connect (OSTI)

    Cecchi, S., E-mail: stefano.cecchi@mdm.imm.cnr.it; Chrastina, D.; Frigerio, J.; Isella, G. [L-NESS, Dipartimento di Fisica, Politecnico di Milano–Polo Territoriale di Como, Via Anzani 42, I-22100 Como (Italy); Gatti, E.; Guzzi, M. [L-NESS, Dipartimento di Scienza dei Materiali, Università di Milano Bicocca, via Cozzi 53, I-20126 Milano (Italy); Müller Gubler, E. [Electron Microscopy ETH Zurich, ETH Zurich, Auguste-Piccard-Hof 1, CH-8093 Zurich (Switzerland); Paul, D. J. [School of Engineering, University of Glasgow, Rankine Building, Oakfield Avenue, Glasgow G12 8LT (United Kingdom)

    2014-03-07

    The possibility to reduce the thickness of the SiGe virtual substrate, required for the integration of Ge heterostructures on Si, without heavily affecting the crystal quality is becoming fundamental in several applications. In this work, we present 1??m thick Si{sub 1?x}Ge{sub x} buffers (with x?>?0.7) having different designs which could be suitable for applications requiring a thin virtual substrate. The rationale is to reduce the lattice mismatch at the interface with the Si substrate by introducing composition steps and/or partial grading. The relatively low growth temperature (475?°C) makes this approach appealing for complementary metal-oxide-semiconductor integration. For all the investigated designs, a reduction of the threading dislocation density compared to constant composition Si{sub 1?x}Ge{sub x} layers was observed. The best buffer in terms of defects reduction was used as a virtual substrate for the deposition of a Ge/SiGe multiple quantum well structure. Room temperature optical absorption and photoluminescence analysis performed on nominally identical quantum wells grown on both a thick graded virtual substrate and the selected thin buffer demonstrates a comparable optical quality, confirming the effectiveness of the proposed approach.

  20. Monolithic Ge/Si Avalanche Photodiodes Yimin Kanga*

    E-Print Network [OSTI]

    Bowers, John

    Monolithic Ge/Si Avalanche Photodiodes Yimin Kanga* , Mike Morsea , Mario J. Panicciaa , Moshe, Charlottesville, VA 22904, USA Abstract: We demonstrate mesa-type and waveguide-type Ge/Si avalanche photodiodes. Research on the Ge/Si photodiodes, one of the fundamental components needed for building integrated silicon

  1. MOTION OF ELECTRON-HOLE DROPS IN Ge

    E-Print Network [OSTI]

    Westervelt, R.M.

    2011-01-01

    MOTION OF ELECTRON-HOLE DROPS IN Ge R. M. Westervelt, J. C.MOTION OF ELECTRON-HOLE DROPS IN Ge R. M. Westervelt, J. C.OF ELECTRON-HOLE DROPS IN Ge R M Westervelt, J C Culbertson

  2. Conduction band discontinuity and electron confinement at the Si[subscript x]Ge[subscript 1?x]/Ge interface

    E-Print Network [OSTI]

    Mazzeo, G.

    Germanium rich heterostructures can constitute a valid alternative to Silicon for the confinement of single electron spins. The conduction band discontinuity in SiGe/Ge heterostructures grown on pure germanium substrate ...

  3. Properties of excited states in {sup 77}Ge.

    SciTech Connect (OSTI)

    Kay, B. P.; Chiara, C. J.; Schiffer, J. P.; Kondev, F. G.; Zhu, S.; Carpenter, M. P.; Janssens, R. V. F.; Lauritsen, T.; Lister, C. J.; McCutchan, E. A.; Seweryniak, D.; Stefanescu, I.; Univ. of Maryland; Horia-Hulubei National Inst. for Physics and Nuclear Engineering

    2009-07-01

    The nucleus {sup 77}Ge was studied through the {sup 76}Ge({sup 13}C,{sup 12}C){sup 77}Ge reaction at a sub-Coulomb energy. The angular distributions of rays depopulating excited states in {sup 77}Ge were measured in order to constrain spin and parity assignments. Some of these assignments are of use in connection with neutrinoless double beta decay, where the population of states near the Fermi surface of {sup 76}Ge was recently explored using transfer reactions.

  4. Particle Production at 3 GeV X. Ding, UCLA

    E-Print Network [OSTI]

    McDonald, Kirk

    = 50m 0.02976 (neg: 0.01206, pos: 0.01770) Carbon 3 GeV, Z = 0m 0.03341 (neg: 0.01370, pos: 0.01971) Mercury 3 GeV, Z = 50 m 0.02096 (neg: 0.01070, pos: 0.01026) Mercury 3 GeV, Z = 0 m 0.02496 (neg: 0.01273, pos: 0.01223) Mercury 8 GeV, Z = 50 m 0.0263 (neg: 0.0136, pos: 0.0127) Mercury 8 GeV, Z = 0m 0

  5. Role of nucleation sites on the formation of nanoporous Ge

    SciTech Connect (OSTI)

    Yates, B. R.; Darby, B. L.; Jones, K. S. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611-6400 (United States); Elliman, R. G. [Department of Electronic Materials Engineering, Research School of Physical Sciences and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia)

    2012-09-24

    The role of nucleation sites on the formation of nanoporous Ge was investigated. Three Ge films with different spherical or columnar pore morphologies to act as inherent nucleation sites were sputtered on (001) Ge. Samples were implanted 90 Degree-Sign from incidence at 300 keV with fluences ranging from 3.0 Multiplication-Sign 10{sup 15} to 3.0 Multiplication-Sign 10{sup 16} Ge{sup +}/cm{sup 2}. Electron microscopy investigations revealed varying thresholds for nanoporous Ge formation and exhibited a stark difference in the evolution of the Ge layers based on the microstructure of the initial film. The results suggest that the presence of inherent nucleation sites significantly alters the onset and evolution of nanoporous Ge.

  6. Monolayer Passivation of Ge(100) Surface via Nitridation and Oxidation Joon Sung Leea,b

    E-Print Network [OSTI]

    Kummel, Andrew C.

    Monolayer Passivation of Ge(100) Surface via Nitridation and Oxidation Joon Sung Leea,b , Sarah R passivation of Ge(100) surface via formation of Ge-N and Ge-O surface species was studied using scanning cyclotron resonance (ECR) plasma source formed an ordered Ge-N structure on a Ge(100) surface at 500o C. DFT

  7. Prompt Gamma Rays in {sup 77}Ge after Neutron Capture on {sup 76}Ge

    SciTech Connect (OSTI)

    Meierhofer, Georg; Grabmayr, Peter; Jochum, Josef [Physikalisches Institut, Eberhard Karls Universitaet Tuebingen, Auf der Morgenstelle 14, 72076 Tuebingen (Germany); Canella, Lea [Institut fuer Radiochemie, Technische Universitaet Muenchen, Walther-Meissner-Str. 3, 85748 Garching (Germany); Jolie, Jan; Kudejova, Petra; Warr, Nigel [Institut fuer Kernphysik, Universitaet zu Koeln, Zuelpicher Str. 77, 50937 Cologne (Germany)

    2009-01-28

    The observation of neutrinoless double beta decay would be proof of the Majorana nature of the neutrino. Half-lives for these decays are very long (for {sup 76}Ge:>10{sup 25} y), so background reduction and rejection is the major task for double beta experiments. The GERDA (GERmanium Detector Array) experiment at the Gran Sasso Laboratory of the INFN (LNGS) searches for neutrinoless double beta decay of {sup 76}Ge. The isotope {sup 76}Ge is an ideal candidate because it can be used as source and detector at the same time. A large remaining contribution to the background arises from the prompt gamma cascade after neutron capture by {sup 76}Ge followed by {beta}{sup -}-decay of {sup 77}Ge. Since the prompt gamma decay scheme is poorly known, measurements with isotopically enriched Germanium samples were carried out at the PGAA facility at the research reactor FRM II (Munich). With the known prompt gamma spectrum it will be possible to improve the overall veto efficiency of the GERDA experiment.

  8. Material properties in SiGe/Ge quantum wells Rebecca K. Schaevitz*, Jonathan E. Roth, Onur Fidaner, and David A. B. Miller

    E-Print Network [OSTI]

    Miller, David A. B.

    Material properties in SiGe/Ge quantum wells Rebecca K. Schaevitz*, Jonathan E. Roth, Onur Fidaner *Corresponding author: rschaevitz@stanford.edu Abstract: Photocurrent measurements in Ge quantum wells parameters for design of high-performance SiGe/Ge quantum well optoelectronics on silicon. Germanium

  9. Ge/SiGe Quantum Confined Stark Effect Modulators on Silicon James S. Harris, Yu-Hsuan Kuo, and David A. B. Miller

    E-Print Network [OSTI]

    Miller, David A. B.

    Ge/SiGe Quantum Confined Stark Effect Modulators on Silicon James S. Harris, Yu-Hsuan Kuo bandwidth have been demonstrated [4]. 2. Quantum well design Ge is an indirect band gap material, but it has. In order to have good quantum confinement, SiGe barriers are used since Si and Ge have a very high direct

  10. Interface and nanostructure evolution of cobalt germanides on Ge(001)

    SciTech Connect (OSTI)

    Grzela, T., E-mail: grzela@ihp-microelectronics.com; Schubert, M. A. [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Koczorowski, W. [London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London, WC1H 0AH,United Kingdom (United Kingdom); Institute of Physics, Poznan University of Technology, Nieszawska 13A, 60-965 Poznan (Poland); Capellini, G. [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Dipartimento di Scienze, Università degli Studi Roma Tre, I-00146 Roma (Italy); Czajka, R. [Institute of Physics, Poznan University of Technology, Nieszawska 13A, 60-965 Poznan (Poland); Radny, M. W. [Institute of Physics, Poznan University of Technology, Nieszawska 13A, 60-965 Poznan (Poland); School of Mathematical and Physical Sciences, The University of Newcastle, University Drive, Callaghan NSW, 2308 (Australia); Curson, N.; Schofield, S. R. [London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London, WC1H 0AH,United Kingdom (United Kingdom); Schroeder, T. [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); BTU Cottbus, Konrad-Zuse Str. 1, 03046 Cottbus (Germany)

    2014-02-21

    Cobalt germanide (Co{sub x}Ge{sub y}) is a candidate system for low resistance contact modules in future Ge devices in Si-based micro and nanoelectronics. In this paper, we present a detailed structural, morphological, and compositional study on Co{sub x}Ge{sub y} formation on Ge(001) at room temperature metal deposition and subsequent annealing. Scanning tunneling microscopy and low energy electron diffraction clearly demonstrate that room temperature deposition of approximately four monolayers of Co on Ge(001) results in the Volmer Weber growth mode, while subsequent thermal annealing leads to the formation of a Co-germanide continuous wetting layer which evolves gradually towards the growth of elongated Co{sub x}Ge{sub y} nanostructures. Two types of Co{sub x}Ge{sub y} nanostructures, namely, flattop- and ridge-type, were observed and a systematic study on their evolution as a function of temperature is presented. Additional transmission electron microscopy and x-ray photoemission spectroscopy measurements allowed us to monitor the reaction between Co and Ge in the formation process of the Co{sub x}Ge{sub y} continuous wetting layer as well as the Co{sub x}Ge{sub y} nanostructures.

  11. Colon Cancer Mapping | GE Global Research

    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 OutreachProductswsicloudwsiclouddenDVA N C E D BGene NetworkNuclearDNP 20082 P2014 CollegiateVanderbilt, GE Team

  12. Crowdsourcing Software Announcement | GE Global Research

    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 Administration would like submit theCovalent Bonding in Actinide SandwichCrayCrosscuttingGE, MIT Build

  13. Crowdsourcing Software Award | GE Global Research

    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 Administration would like submit theCovalent Bonding in Actinide SandwichCrayCrosscuttingGE, MIT

  14. Patent Record Announcement | GE Global Research

    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 Administration wouldMass mapSpeeding access| Department ofStephenSkinner,Past and Present EERE Budget PastGE's

  15. Game Changing Technology | GE Global Research

    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 Room NewsInformation Current HABFESOpportunities Nuclear PhysicsGE GlobalGetting&Tools »GambitI

  16. Direct band gap optical emission from compressively strained Ge films grown on relaxed Si{sub 0.5}Ge{sub 0.5} substrate

    SciTech Connect (OSTI)

    Aluguri, R.; Manna, S.; Ray, S. K. [Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India)] [Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India)

    2013-10-14

    Compressively strained Ge films have been grown on relaxed Si{sub 0.5}Ge{sub 0.5} virtual substrate in ultra high vacuum using molecular beam epitaxy. Structural characterization has shown that the Ge films are compressively strained with partial strain relaxation in a film thicker than 3.0 nm, due to onset of island nucleation. Photoluminescence spectra exhibit the splitting of degenerate Ge valence band into heavy hole and light hole bands with a broad direct band gap emission peak around 0.81 eV. Temperature and excitation power dependent emission characteristics have been studied to investigate the mechanism of luminescence quenching at high temperatures and the role of non-radiative recombination centers.

  17. Study of the low-lying states of Ge2 and Ge2 using negative ion zero electron kinetic energy spectroscopy

    E-Print Network [OSTI]

    Neumark, Daniel M.

    Study of the low-lying states of Ge2 and Ge2 using negative ion zero electron kinetic energy The low-lying states of Ge2 and Ge2 are probed using negative ion zero electron kinetic energy ZEKE spectroscopy. The ZEKE spectrum of Ge2 yields an electron affinity of 2.035 0.001 eV for Ge2, as well as term

  18. Cs6Ge8Zn: A Zintl Phase with Isolated Heteroatomic Clusters of Ge8Zn

    E-Print Network [OSTI]

    a single phase of Cs6Ge8Zn.8 The plate-like crystals of the compound are brittle, black, and with coal-like luster. Single-crystal studies unveiled a new type of cluster formation, a dimer of corner different types. The clusters of type A have only a horizontal mirror plane (Cm) while the clusters of type

  19. GeV emission from Gamma-Ray Burst afterglows

    E-Print Network [OSTI]

    A. Panaitescu

    2008-01-10

    We calculate the GeV afterglow emission expected from a few mechanisms related to GRBs and their afterglows. Given the brightness of the early X-ray afterglow emission measured by Swift/XRT, GLAST/LAT should detect the self-Compton emission from the forward-shock driven by the GRB ejecta into the circumburst medium. Novel features discovered by Swift in X-ray afterglows (plateaus and chromatic light-curve breaks) indicate the existence of a pair-enriched, relativistic outflow located behind the forward shock. Bulk and inverse-Compton upscattering of the prompt GRB emission by such outflows provide another source of GeV afterglow emission detectable by LAT. The large-angle burst emission and synchrotron forward-shock emission are, most likely, too dim at high photon energy to be observed by LAT. The spectral slope of the high-energy afterglow emission and its decay rate (if it can be measured) allow the identification of the mechanism producing the GeV transient emission following GRBs.

  20. Structure and vibrations of different charge Ge impurity in ?-quartz

    SciTech Connect (OSTI)

    Kislov, A. N., E-mail: a.n.kislov@urfu.ru; Mikhailovich, A. P., E-mail: a.n.kislov@urfu.ru; Zatsepin, A. F., E-mail: a.n.kislov@urfu.ru [Ural Federal University, 19 Mira St., Yekaterinburg, 620002 (Russian Federation)

    2014-10-21

    Atomic structure and localized vibrations of ??SiO{sub 2}:Ge are studied using computer modeling techniques. The simulation was carried out by the lattice dynamics calculation of the local density of vibrational states. Local structures parameters are calculated, localized symmetrized vibrations frequency caused by Ge impurity in different charge states are defined. The movements of atoms located near Ge impurity are analyzed and their contribution into localized vibrations of different type is evaluated.

  1. Structural and phonon transmission study of Ge-Au-Ge eutectically bonded interfaces

    SciTech Connect (OSTI)

    Knowlton, W.B. [Univ. of California, Berkeley, CA (United States). Dept. of Materials Science and Mineral Engineering]|[Lawrence Berkeley Lab., CA (United States). Materials Sciences Div.

    1995-07-01

    This thesis presents a structural analysis and phonon transparency investigation of the Ge-Au-Ge eutectic bond interface. Interface development was intended to maximize the interfacial ballistic phonon transparency to enhance the detection of the dark matter candidate WIMPs. The process which was developed provides an interface which produces minimal stress, low amounts of impurities, and insures Ge lattice continuity through the interface. For initial Au thicknesses of greater than 1,000 {angstrom} Au per substrate side, eutectic epitaxial growth resulted in a Au dendritic structure with 95% cross sectional and 90% planar Au interfacial area coverages. In sections in which Ge bridged the interface, lattice continuity across the interface was apparent. Epitaxial solidification of the eutectic interface with initial Au thicknesses < 500 A per substrate side produced Au agglomerations thereby reducing the Au planar interfacial area coverage to as little as 30%. The mechanism for Au coalescence was attributed to lateral diffusion of Ge and Au in the liquid phase during solidification. Phonon transmission studies were performed on eutectic interfaces with initial Au thicknesses of 1,000 {angstrom}, 500 {angstrom}, and 300 {angstrom} per substrate side. Phonon imaging of eutectically bonded samples with initial Au thicknesses of 300 {angstrom}/side revealed reproducible interfacial percent phonon transmissions from 60% to 70%. Line scan phonon imaging verified the results. Phonon propagation TOF spectra distinctly showed the predominant phonon propagation mode was ballistic. This was substantiated by phonon focusing effects apparent in the phonon imaging data. The degree of interface transparency to phonons and resulting phonon propagation modes correlate with the structure of the interface following eutectic solidification. Structural studies of samples with initial Au thickness of 1,000 {angstrom}/side appear to correspond with the phonon transmission study.

  2. The Proposed Majorana 76Ge Double-Beta Decay Experiment

    SciTech Connect (OSTI)

    Aalseth, Craig E.; Anderson, Dale N.; Arthur, Richard J.; Avignone, Frank T.; Baktash, Cryus; Ball, Thedore; Barabash, Alexander S.; Bertrand, F.; Brodzinski, Ronald L.; Brudanin, V.; Bugg, William; Champagne, A. E.; Chan, Yuen-Dat; Cianciolo, Thomas V.; Collar, J. I.; Creswick, R. W.; Descovich, M.; Di Marco, Marie; Doe, P. J.; Dunham, Glen C.; Efremenko, Yuri; Egerov, V.; Ejiri, H.; Elliott, Steven R.; Emanuel, A.; Fallon, Paul; Farach, H. A.; Gaitskell, R. J.; Gehman, Victor; Grzywacz, Robert; Hallin, A.; Hazma, R.; Henning, R.; Hime, Andrew; Hossbach, Todd W.; Jordan, David V.; Kazkaz, K.; Kephart, Jeremy; King, G. S.; Kochetov, Oleg; Konovalov, S.; Kouzes, Richard T.; Lesko, Kevin; Luke, P.; Luzum, M.; Macchiavelli, A. O.; McDonald, A.; Mei, Dongming; Miley, Harry S.; Mills, G. B.; Mokhtarani, A.; Nomachi, Masaharu; Orrell, John L.; Palms, John M.; Poon, Alan; Radford, D. C.; Reeves, James H.; Robertson, R. G. H.; Runkle, Robert C.; Rykaczewski, Krzysztof P.; Saburov, Konstantin; Sandukovsky, Viatcheslav; Sonnenschein, Andrew; Tornow, W.; Tull, C.; van de Water, R. G.; Vanushin, Igor; Vetter, Kai; Warner, Ray A.; Wilkerson, John F.; Wouters, Jan M.; Young , A. R.; Yumatov, V.

    2005-01-01

    The proposed Majorana experiment is based on an array of segmented intrinsic Ge detectors with a total mass of 500 kg of Ge isotopically enriched to 86% in 76Ge. Background reduction will be accomplished by: material selection, detector segmentation, pulse shape analysis, electro-formation of copper parts, and granularity of detector spacing. The predicted experimental sensitivity for measurement of the neutrinoless double-beta decay mode of 76Ge, over a data acquisition period of 5000 kg•y, is ~ 4?1027 y.

  3. GE funds initiative to support STEM initiatives in Oklahoma ...

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

    investment in Oklahoma reflects GE's commitment to skills development for the future. "Growth and development go hand-in-hand with educational excellence, strength in science,...

  4. CMC technology revolutionary for aviation, power | GE Global...

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

    in new window) Novel CMC technology revolutionizes aircraft engines, turbines CMCs - Ceramic Matrix Composites - are a revolutionary material invented by GE scientists that offer...

  5. Heteroepitaxial Ge-on-Si by DC magnetron sputtering

    SciTech Connect (OSTI)

    Steglich, Martin; Schrempel, Frank; Füchsel, Kevin; Kley, Ernst-Bernhard; Patzig, Christian; Berthold, Lutz; Höche, Thomas; Tünnermann, Andreas; Fraunhofer Institute for Applied Optics and Precision Engineering IOF, Albert-Einstein-Str. 7, 07745 Jena

    2013-07-15

    The growth of Ge on Si(100) by DC Magnetron Sputtering at various temperatures is studied by Spectroscopic Ellipsometry and Transmission Electron Microscopy. Smooth heteroepitaxial Ge films are prepared at relatively low temperatures of 380°C. Typical Stransky-Krastanov growth is observed at 410°C. At lower temperatures (320°C), films are essentially amorphous with isolated nanocrystallites at the Si-Ge interface. A minor oxygen contamination at the interface, developing after ex-situ oxide removal, is not seen to hinder epitaxy. Compensation of dislocation-induced acceptors in Ge by sputtering from n-doped targets is proposed.

  6. Construction progresses at GE's Oil & Gas Technology Center ...

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

    Home > Impact > Construction progressing at GE's newest research center, the Oil & Gas Technology Center in Oklahoma City Click to email this to a friend (Opens in new window)...

  7. RADIATION DAMAGE RESISTANCE OF REVERSE ELECTRODE GE COAXIAL DETECTORS

    E-Print Network [OSTI]

    Pehl, Richard H.

    2011-01-01

    Parker, "Radiation Damage of Germanium Detectors", Bull. Am.to radiation damage between the two detectors was clearlyRADIATION DAMAGE RESISTANCE OF REVERSE ELECTRODE GE COAXIAL DETECTORS

  8. GE China Technology Center Wins Top 12 Most Innovative Practices...

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

    to our local markets and innovating technologies to meet the most urgent needs of Chinese society. Additionally, GE teams up with local customers to jointly develop innovative...

  9. The Wizard of Schenectady: Charles Proteus Steinmetz | GE Global...

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

    week the Smithsonian's "Past Imperfect" blog highlighted a man near and dear to the heart of GE Global Research, Charles Proteus Steinmetz. The article paints a really...

  10. Big Data and Analytics at Work | GE Global Research

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

    time analytics is required At GE we keep pace with these trends via the Industrial Internet, a highly connected ecosystem of intelligent machines, advanced analytics and people...

  11. A Sneak Peek Into Santa's Smarter Sleigh | GE Global Research

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

    legs a break. - An upgraded sleigh frame made from GE's high temperature Ceramic Matrix Composites (CMCs). The CMCs can withstand the heat of entry and reentry in earth's...

  12. Titan propels GE wind turbine research into new territory | ornl...

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

    Titan propels GE wind turbine research into new territory January 17, 2014 The amount of global electricity supplied by wind, the world's fastest growing energy source, is expected...

  13. Thoughts From the 2012 Whitney Software Symposium | GE Global...

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

    Big Data, Modeling and Simulation, High Performance Computing and the Industrial Internet as key technological enablers of GE's Software initiatives. We enjoyed speakers from...

  14. EEDP and Other Leadership Programs | GE Global Research

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

    Ready to dive in? Apply for the program. GE Software Leadership Program The rise of the Industrial Internet requires a new breed of talent and organizational capability. New...

  15. Impact ionization of excitons in Ge/Si structures with Ge quantum dots grown on the oxidized Si(100) surfaces

    SciTech Connect (OSTI)

    Shklyaev, A. A. [A. V. Rzhanov Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Shegai, O. A. [A. V. Rzhanov Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090 (Russian Federation); Nakamura, Y. [Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan); Ichikawa, M. [Department of Applied Physics, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656 (Japan)

    2014-05-28

    Photoconductivity (PC) of Si/Ge structures with Ge quantum dots (QDs) grown on the Si(100) surfaces covered with the ultrathin, about 0.3–0.5?nm thick, SiO{sub 2} films is studied as a function of the interband light intensity under various lateral voltages. The structures exhibit PC with steps and a step with a peak at the step edge for low- and high-temperature grown structures, respectively. These PC features are associated with the impact ionization of QD-related excitons. The PC at step edges increases by several orders of magnitude for a certain value which is governed by the balance between rates of photo-generation, recombination, and impact ionization of excitons. The electron localization deeper in Si from the Ge QD layer in conjunction with a narrow binding-energy distribution of excitons is suggested to be the main reason that provides the sharpness of PC steps. The PC appears to be very sensitive to the impact ionization and QD preparation conditions. This allows revealing the specific characteristics of QD structures, related to their electronic and structural properties.

  16. Structural and optical properties of GaAs-based heterostructures with Ge and Ge/InGaAs quantum wells

    SciTech Connect (OSTI)

    Aleshkin, V. Ya.; Dubinov, A. A., E-mail: sanya@ipm.sci-nnov.ru; Drozdov, M. N. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation); Zvonkov, B. N. [Nizhni Novgorod State University, Research Physical Technical Institute (Russian Federation); Kudryavtsev, K. E.; Tonkikh, A. A.; Yablonskiy, A. N. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation); Werner, P. [Max Planck Institute of Microstructure Physics (Germany)

    2013-05-15

    GaAs-based heterostructures with Ge and Ge/InGaAs quantum wells are grown by laser-assisted sputtering. Structural and optical studies of the heterostructures are carried out. A broad photoluminescence line is observed in the wavelength range from 1300 to 1650 nm. The line corresponds to indirect transitions in the momentum space of the Ge quantum wells and to transitions between the In{sub 0.28}Ga{sub 0.72}As and Ge layers, indirect in coordinate space, but direct in momentum space.

  17. Microgravity and Vision in Astronauts | GE Global Research

    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 Administration wouldMass map shines light on dark matterEnergyPublicatonsSubstancesproteinGE Researchers Study

  18. Shell model description of Ge isotopes

    E-Print Network [OSTI]

    J. G. Hirsch; P. C. Srivastava

    2012-04-12

    A shell model study of the low energy region of the spectra in Ge isotopes for $38\\leq N\\leq 50$ is presented, analyzing the excitation energies, quadrupole moments, $B(E2)$ values and occupation numbers. The theoretical results have been compared with the available experimental data. The shell model calculations have been performed employing three different effective interactions and valence spaces.We have used two effective shell model interactions, JUN45 and jj44b, for the valence space $f_{5/2} \\, p \\,g_{9/2}$ without truncation. To include the proton subshell $f_{7/2}$ in valence space we have employed the $fpg$ effective interaction due to Sorlin {\\it et al.}, with $^{48}$Ca as a core and a truncation in the number of excited particles.

  19. 3 GeV Injector Design Handbook

    SciTech Connect (OSTI)

    Wiedemann, H.; /SLAC, SSRL

    2009-12-16

    This Design Handbook is intended to be the main reference book for the specifications of the 3 GeV SPEAR booster synchrotron project. It is intended to be a consistent description of the project including design criteria, key technical specifications as well as current design approaches. Since a project is not complete till it's complete changes and modifications of early conceptual designs must be expected during the duration of the construction. Therefore, this Design Handbook is issued as a loose leaf binder so that individual sections can be replaced as needed. Each page will be dated to ease identification with respect to latest revisions. At the end of the project this Design Handbook will have become the 'as built' reference book of the injector for operations and maintenance personnel.

  20. Nucleon Resonances Near 2 GeV

    E-Print Network [OSTI]

    He, Jun

    2015-01-01

    The nucleon resonances near 2 GeV are investigated through the $\\Sigma$(1385) and $\\Lambda(1520)$ photoproductions within a Regge-plus-resonance approach based on the new experimental data released by the CLAS Collaboration. The $\\Delta(2000)$ and the $N(2120)$ are found essential to reproduce the experimental data and should be assigned as second $[\\Delta 5/2^+]$ and third $[N3/2^-]$ in the constituent quark model, respectively. A calculation of the binding energy and decay pattern supports that the $N(1875)$, which is listed in the PDG as the third $N3/2^-$ nucleon resonance instead of the $N(2120)$, is from the $\\Sigma(1385)K$ interaction rather than a three quark state.

  1. Nanostructure and infrared photoluminescence of nanocrystalline Ge formed by reduction of Si0.75Ge0.25O2 Si0.75Ge0.25 using various H2 pressures

    E-Print Network [OSTI]

    Nanostructure and infrared photoluminescence of nanocrystalline Ge formed by reduction of Si0.75Ge0.25O2 ÕSi0.75Ge0.25 using various H2 pressures Gianni Taraschi,a) Sajan Saini, Wendy W. Fan, Lionel C Ge in SiO2 was synthesized by the reduction of Si0.75Ge0.25O2 with H2 , at various annealing

  2. Band-engineered Ge-on-Si lasers

    E-Print Network [OSTI]

    Liu, Jifeng

    We report optically-pumped Ge-on-Si lasers with direct gap emission near 1600 nm at room temperature. The Ge-on-Si material was band-engineered by tensile strain and n-type doping to compensate the energy difference between ...

  3. Ge#ng Started on HokieSpeed

    E-Print Network [OSTI]

    Crawford, T. Daniel

    Ge#ng Started on HokieSpeed Advanced Research Computing #12;Advanced Research Compu:ng;Advanced Research Compu:ng Important Login Informa:on · Account sheets provide login Compu:ng Ge#ng Started Steps 1. Sheet distributed provides your training account

  4. Excess carrier lifetimes in Ge layers on Si

    SciTech Connect (OSTI)

    Geiger, R., E-mail: richard.geiger@psi.ch, E-mail: hans.sigg@psi.ch; Sigg, H., E-mail: richard.geiger@psi.ch, E-mail: hans.sigg@psi.ch [Laboratory for Micro- and Nanotechnology, Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Frigerio, J.; Chrastina, D.; Isella, G. [L-NESS, Dipartimento di Fisica del Politecnico di Milano, Via Anzani 42, 22100 Como (Italy); Süess, M. J. [Laboratory for Micro- and Nanotechnology, Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Laboratory for Nanometallurgy, Department of Materials Science, ETH Zurich, 8093 Zurich (Switzerland); Scientific Center for Optical and Electron Microscopy (SCOPEM), ETH Zurich, 8093 Zurich (Switzerland); Spolenak, R. [Laboratory for Nanometallurgy, Department of Materials Science, ETH Zurich, 8093 Zurich (Switzerland); Faist, J. [Institute for Quantum Electronics, ETH Zurich, 8093 Zurich (Switzerland)

    2014-02-10

    The excess charge carrier lifetimes in Ge layers grown on Si or germanium-on-insulator are measured by synchrotron based pump-probe transmission spectroscopy. We observe that the lifetimes do not strongly depend on growth parameters and annealing procedure, but on the doping profile. The defect layer at the Ge/Si interface is found to be the main non-radiative recombination channel. Therefore, the longest lifetimes in Ge/Si (2.6?ns) are achieved in sufficiently thick Ge layers with a built-in field, which repels electrons from the Ge/Si interface. Longer lifetimes (5.3?ns) are obtained in overgrown germanium-on-insulator due to the absence of the defective interface.

  5. The thermoelectric properties of Ge/SiGe modulation doped superlattices A. Samarelli, L. Ferre Llin, S. Cecchi, J. Frigerio, T. Etzelstorfer et al.

    E-Print Network [OSTI]

    Hague, Jim

    The thermoelectric properties of Ge/SiGe modulation doped superlattices A. Samarelli, L. Ferre Llin thermoelectric properties of Ge/SiGe modulation doped superlattices A. Samarelli,1 L. Ferre Llin,1 S. Cecchi,2 J June 2013) The thermoelectric and physical properties of superlattices consisting of modulation doped

  6. On atomic structure of Ge huts growing on the Ge/Si(001) wetting layer

    SciTech Connect (OSTI)

    Arapkina, Larisa V.; Yuryev, Vladimir A. [A. M. Prokhorov General Physics Institute of the Russian Academy of Sciences, 38 Vavilov Street, Moscow, 119991 (Russian Federation)] [A. M. Prokhorov General Physics Institute of the Russian Academy of Sciences, 38 Vavilov Street, Moscow, 119991 (Russian Federation)

    2013-09-14

    Structural models of growing Ge hut clusters—pyramids and wedges—are proposed on the basis of data of recent STM investigations of nucleation and growth of Ge huts on the Si(001) surface in the process of molecular beam epitaxy. It is shown that extension of a hut base along <110> directions goes non-uniformly during the cluster growth regardless of its shape. Growing pyramids, starting from the second monolayer, pass through cyclic formation of slightly asymmetrical and symmetrical clusters, with symmetrical ones appearing after addition of every fourth monolayer. We suppose that pyramids of symmetrical configurations composed by 2, 6, 10, etc., monolayers over the wetting layer are more stable than asymmetrical ones. This might explain less stability of pyramids in comparison with wedges in dense arrays forming at low temperatures of Ge deposition. Possible nucleation processes of pyramids and wedges on wetting layer patches from identical embryos composed by 8 dimers through formation of 1 monolayer high 16-dimer nuclei different only in their symmetry is discussed. Schematics of these processes are presented. It is concluded from precise STM measurements that top layers of wetting layer patches are relaxed when huts nucleate on them.

  7. Ratio of jet cross sections at root s=630 GeV and 1800 GeV

    E-Print Network [OSTI]

    Baringer, Philip S.; Bean, Alice; Coppage, Don; Hebert, C.

    2001-03-01

    The DO Collaboration has measured the inclusive jet cross section in (p) over barp collisions at roots = 630 GeV. The results for pseudorapidities \\ eta \\ < 0.5 are combined with our previous results at roots = 1800 GeV ...

  8. Ion Implanted Ge:B Far Infrard Blocked Impurity Band Detectors

    E-Print Network [OSTI]

    Beeman, J.W.; Goyal, S.; Reichertz, L.A.; Haller, E.E.

    2008-01-01

    +16 1.E+15 1.E+14 Depth into Ge Crystal Surface (Å) Figure 5devices does not match that of Ge:Ga photoconductors, whichimplants or stacking devices) Ge IBIB detectors will reach

  9. ALFVEN-WAVE OSCILLATIONS IN A SPHERE, WITH APPLICATIONS TO ELECTRON-HOLE DROPS IN Ge

    E-Print Network [OSTI]

    Markiewicz, R.S.

    2011-01-01

    Rev. B 13,4626 (1976). For Ge(4:2) m is the average of thediscussed for EHD in unstressed Ge (B II )TO ELECI'RON-OOLE DROPS IN Ge R. S. Markiewicz January 1978

  10. NUCLEATION PHENOMENA IN THE FORMATION OF ELECTRON-HOLE DROPS IN Ge

    E-Print Network [OSTI]

    Westervelt, R.M.

    2010-01-01

    lO cjl(K) Symbol erg cm ) Ge - 0.064 T2 Ref. x x Si Ref. T2constructed the ultra-sensitive Ge photodetector which wasand method of mounting. The Ge sample is electrically and

  11. Photo-oxidation of Ge Nanocrystals: Kinetic Measurements by In Situ Raman Spectroscopy

    E-Print Network [OSTI]

    2008-01-01

    Photo-oxidation of Ge Nanocrystals: Kinetic Measurements byBerkeley, CA, 94720 ABSTRACT Ge nanocrystals are formed inthe Raman spectra of the Ge nanocrystals in-situ. The

  12. Ferromagnetism in Mn-Implanted Epitaxially Grown Ge on Si(100)

    E-Print Network [OSTI]

    Guchhait, S.

    2011-01-01

    segregation in Mn-doped Ge”, Journal of Applied Physics 101,Room-temperature ferromagnetism in Ge 1-x Mn x nanowires”,BC high-?/metal gate Ge/C alloy pMOSFETs fabricated directly

  13. Origins of low resistivity and Ge donor level in Ge ion-implanted ZnO bulk single crystals

    SciTech Connect (OSTI)

    Kamioka, K.; Oga, T.; Izawa, Y.; Kuriyama, K. [College of Engineering and Research Center of Ion Beam Technology, Hosei University Koganei, Tokyo 184-8584 (Japan); Kushida, K. [Departments of Arts and Sciences, Osaka Kyoiku University Kashiwara, Osaka 582-8582 (Japan)

    2013-12-04

    The energy level of Ge in Ge-ion implanted ZnO single crystals is studied by Hall-effect and photoluminescence (PL) methods. The variations in resistivity from ?10{sup 3} ?cm for un-implanted samples to ?10{sup ?2} ?cm for as-implanted ones are observed. The resistivity is further decreased to ?10{sup ?3} ?cm by annealing. The origins of the low resistivity are attributed to both the zinc interstitial (Zn{sub i}) related defects and the electrical activated Ge donor. An activation energy of Ge donors estimated from the temperature dependence of carrier concentration is 102 meV. In PL studies, the new peak at 372 nm (3.33 eV) related to the Ge donor is observed in 1000 °C annealed samples.

  14. GeO{sub 2}/Ge structure submitted to annealing in deuterium: Incorporation pathways and associated oxide modifications

    SciTech Connect (OSTI)

    Bom, N. M.; Soares, G. V.; Hartmann, S.; Bordin, A.; Radtke, C.

    2014-10-06

    Deuterium (D) incorporation in GeO{sub 2}/Ge structures following D{sub 2} annealing was investigated. Higher D concentrations were obtained for GeO{sub 2}/Ge samples in comparison to their SiO{sub 2}/Si counterparts annealed in the same conditions. Oxygen vacancies produced during the annealing step in D{sub 2} constitute defect sites for D incorporation, analogous to defects at the SiO{sub 2}/Si interfacial region. Besides D incorporation, volatilization of the oxide layer is also observed as a consequence of D{sub 2} annealing, especially in the high temperature regime of the present study (>450?°C). In parallel to this volatilization, the stoichiometry and chemical structure of remnant oxide are modified as well. These results evidence the broader impact of forming gas annealing in dielectric/Ge structures with respect to SiO{sub 2}/Si counterparts.

  15. Transient and temperature-dependent phenomena in Ge:Be and Ge:Zn far infrared photoconductors

    SciTech Connect (OSTI)

    Haegel, N.M.

    1985-11-01

    An experimental study of the transient and temperature-dependent behavior of Ge:Be and Ge:Zn photoconductors has been performed under the low background photon flux conditions (p dot approx. = 10/sup 8/ photons/second) typical of astronomy and astrophysics applications. The responsivity of Ge:Be and Ge:Zn detectors is strongly temperature-dependent in closely compensated material, and the effect of compensation on free carrier lifetime in Ge:Be has been measured using the photo-Hall effect technique. Closely compensated material has been obtained by controlling the concentration of novel hydrogen-related shallow acceptor complexes, A(Be,H) and A(Zn,H), which exist in doped crystals grown under a H/sub 2/ atmosphere. A review of selection criteria for multilevel materials for optimum photoconductor performance is included. 55 refs., 47 figs.

  16. Ion beam synthesis of SiGe alloy layers

    SciTech Connect (OSTI)

    Im, Seongil

    1994-05-01

    Procedures required for minimizing structural defects generated during ion beam synthesis of SiGe alloy layers were studied. Synthesis of 200 mm SiGe alloy layers by implantation of 120-keV Ge ions into <100> oriented Si wafers yielded various Ge peak concentrations after the following doses, 2{times}10{sup 16}cm{sup {minus}2}, 3{times}10{sup 16}cm{sup {minus}2} (mid), and 5{times}10{sup 16}cm{sup {minus}2} (high). Following implantation, solid phase epitaxial (SPE) annealing in ambient N2 at 800C for 1 hr. resulted in only slight redistribution of the Ge. Two kinds of extended defects were observed in alloy layers over 3{times}l0{sup 16}cm{sup {minus}2}cm dose at room temperature (RT): end-of-range (EOR) dislocation loops and strain-induced stacking faults. Density of EOR dislocation loops was much lower in alloys produced by 77K implantation than by RT implantation. Decreasing the dose to obtain 5 at% peak Ge concentration prevents strain relaxation, while those SPE layers with more than 7 at% Ge peak show high densities of misfit- induced stacking faults. Sequential implantation of C following high dose Ge implantation (12 at% Ge peak concentration in layer) brought about a remarkable decrease in density of misfit-induced stacking faults. For peak implanted C > 0.55 at%, stacking fault generation in the epitaxial layer was suppressed, owing to strain compensation by C atoms in the SiGe lattice. A SiGe alloy layer with 0.9 at% C peak concentration under a 12 at% Ge peak exhibited the best microstructure. Results indicate that optimum Ge/C ratio for strain compensation is between 11 and 22. The interface between amorphous and regrown phases (a/c interface) had a dramatic morphology change during its migration to the surface. Initial <100> planar interface decomposes into a <111> faceted interface, changing the growth kinetics; this is associated with strain relaxation by stacking fault formation on (111) planes in the a/c interface.

  17. Atomic geometry of mixed Ge-Si dimers in the initial-stage growth of Ge on Si,,001...2 1 X. Chen* and D. K. Saldin

    E-Print Network [OSTI]

    Saldin, Dilano

    Atomic geometry of mixed Ge-Si dimers in the initial-stage growth of Ge on Si,,001...2 1 X. Chen quantitatively the geometry of mixed Ge-Si dimers on a single domain Si 001 2 1 surface by azimuthal scanning core-level photoelectron diffraction. By analyzing Ge 3d diffraction patterns from Ge/Si 001 at 0.1 ML

  18. GeV Emission from Collisional Magnetized Gamma Ray Bursts

    E-Print Network [OSTI]

    P. Mészáros; M. J. Rees

    2011-04-26

    Magnetic fields may play a dominant role in gamma-ray bursts, and recent observations by the Fermi satellite indicate that GeV radiation, when detected, arrives delayed by seconds from the onset of the MeV component. Motivated by this, we discuss a magnetically dominated jet model where both magnetic dissipation and nuclear collisions are important. We show that, for parameters typical of the observed bursts, such a model involving a realistic jet structure can reproduce the general features of the MeV and a separate GeV radiation component, including the time delay between the two. The model also predicts a multi-GeV neutrino component.

  19. GE Store for Technology is Open for Business | GE Global Research

    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 Room NewsInformation Current HABFESOpportunities Nuclear Physics (NP)aboutRio deCooperation atThe GE

  20. Greatly improved interfacial passivation of in-situ high ? dielectric deposition on freshly grown molecule beam epitaxy Ge epitaxial layer on Ge(100)

    SciTech Connect (OSTI)

    Chu, R. L. [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Liu, Y. C.; Lee, W. C.; Huang, M. L.; Kwo, J., E-mail: raynien@phys.nthu.edu.tw, E-mail: mhong@phys.ntu.edu.tw [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Lin, T. D.; Hong, M., E-mail: raynien@phys.nthu.edu.tw, E-mail: mhong@phys.ntu.edu.tw [Graduate Institute of Applied Physics and Department of Physics, National Taiwan University, Taipei 10617, Taiwan (China); Pi, T. W. [National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan (China)

    2014-05-19

    A high-quality high-?/Ge interface has been achieved by combining molecule beam epitaxy grown Ge epitaxial layer and in-situ deposited high ? dielectric. The employment of Ge epitaxial layer has sucessfully buried and/or removed the residue of unfavorable carbon and native oxides on the chemically cleaned and ultra-high vacuum annealed Ge(100) wafer surface, as studied using angle-resolved x-ray photoelectron spectroscopy. Moreover, the scanning tunneling microscopy analyses showed the significant improvements in Ge surface roughness from 3.5?Å to 1?Å with the epi-layer growth. Thus, chemically cleaner, atomically more ordered, and morphologically smoother Ge surfaces were obtained for the subsquent deposition of high ? dielectrics, comparing with those substrates without Ge epi-layer. The capacitance-voltage (C-V) characteristics and low extracted interfacial trap density (D{sub it}) reveal the improved high-?/Ge interface using the Ge epi-layer approach.

  1. Atomic layer-by-layer oxidation of Ge (100) and (111) surfaces by plasma post oxidation of Al{sub 2}O{sub 3}/Ge structures

    SciTech Connect (OSTI)

    Zhang, Rui [School of Engineering, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-8656 (Japan) [School of Engineering, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-8656 (Japan); School of Electronic Science and Engineering, Nanjing University, 22 Hankou Road, Nanjing 210093 (China); Huang, Po-Chin; Lin, Ju-Chin; Takenaka, Mitsuru; Takagi, Shinichi [School of Engineering, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-8656 (Japan)] [School of Engineering, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-8656 (Japan)

    2013-02-25

    The ultrathin GeO{sub x}/Ge interfaces formed on Ge (100) and (111) surfaces by applying plasma post oxidation to thin Al{sub 2}O{sub 3}/Ge structures are characterized in detail using X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy. It is found that the XPS signals assigned to Ge 1+ and the 2+ states in the GeO{sub x} layers by post plasma oxidation have oscillating behaviors on Ge (100) surfaces in a period of {approx}0.3 nm with an increase in the GeO{sub x} thickness. Additionally, the oscillations of the signals assigned to Ge 1+ and 2+ states show opposite phase to each other. The similar oscillation behaviors are also confirmed on Ge (111) surfaces for Ge 1+ and 3+ states in a period of {approx}0.5 nm. These phenomena can be strongly regarded as an evidence of the atomic layer-by-layer oxidation of GeO{sub x}/Ge interfaces on Ge (100) and (111) surfaces.

  2. Investigations of segregation phenomena in highly strained Mn-doped Ge wetting layers and Ge quantum dots embedded in silicon

    SciTech Connect (OSTI)

    Prestat, E., E-mail: eric.prestat@gmail.com; Porret, C.; Favre-Nicolin, V.; Tainoff, D.; Boukhari, M.; Bayle-Guillemaud, P.; Jamet, M.; Barski, A., E-mail: andre.barski@cea.com [INAC, SP2M, CEA and Université Joseph Fourier, 17 rue des Martyrs, 38054 Grenoble (France)

    2014-03-10

    In this Letter, we investigate manganese diffusion and the formation of Mn precipitates in highly strained, few monolayer thick, Mn-doped Ge wetting layers and nanometric size Ge quantum dot heterostructures embedded in silicon. We show that in this Ge(Mn)/Si system manganese always precipitates and that the size and the position of Mn clusters (precipitates) depend on the growth temperature. At high growth temperature, manganese strongly diffuses from germanium to silicon, whereas decreasing the growth temperature reduces the manganese diffusion. In the germanium quantum dots layers, Mn precipitates are detected, not only in partially relaxed quantum dots but also in fully strained germanium wetting layers between the dots.

  3. Germanium subcells for multijunction GaInP/GaInAs/Ge solar cells

    SciTech Connect (OSTI)

    Kalyuzhnyy, N. A.; Gudovskikh, A. S.; Evstropov, V. V.; Lantratov, V. M.; Mintairov, S. A.; Timoshina, N. Kh.; Shvarts, M. Z.; Andreev, V. M.

    2010-11-15

    Photovoltaic converters based on n-GaInP/n-p-Ge heterostructures grown by the OMVPE under different conditions of formation of the p-n junction are studied. The heterostructures are intended for use as narrow-gap subcells of the GaInP/GaInAs/Ge three-junction solar cells. It is shown that, in Ge p-tn junctions, along with the diffusion mechanism, the tunneling mechanism of the current flow exists; therefore, the two-diode electrical equivalent circuit of the Ge p-n junction is used. The diode parameters are determined for both mechanisms from the analysis of both dark and 'light' current-voltage dependences. It is shown that the elimination of the component of the tunneling current allows one to increase the efficiency of the Ge subcell by {approx}1% with conversion of nonconcentrated solar radiation. The influence of the tunneling current on the efficiency of the Ge-based devices can be in practice reduced to zero at photogenerated current density of {approx}1.5 A/cm{sup 2} due to the use of the concentrated solar radiation.

  4. Direct band gap narrowing in highly doped Ge

    E-Print Network [OSTI]

    Han, Zhaohong

    Direct band gap narrowing in highly doped n-type Ge is observed through photoluminescence measurements by determining the spectrum peak shift. A linear relationship between the direct band gap emission and carrier concentration ...

  5. Growth strategies to control tapering in Ge nanowires

    SciTech Connect (OSTI)

    Periwal, P.; Baron, T., E-mail: thierry.baron@cea.fr; Salem, B.; Bassani, F. [Laboratoire des Technologies de la Microelectronique (LTM), UMR 5129 CNRS-UJF, CEA Grenoble, 17 Rue des Martyrs, 38054 Grenoble (France); Gentile, P. [SiNaPs Laboratory SP2M, UMR-E, CEA/UJF-Grenoble 1, INAC, 38054 Grenoble (France)

    2014-04-01

    We report the effect of PH{sub 3} on the morphology of Au catalyzed Ge nanowires (NWs). Ge NWs were grown on Si (111) substrate at 400?°C in the presence of PH{sub 3}, using vapor-liquid-solid method by chemical vapor deposition. We show that high PH{sub 3}/GeH{sub 4} ratio causes passivation at NW surface. At high PH{sub 3} concentration phosphorous atoms attach itself on NW surface and form a self-protection coating that prevents conformal growth and leads to taper free nanostructures. However, in case of low PH{sub 3} flux the combination of axial and radial growth mechanism occurs resulting in conical structure. We have also investigated axial PH{sub 3}-intrinsic junctions in Ge NWs. The unusual NW shape is attributed to a combination of catalyzed, uncatalyzed and diffusion induced growth.

  6. Nanocrystalline Ge Flash Memories: Electrical Characterization and Trap Engineering

    E-Print Network [OSTI]

    Kan, Eric Win Hong

    Conventional floating gate non-volatile memories (NVMs) present critical issues for device scalability beyond the sub-90 nm node, such as gate length and tunnel oxide thickness reduction. Nanocrystalline germanium (nc-Ge) ...

  7. Discovery of Isotopes of Elements with Z $\\ge$ 100

    E-Print Network [OSTI]

    M. Thoennessen

    2012-03-09

    Currently, 163 isotopes of elements with Z $\\ge$ 100 have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  8. Ge-on-Si laser operating at room temperature

    E-Print Network [OSTI]

    Liu, Jifeng

    Monolithic lasers on Si are ideal for high-volume and large-scale electronic–photonic integration. Ge is an interesting candidate owing to its pseudodirect gap properties and compatibility with Si complementary metal oxide ...

  9. GE launches 'STEM empowers OK' initiative in Oklahoma City |...

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

    GE, OCAST and OSSM Partner to Launch "STEM Empowers OK" Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click to share (Opens in new...

  10. "Big Picture" Process Modeling Tools |GE Global Research

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

    Using process modeling tools to attain cost-effective results for GE customers Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click...

  11. ORNL Partners with GE on New Hybrid | ornl.gov

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

    electric storage water heater, positioning GE to be the first company to meet the energy-saving standard. According to DOE, using devices that meet these criteria should save...

  12. Kids Invention: Vision of the Future |GE Global Research

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

    and Bring your Child to Work Day, to student mentoring, teaching in the class room, Invention Convention and Science Day. To take the message nationally, GE teamed up with the...

  13. The Need for Biological Computation System Models | GE Global...

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

    2012.10.09 Hello everyone, I'm Maria Zavodszky and I work in the Computational Biology and Biostatistics Lab at GE Global Research in Niskayuna, New York. This being our...

  14. Demonstration of 2nd Generation Ducted GE "Brillion" Hybrid Water

    E-Print Network [OSTI]

    sharing partners. #12;Project Synopsis Evaluate the performance and demand response (DR) of the Gen II GE/frequency response) in the PNW and nationwide (Lu et al, 2011; Diao et al 2012) The demand response characteristics

  15. Carrier Density Modulation in Ge Heterostructure by Ferroelectric Switching

    SciTech Connect (OSTI)

    Ponath, Patrick; Fredrickson, Kurt; Posadas, Agham B.; Ren, Yuan; Vasudevan, Rama K; Okatan, Mahmut Baris; Jesse, Stephen; Aoki, Toshihiro; McCartney, Martha; Smith, David J; Kalinin, Sergei V; Lai, Keji; Demkov, Alexander A.

    2015-01-01

    The development of nonvolatile logic through direct coupling of spontaneous ferroelectric polarization with semiconductor charge carriers is nontrivial, with many issues, including epitaxial ferroelectric growth, demonstration of ferroelectric switching, and measurable semiconductor modulation. Here we report a true ferroelectric field effect carrier density modulation in an underlying Ge(001) substrate by switching of the ferroelectric polarization in the epitaxial c-axis-oriented BaTiO3 (BTO) grown by molecular beam epitaxy (MBE) on Ge. Using density functional theory, we demonstrate that switching of BTO polarization results in a large electric potential change in Ge. Aberration-corrected electron microscopy confirms the interface sharpness, and BTO tetragonality. Electron-energy-loss spectroscopy (EELS) indicates the absence of any low permittivity interlayer at the interface with Ge. Using piezoelectric force microscopy (PFM), we confirm the presence of fully switchable, stable ferroelectric polarization in BTO that appears to be single domain. Using microwave impedance microscopy (MIM), we clearly demonstrate a ferroelectric field effect.

  16. Technology makes reds "pop" in LED displays | GE Global Research

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

    Reveal and Energy Smart consumer brands, and Evolve(tm), GTx(tm), Immersion(tm), Infusion(tm), Lumination(tm), Albeo(tm) and Tetra commercial brands, all trademarks of GE....

  17. 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

  18. High-efficiency GaAs/Ge monolithic tandem solar cells

    SciTech Connect (OSTI)

    Tobin, S.P.; Vernon, S.M.; Bajgar, C.; Haven, V.E.; Geoffroy, L.M.; Lillington, D.R.

    1988-05-01

    High photovoltaic efficiency and light weight are important criteria for spacecraft power applications. Present GaAs cells are approaching their efficiency limits, but are not efficient or light enough for future needs. The authors have investigated tandem cells of GaAs grown by MOCVD on thin Ge to address both higher efficiency and reduced weight. GaAs/Ge monolithic tandem cells of 4-cm/sup 2/ area have been produced with independently verified efficiencies up to 21.7 percent (AMO, one sun, 25/sup 0/C, total area). Under AM1.5 Global conditions, efficiencies are up to 24.3 percent. These are the highest one-sun efficiencies reported for GaAs/Ge cells, and the highest efficiency for a two-terminal monolithic tandem cell.

  19. GE & AE Extension Request Form, Version 7, Feb 2013, JC Program Change

    E-Print Network [OSTI]

    Escher, Christine

    GE & AE Extension Request Form, Version 7, Feb 2013, JC Program Change Pathway Today's Date to General English. How many sessions of GE do you wish to request? 1 2 3 4 (GE sessions are 5 weeks) How many GE hours do you wish to take? 21 hours 27 hours OR ____ I am a Pathway student, and I would like

  20. College of Engineering Partner Schools Australia Melbourne University, Melbourne GE3*

    E-Print Network [OSTI]

    Lee, Tonghun

    College of Engineering Partner Schools Australia Melbourne University, Melbourne ­ GE3* University of New South Wales, New South Wales ­ GE3* Austria Technical University of Vienna, Vienna - GE3* Chile Universidad del Bio Bio, Concepcion China Xiamen University, Xiamen ­ GE3* Denmark Aalborg University, Aalborg

  1. On the Comparison of Fisher Information of the Weibull and GE Distributions

    E-Print Network [OSTI]

    Kundu, Debasis

    On the Comparison of Fisher Information of the Weibull and GE Distributions Rameshwar D. Gupta exponen- tial (GE) and Weibull distributions for complete and Type-I censored observations. Fisher is much more than the GE distribution. We compute the total information of the Weibull and GE

  2. GE Hosts Visit by DOE to Kick Off High-Efficiency GeneratorDevelopment Program

    E-Print Network [OSTI]

    history of working with the DOE on critical energy programs. Jon Ebacher, Vice President of GE PowerGE Hosts Visit by DOE to Kick Off High-Efficiency GeneratorDevelopment Program Technology Expected of Energy (DOE) recently met with representatives of GE Power Systems and the GE Global Research Center

  3. Orange-green emission from porous Si coated with Ge films: The role of Ge-related defects

    E-Print Network [OSTI]

    Chen, Haydn H.

    Orange-green emission from porous Si coated with Ge films: The role of Ge-related defects X. L. Wua. A new orange-green PL band, centered at 2.25 eV, was observed with full-width at half-maximum of 0.1 e coated, the new PL band remains unchanged in peak energy but drops abruptly in intensity. Spectral

  4. 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.

  5. Strain-induced self-assembly of Ge nanodashes, nanodumbbells, and dot chains on Si(001)

    SciTech Connect (OSTI)

    Zhang, J. J. [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, 01069 Dresden (Germany) [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, 01069 Dresden (Germany); Centre for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052 (Australia); Schmidt, O. G. [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, 01069 Dresden (Germany) [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, 01069 Dresden (Germany); Center for Advancing Electronics Dresden, TU Dresden (Germany)

    2013-09-30

    We investigate the growth of self-assembled Ge nanostructures on top of embedded Ge nanowires on Si(001) substrates. Ge nanostructures, such as nanodashes, nanodumbbells, and dot chains are observed simply by tuning the growth temperature and thickness of the Si spacer between the Ge layers. The self-assembly process is governed by the surface strain fields generated by the embedded Ge nanowires and is well-described by our theoretical calculations. The catalyst-free and horizontal growth of such Ge nanostructures directly on Si(001) is attractive for investigating exotic transport properties through Si/Ge-based quantum devices.

  6. Direct-bandgap electroluminescence from a horizontal Ge p-i-n ridge waveguide on Si(001) substrate

    SciTech Connect (OSTI)

    Liu, Zhi; Li, Yaming; He, Chao; Li, Chuanbo; Xue, Chunlai; Zuo, Yuhua; Cheng, Buwen Wang, Qiming

    2014-05-12

    Horizontal injection Ge p-i-n ridge waveguide light emitting diodes (LEDs) were fabricated on n{sup ?}-Si(001) substrates by ultrahigh vacuum chemical vapor deposition. The direct-bandgap electroluminescence (EL) of Ge waveguide LEDs under a continuous/pulse electrical pump was studied. The heating effect from a continuous electrical pump was found to significantly enhance the emission of devices. The top surface EL intensity of the Ge waveguide LEDs significantly depended on the position. Most direct-bandgap radiative recombination of Ge p-i-n waveguide LEDs occurred near the N{sup +} region of the junction. This interesting phenomenon could be explained by the carrier distribution in the junction and the pseudo-direct bandgap of Ge.

  7. TEM Study on the Evolution of Ge Nanocrystals in Si Oxide Matrix as a Function of Ge Concentration and the Si Reduction Process

    E-Print Network [OSTI]

    Chew, Han Guan

    Growth and evolution of germanium (Ge) nanocrystals embedded into a silicon oxide (SiO?) system have been studied based on the Ge content of co-sputtered Ge-SiO? films using transmission electron microscopy (TEM) and X-ray ...

  8. Mechanism of the Initial Oxidation of Hydrogen andHalogen Terminated Ge(111) Surfaces in Air

    SciTech Connect (OSTI)

    Sun, Shiyu; /Stanford U., Phys. Dept.; Sun, Yun; Liu, Zhi; Lee, Dong-Ick; Pianetta, Piero; /SLAC, SSRL

    2006-08-23

    The initial stage of the oxidation of Ge(111) surfaces etched by HF, HCl and HBr solutions is systematically studied using synchrotron radiation photoelectron spectroscopy (SR-PES). We perform controlled experiments to differentiate the effects of different oxidation factors. SR-PES results show that both moisture and oxygen contribute to the oxidation of the surfaces; however, they play different roles in the oxidation process. Moisture effectively replaces the hydrogen and halogen termination layers with hydroxyl (OH), but hardly oxidizes the surfaces further. On the other hand, dry oxygen does not replace the termination layers, but breaks the Ge-Ge back bonds and oxidizes the substrates with the aid of moisture. In addition, room light enhances the oxidation rate significantly.

  9. The 6 GeV TMD Program at Jefferson Lab

    SciTech Connect (OSTI)

    Puckett, Andrew J.

    2015-01-01

    The study of the transverse momentum dependent parton distributions (TMDs) of the nucleon in semi-inclusive deep-inelastic scattering (SIDIS) has emerged as one of the major physics motivations driving the experimental program using the upgraded 11 GeV electron beam at Jefferson Lab’s Continuous Electron Beam Accelerator Facility (CEBAF). The accelerator construction phase of the CEBAF upgrade is essentially complete and commissioning of the accelerator has begun as of April, 2014. As the new era of CEBAF operations begins, it is appropriate to review the body of published and forthcoming results on TMDs from the 6 GeV era of CEBAF operations, discuss what has been learned, and discuss the key challenges and opportunities for the 11 GeV SIDIS program of CEBAF.

  10. Effect of mixed Ge/Si cross-linking on the physical properties of amorphous Ge-Si-Te networks

    SciTech Connect (OSTI)

    Gunasekera, K.; Boolchand, P. [School of Electronics and Computing Systems, College of Engineering and Applied Science, University of Cincinnati, Cincinnati, Ohio 45221-0030 (United States); Micoulaut, M., E-mail: mmi@lptl.jussieu.fr [Laboratoire de Physique Théorique de la Matière Condensée, Université Pierre et Marie Curie, 4 Place Jussieu, F-75252 Paris Cedex 05 (France)

    2014-04-28

    Amorphous Ge{sub x}Si{sub x}Te{sub 1?2x} glasses are studied as a function of composition by a combination of experimental and theoretical methods, allowing for a full description of the network structure in relationship with physico-chemical properties. Calorimetric and thermal measurements reveal that such glasses display an anomalous behavior across a range of compositions x{sub c1}=7.5% and Ge, Si) are increased. The structural manifestation of these anomalies is understood from ?{sup 119}Sn Mössbauer spectroscopy and First Principles Molecular Dynamics at selected compositions (Ge{sub 20}Te{sub 80}, Si{sub 20}Te{sub 80}, and Ge{sub 10}Si{sub 10}Te{sub 80}). The numerical models reveal the quite different roles played by the modifier or network cross-linker Ge or Si atoms, Si being more tetrahedral in sp{sup 3} geometry, whereas Mössbauer spectroscopy shows that the nature of chemical bonding is dramatically changed around x??8%. The precise evolution of the local structure and chemical bonding ultimately allows understanding the origin of the intermediate phase in these complex tellurides.

  11. C incorporation in epitaxial Ge1yCy layers grown on Ge,,001...: An ab initio study D. Gall, J. D'Arcy-Gall, and J. E. Greene

    E-Print Network [OSTI]

    Gall, Daniel

    C incorporation in epitaxial Ge1ÀyCy layers grown on Ge,,001...: An ab initio study D. Gall, J. D lattice site configurations in fully coherent Ge1 yCy layers grown on Ge 001 . Calculations using strained configuration involving only one C atom per configura- tion. The bond-centered interstitial and the Ge-C split

  12. Field-induced quantum criticality in YbAgGe

    SciTech Connect (OSTI)

    Bud'ko, S.; Canfield, P.

    2008-01-01

    YbAgGe is one of the very few stoichiometric, Yb-based, heavy fermion materials that exhibit field-induced quantum criticality. We will present an overview of thermodynamic and transport measurements in YbAgGe single crystals. Moderate magnetic field (45-90 kOe, depending on orientation) suppresses long range magnetic order, giving rise to non-Fermi-liquid behavior followed at higher field by a crossover to a heavy Fermi-liquid. Given the more accessible temperature and field scales, a non-Fermi liquid region rather than point for T {yields} 0 K may be detected.

  13. Direct band gap optical emission from Ge islands grown on relaxed Si{sub 0.5}Ge{sub 0.5}/Si (100) substrate

    SciTech Connect (OSTI)

    Aluguri, R.; Manna, S.; Ray, S. K., E-mail: physkr@phy.iitkgp.ernet.in [Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India)

    2014-01-07

    Strained Ge islands have been grown on fully relaxed Si{sub 0.5}Ge{sub 0.5} substrate by pulsed laser ablation technique. The formation of strained Ge islands has been found for film with higher thickness following Stranski–Krastanov growth mechanism. The variation of strain with changing Ge layer thickness has been analyzed using Raman spectroscopy and high-resolution X-ray diffraction techniques. X-ray photoelectron spectra have shown the absence of any Si-Ge intermixing and oxidation of Ge films. A strong no-phonon photoluminescence emission from Ge islands has been observed, showing the superior optical characteristics of the islands grown on relaxed substrate.

  14. 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.

  15. INFLUENCE OF SUBSTRATE OFF-CUT ON THE DEFECT STRUCTURE IN RELAXED GRADED Si-Ge/Si LAYERS

    E-Print Network [OSTI]

    INFLUENCE OF SUBSTRATE OFF-CUT ON THE DEFECT STRUCTURE IN RELAXED GRADED Si-Ge/Si LAYERS SRIKANTH B and Engineering, University of California, Los Angeles, CA 90095. ABSTRACT Relaxed graded Si-Ge/Si layers can of these applications requires a different final Ge concentration in the graded Si-Ge layer. With increasing Ge content

  16. GE & AE Extension Request Form, Version 11, Feb 2013, JC Program Change General English or Academic English

    E-Print Network [OSTI]

    Escher, Christine

    GE & AE Extension Request Form, Version 11, Feb 2013, JC Program Change ­ General English of GE do you wish to request? 1 2 3 4 (GE sessions are 5 weeks) How many GE hours do you wish to take ______________________________________________ Date _________________ #12;GE & AE Extension Request Form, Version 11, Feb 2013, JC Please submit

  17. First observation of temperature dependent lightinduced response of Ge25As10Se65 thin films

    E-Print Network [OSTI]

    Khan, Pritam; Deshpande, Uday; Adarsh, K V

    2015-01-01

    Ge rich ternary chalcogenide glasses (ChG) exhibit photobleaching (PB) when illuminated with bandgap light and such an effect is originating from the combined effect of intrinsic structural changes and photo-oxidation. In a sharp contradict to these previous observations, in this letter, we demonstrate for the first time that Ge rich Ge25As10Se65 ChG thin films exhibit photodarkening (PD) at 20 K and PB at 300 and 420 K for continuous illumination of ~ 3 hours. Strikingly, the temporal evolution of PD/PB show distinct characteristics at the temperatures of illumination and provide valuable information on the light induced structural changes. Further, structure specific far infrared (FIR) absorption measurements give direct evidence of different structural units involved in PD/PB at the contrasting temperatures. By comparing the lightinduced effects in vacuum and air, we conclude that intrinsic structural changes dominate over photo-oxidation in the observed PB in Ge25As10Se65 ChG thin films.

  18. Tropical cyclone energy dispersion under vertical shears Xuyang Ge,1

    E-Print Network [OSTI]

    Li, Tim

    Tropical cyclone energy dispersion under vertical shears Xuyang Ge,1 Tim Li,1,2 and Xiaqiong Zhou1] Tropical cyclone Rossby wave energy dispersion under easterly and westerly vertical shears is investigated, and X. Zhou (2007), Tropical cyclone energy dispersion under vertical shears, Geophys. Res. Lett., 34, L

  19. The JLAB 12 GeV Energy Upgrade of CEBAF

    SciTech Connect (OSTI)

    Harwood, Leigh H.

    2013-12-01

    This presentation should describe the progress of the 12GeV Upgrade of CEBAF at Jefferson Lab. The status of the upgrade should be presented as well as details on the construction, procurement, installation and commissioning of the magnet and SRF components of the upgrade.

  20. Demand Response Performance of GE Hybrid Heat Pump Water Heater

    SciTech Connect (OSTI)

    Widder, Sarah H.; Parker, Graham B.; Petersen, Joseph M.; Baechler, Michael C.

    2013-07-01

    This report describes a project to evaluate and document the DR performance of HPWH as compared to ERWH for two primary types of DR events: peak curtailments and balancing reserves. The experiments were conducted with GE second-generation “Brillion”-enabled GeoSpring hybrid water heaters in the PNNL Lab Homes, with one GE GeoSpring water heater operating in “Standard” electric resistance mode to represent the baseline and one GE GeoSpring water heater operating in “Heat Pump” mode to provide the comparison to heat pump-only demand response. It is expected that “Hybrid” DR performance, which would engage both the heat pump and electric elements, could be interpolated from these two experimental extremes. Signals were sent simultaneously to the two water heaters in the side-by-side PNNL Lab Homes under highly controlled, simulated occupancy conditions. This report presents the results of the evaluation, which documents the demand-response capability of the GE GeoSpring HPWH for peak load reduction and regulation services. The sections describe the experimental protocol and test apparatus used to collect data, present the baselining procedure, discuss the results of the simulated DR events for the HPWH and ERWH, and synthesize key conclusions based on the collected data.

  1. 7-GeV Advanced Photon Source Conceptual Design Report

    SciTech Connect (OSTI)

    Not Available

    1987-04-01

    During the past decade, synchrotron radiation emitted by circulating electron beams has come into wide use as a powerful, versatile source of x-rays for probing the structure of matter and for studying various physical processes. Several synchrotron radiation facilities with different designs and characteristics are now in regular operation throughout the world, with recent additions in this country being the 0.8-GeV and 2.5-GeV rings of NSLS at Brookhaven National Laboratory. However, none of the operating facilities has been designed to use a low-emittance, high-energy stored beam, together with modern undulator devices, to produce a large number of hard x-ray beams of extremely high brilliance. This document is a proposal to the Department of Energy to construct and operate high-energy synchrotron radiation facility at Argonne National Laboratory. We have now chosen to set the design energy of this facility at 7.0 GeV, with the capability to operate at up to 7.5 GeV.

  2. Near-Infrared Photoluminescence Enhancement in Ge/CdS and Ge/ZnS Core/Shell Nanocrystals: Utilizing IV/II-VI Semiconductor Epitaxy

    SciTech Connect (OSTI)

    Guo, Yijun [Ames Laboratory; Rowland, Clare E [Argonne National Laboratory; Schaller, Richard D [Argonne National Laboratory; Vela, Javier [Ames Laboratory

    2014-08-26

    Ge nanocrystals have a large Bohr radius and a small, size-tunable band gap that may engender direct character via strain or doping. Colloidal Ge nanocrystals are particularly interesting in the development of near-infrared materials for applications in bioimaging, telecommunications and energy conversion. Epitaxial growth of a passivating shell is a common strategy employed in the synthesis of highly luminescent II–VI, III–V and IV–VI semiconductor quantum dots. Here, we use relatively unexplored IV/II–VI epitaxy as a way to enhance the photoluminescence and improve the optical stability of colloidal Ge nanocrystals. Selected on the basis of their relatively small lattice mismatch compared with crystalline Ge, we explore the growth of epitaxial CdS and ZnS shells using the successive ion layer adsorption and reaction method. Powder X-ray diffraction and electron microscopy techniques, including energy dispersive X-ray spectroscopy and selected area electron diffraction, clearly show the controllable growth of as many as 20 epitaxial monolayers of CdS atop Ge cores. In contrast, Ge etching and/or replacement by ZnS result in relatively small Ge/ZnS nanocrystals. The presence of an epitaxial II–VI shell greatly enhances the near-infrared photoluminescence and improves the photoluminescence stability of Ge. Ge/II–VI nanocrystals are reproducibly 1–3 orders of magnitude brighter than the brightest Ge cores. Ge/4.9CdS core/shells show the highest photoluminescence quantum yield and longest radiative recombination lifetime. Thiol ligand exchange easily results in near-infrared active, water-soluble Ge/II–VI nanocrystals. We expect this synthetic IV/II–VI epitaxial approach will lead to further studies into the optoelectronic behavior and practical applications of Si and Ge-based nanomaterials.

  3. The polygallides: Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub2}.

    SciTech Connect (OSTI)

    Peter, S. C.; Malliakas, C. D.; Nakotte, H.; Kothapilli, K.; Rayaprol, S.; Schultz, A. J.; Kanatzidis, M. G. (Materials Science Division); ( XSD); (Northwestern Univ.); (Jawaharlal Nehru Centre for Adv. Sci. Res.); (New Mexico State Univ.); (Los Alamos Nat. Lab.); (UGC-DAE Consortium for Sci. Res.)

    2012-03-01

    Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub 2} were obtained from reactions of Yb and Ge in excess liquid gallium. The crystal structure of Yb{sub 3}Ga{sub 7}Ge{sub 3} was refined using X-ray and neutron diffraction data on selected single crystals. Yb{sub 3}Ga{sub 7}Ge{sub 3} crystallizes in the monoclinic space group C2/c with lattice constants a = 12.2261(20) {angstrom}, b = 10.7447(20) {angstrom}, c = 8.4754(17) {angstrom} and {beta} = 110.288(30){sup o} (neutron diffraction data). The crystal structure of Yb{sub 3}Ga{sub 7}Ge{sub 3} is an intergrowth of planar layers of YbGa{sub x}Ge{sub y} and puckered layers of (Ge)n. YbGa{sub 4}Ge{sub 2} crystallizes in a modified PuGa{sub 6} structure type in the tetragonal polar space group I4cm with lattice constants a = b = 5.9874(6) {angstrom} and c = 15.1178(19) {angstrom}. The structure of YbGa{sub 4}Ge{sub 2} is an intergrowth of puckered Ga layers and puckered Ga{sub x}Ge{sub y} layers with Yb atoms residing within the channels formed by the connection of the two layers. Physical properties, resistivity ({rho}), magnetic susceptibility ({chi}) and specific heat (C) were measured for Yb{sub 3}Ga{sub 7}Ge{sub 3}. No magnetic ordering was observed. It was found that at low temperatures, {rho} varied as T{sup 2} and C{alpha}T, indicating Fermi-liquid regime in Yb{sub 3}Ga{sub 7}Ge{sub 3} at low temperatures.

  4. Large inherent optical gain from the direct gap transition of Ge thin films

    E-Print Network [OSTI]

    Wang, Xiaoxin

    The recent demonstration of Ge-on-Si diode lasers renews the interest in the unique carrier dynamics of Ge involving both direct (?) and indirect (L) valleys. Here, we report a large inherent direct gap optical gain ...

  5. GeV electron beams from cm-scale channel guided laser wakefield accelerator

    E-Print Network [OSTI]

    2008-01-01

    GeV electron beams from cm-scale channel guided laser wake?the generation of GeV-class electron beams using an intenseranges and high-quality electron beams with energy up to 1

  6. GeV electron beams from a centimeter-scale laser-driven plasma accelerator

    E-Print Network [OSTI]

    2008-01-01

    GeV electron beams from cm-scale channel guided laser wake?the generation of GeV-class electron beams using an intenseranges and high-quality electron beams with energy up to 1

  7. Beam On Target! - CEBAF Accelerator Achieves 12 GeV Commissioning...

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

    in an experimental hall, recording the first data of the 12 GeV era. The machine sent electrons around the racetrack three times (known as "3-pass" beam), resulting in 6.11 GeV...

  8. A new physics era at 12 GeV | Jefferson Lab

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

    A new physics era at 12 GeV January 29, 2015 In several articles over the past years, we have written of progress with the CEBAF 12 GeV Upgrade Project. Since the beginning of...

  9. Commercialization potential of compositionally graded Ge - Si??x?Gex? - Si substrates for solar applications

    E-Print Network [OSTI]

    Goh, Johnathan Jian Ming

    2006-01-01

    This project considers the potential of Ge - Si??x?Gex? - Si substrates for solar applications. The use of compositionally graded substrates to achieve heterointegration across different materials platforms such as Si, Ge ...

  10. Discovery of GeV Emission tfrom the Circinus Galaxy with the...

    Office of Scientific and Technical Information (OSTI)

    Discovery of GeV Emission tfrom the Circinus Galaxy with the Fermi-Lat Citation Details In-Document Search Title: Discovery of GeV Emission tfrom the Circinus Galaxy with the...

  11. High Power Millimeter-Wave Signal Generation in Advanced SiGe and CMOS Process

    E-Print Network [OSTI]

    Lin, Hsin-Chang

    2015-01-01

    1.3 Millimeter-Wave Signal Generation 1.4 ThesisPower Millimeter-Wave Signal Generation in Advanced SiGe andPower Millimeter-Wave Signal Generation in Advanced SiGe and

  12. EA-0389: Proposed 7-GeV Advanced Photon Source, Argonne, Illinois

    Broader source: Energy.gov [DOE]

    This EA evaluates the environmental impacts of a proposal for construction and operation of a 6- to 7-GeV synchrotron radiation source known as the 7-GeV Advanced Photon Source at DOE's Argonne...

  13. Epitaxial Ge/Il-V Heterostructures : MOCVD growth, characterization, and applications

    E-Print Network [OSTI]

    Bai, Yu, Ph.D. Massachusetts Institute of Technology

    2011-01-01

    Epitaxial Ge thin films are being investigated for many important roles in next generation microelectronics. Metal-oxide-semiconductor field effect transistors (MOSFETs) utilizing Ge channels have demonstrated dramatic ...

  14. Optical Observations of Gamma-Ray Bursts: Connections to GeV...

    Office of Scientific and Technical Information (OSTI)

    Optical Observations of Gamma-Ray Bursts: Connections to GeVTeV Jets Citation Details In-Document Search Title: Optical Observations of Gamma-Ray Bursts: Connections to GeVTeV...

  15. GE to Invest in Penn State Center to Study Natural Gas Supply...

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

    window) GE to Invest in Penn State Center to Study Natural Gas Supply Chains University Park, Pa. - GE announced it will invest up to 10 million in Penn State to establish a new...

  16. LIFETIME AND RADIATIVE EFFICIENCY VS DENSITY IN THE STRAIN-CONFINED ELECTRON-HOLE LIQUID IN Ge

    E-Print Network [OSTI]

    Kelso, Susan M.

    2011-01-01

    electron-hole liquid (SCEHL) in Ge. Sample CR50 was T = 1.9CONFINED ELECTRON-HOLE LIQUID IN Ge Susan M. Kelso and JohnCONFINED ELECTRON-HOLE LIQUID IN Ge Susan M. Kelso and John

  17. Ris-M-2737 ' / > ^ ' ' . / , / -THE PHASES OF Pb/Ge(lll)

    E-Print Network [OSTI]

    #12;Risø-M-2737 ' / > ^ ' ' . / , / - THE PHASES OF Pb/Ge(lll): A SURFACE X-RAY DIFFRACTION STUDY of a chemisorbed overlayer of Pb on the Ge(lll) surface. Three phases of Pb/Ge(lll) exist in the monolayer regime: the a- and B-phases with a V3xV3R30° unit cell, and a high-temperature IX1 phase. In the 1X1 phase of Pb/Ge

  18. Distinct local electronic structure and magnetism for Mn in amorphous Si and Ge

    E-Print Network [OSTI]

    Zeng, Li

    2010-01-01

    ferromagnetic Mn 5 Ge 3 for spintronic applications. Phys.dopants of interest for spintronic applications, where both

  19. 2D-GE IMAGE SEGMENTATION BASED ON LEVEL-SETS E.A. Mylona a

    E-Print Network [OSTI]

    Athens, University of

    2D-GE IMAGE SEGMENTATION BASED ON LEVEL-SETS E.A. Mylona a , M.A. Savelonas a , D. Maroulis a , M of protein spots in 2D-GE images. The proposed scheme incorporates a protein spot detection stage based both software packages in terms of segmentation performance. Index Terms--2D-GE Images, Protein Spot

  20. Distinct local electronic structure and magnetism for Mn in amorphous Si and Ge

    E-Print Network [OSTI]

    Zeng, Li

    2010-01-01

    Mn-Si (red squares) and Mn-Ge distances (blue circles) d asof the number of Si or Ge nearest neighbours N c ; (c) localthree Mn atoms with different N c in a-Mn 0.094 Ge 0.906 .

  1. Black Ge Based on Crystalline/Amorphous Core/Shell Nanoneedle Arrays

    E-Print Network [OSTI]

    Javey, Ali

    Black Ge Based on Crystalline/Amorphous Core/Shell Nanoneedle Arrays Yu-Lun Chueh,,§,|,# Zhiyong, ROC ABSTRACT Direct growth of black Ge on low-temperature substrates, including plastics and rubber is reported. The material is based on highly dense, crystalline/amorphous core/shell Ge nanoneedle arrays

  2. Defects in Ge and Si caused by 1 MeV Si+ implantation*

    E-Print Network [OSTI]

    Florida, University of

    Defects in Ge and Si caused by 1 MeV Si+ implantation* D. P. Hickeya Department of Materials defect formation and evolution in the 001 Ge and Si wafers implanted with 1 MeV Si+ and 40 keV Si dissolve at the projected range for nonamorphizing implants into Si. However, in Ge, no 311 defect

  3. Formation of Ge nanoclusters on Si(1 1 1)-7 7 surface at high temperature

    E-Print Network [OSTI]

    Gao, Hongjun

    Formation of Ge nanoclusters on Si(1 1 1)-7 · 7 surface at high temperature H.M. Guo, Y.L. Wang, H for publication 17 May 2004 Available online 5 June 2004 Abstract We report on Ge nanocluster formation on Si(1 1 of the Ge clusters are more uniform than those obtained at room temperature due to an increase

  4. Transistor-Based Ge/SOI Photodetector for Integrated Silicon Photonics

    E-Print Network [OSTI]

    Luo, Xi

    2011-01-01

    11. Y. -H. Kuo, Y. -K. Lee, Y. Ge, S. Ren, J. E. Roth, T. I.Colace and G. Assanto, “Poly-Ge Near-infrared PhotodetectorsMasini and G. Assanto, “Ge on Si p-i-n photodiodes operating

  5. Alloyed junction Ge Esaki diodes on Si substrates realised by aspect ratio trapping

    E-Print Network [OSTI]

    Rommel, Sean

    Alloyed junction Ge Esaki diodes on Si substrates realised by aspect ratio trapping technique D. Pawlik, S. Sieg, S.K. Kurinec, S.L. Rommel, Z. Cheng, J.-S. Park, J. Hydrick and A. Lochtefeld A Ge Esaki diode is demonstrated on Si atop a coalesced epitaxial layer of Ge grown through narrow openings in SiO2

  6. Materials synthesis and investigation of itinerant ferromagnetism in the UCo?-xFex Ge system

    E-Print Network [OSTI]

    Huang, Kevin

    2009-01-01

    B. UCo 1?x Fe x Ge . . . . . . . . . . . . . 1. Polycrystalvs temperature data of UCo 1?x Fe x Ge from x = 0.0 to x =vs temperature data of UCo 1?x Fe x Ge from x = 0.20 to x =

  7. Ge incorporation inside 4H-SiC during Homoepitaxial growth by chemical vapor

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Ge incorporation inside 4H-SiC during Homoepitaxial growth by chemical vapor deposition. Kassem Ilmenau (Germany) Abstract. In this work, we report on the addition of GeH4 gas during homoepitaxial growth of 4H-SiC by chemical vapour deposition. Ge introduction does not affect dramatically the surface

  8. Room-temperature 1.3 pm electroluminescence from strained Si, -,Ge,/Si quantum wells

    E-Print Network [OSTI]

    Room-temperature 1.3 pm electroluminescence from strained Si, -,Ge,/Si quantum wells Q. Mi, X. Xiao report the first room-temperature 1.3 ,um electroluminescence from strained Sir-,Ge,/Si quantum wells to that from the Sit-,GeX wells. A minimum band offset is required to have effective room

  9. GE & AE Extension Request Form, Version 8, Feb 2013, JC Program Extension

    E-Print Network [OSTI]

    Escher, Christine

    GE & AE Extension Request Form, Version 8, Feb 2013, JC Program Extension General English English (GE) Academic English (AE) 2. Which term will this extension begin? Fall Winter Spring Summer 3 of General English do you wish to request? 1 2 3 4 5 6 (GE sessions are 5 weeks) How many General English

  10. Infrared and photoluminescence spectroscopy of p-doped self-assembled Ge dots on Si

    E-Print Network [OSTI]

    Rokhinson, Leonid

    Infrared and photoluminescence spectroscopy of p-doped self-assembled Ge dots on Si L. P and photoluminescence PL spectroscopy of self-assembled Ge dots grown on Si 100 by molecular beam epitaxy. PL spectra show a transition from two- to three-dimensional growth as the Ge thickness exceeds 7 Å. The sum

  11. Why is GeV physics relevant in the age of the LHC?

    SciTech Connect (OSTI)

    Pennington, Michael R. [JLAB

    2014-02-01

    The contribution that Jefferson Lab has made, with its 6 GeV electron beam, and will make, with its 12 GeV upgrade, to our understanding of the way the fundamental interactions work, particularly strong coupling QCD, is outlined. The physics at the GeV scale is essential even in TeV collisions.

  12. Atomic and electronic structure of styrene on Ge(100) Do Hwan Kim a

    E-Print Network [OSTI]

    Kim, Sehun

    Atomic and electronic structure of styrene on Ge(100) Do Hwan Kim a , Yun Jeong Hwang b , Junga: Styrene Ge(100) Adsorption DFT calculations STM Coverage-dependent adsorption structures of styrene favorable configuration at room temperature is that the two styrene molecules are bound to two Ge dimers

  13. Thickness effect on the structural and electrical properties of poly-SiGe films

    SciTech Connect (OSTI)

    Asafa, T.B., E-mail: asafa@kfupm.edu.sa [KACST-Intel Consortium Center of Excellence in Nano-manufacturing Applications, Riyadh (Saudi Arabia); imec, Kapeldreef 75, 3001 Leuven (Belgium); King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Witvrouw, A. [imec, Kapeldreef 75, 3001 Leuven (Belgium); Schneider, D. [Fraunhofer-Institute for Material and Beam Technology, Winterbergstrasse 28, Dresden (Germany); Moussa, A. [imec, Kapeldreef 75, 3001 Leuven (Belgium); Tabet, N.; Said, S.A.M. [King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia)

    2014-01-01

    Graphical abstract: - Highlights: • Stress and Young's modulus of poly-SiGe film are linked to the grain columnar structure. • The above properties remain unchanged for poly-SiGe films thicker than 40 nm. • The point of transition is close to the electron mean free path for SiGe. • Both the resistivity and Hall mobility follow a similar trend. - Abstract: As lateral dimensions of electromechanical devices are scaled down to length scales comparable to electron mean free paths, the influence of thickness effect on their properties becomes sine qua non. This paper presents a detailed study of thickness effect on the Young's modulus, residual stress, resistivity and Hall mobility of ultrathin poly-Si{sub 11}Ge{sub 89} films deposited by low pressure chemical vapour deposition. The Young's moduli for the films thicker than ?40 nm are close to the bulk value (135 GPa) while those of the thinner films are much lower. The reduction in resistivity and subsequent improved Hall mobility as thickness increases are discussed in light of surface morphology which is evident from atomic microscopy images. The near constant values of Young's modulus, resistivity and Hall mobility for the films thicker than ?40 nm are attributed to the columnar grain structure as confirmed by the transmission electron microscopy images.

  14. Measurement of the neutron-capture cross section of 76Ge and 74Ge below 15 MeV and its relevance to 0??? decay searches of 76Ge

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

    Bhike, Megha; Fallin, B.; Tornow, W.

    2015-02-01

    The neutron radiative-capture cross section of 76Ge was measured between 0.4 and 14.8 MeV using the activation technique. Germanium samples with the isotopic abundance of View the MathML source?86%Ge76 and View the MathML source?14%Ge74 used in the 0???0??? searches by the GERDA and Majorana Collaborations were irradiated with monoenergetic neutrons produced at eleven energies via the View the MathML sourceH3(p,n)He3, View the MathML sourceH2(d,n)He3 and View the MathML sourceH3(d,n)He4 reactions. Previously, data existed only at thermal energies and at 14 MeV. As a by-product, capture cross-section data were also obtained for 74Ge at neutron energies below 8 MeV. Indium andmore »gold foils were irradiated simultaneously for neutron fluence determination. High-resolution ?-ray spectroscopy was used to determine the ?-ray activity of the daughter nuclei of interest. For the 76Ge total capture cross section the present data are in good agreement with the TENDL-2013 model calculations and the ENDF/B-VII.1 evaluations, while for the View the MathML sourceGe74(n,?)Ge75 reaction, the present data are about a factor of two larger than predicted. It was found that the View the MathML sourceGe74(n,?)Ge75 yield in the High-Purity Germanium (HPGe) detectors used by the GERDA and Majorana Collaborations is only about a factor of two smaller than the View the MathML sourceGe76(n,?)Ge77 yield due to the larger cross section of the former reaction.« less

  15. Medical Imaging Technology | GE Global Research

    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 Administration wouldMass map shines light on dark matter By SarahMODELING Release date: Todd A.FebruaryMaking

  16. GRB 131231A: IMPLICATIONS OF THE GeV EMISSION

    SciTech Connect (OSTI)

    Liu, Bin; Chen, Wei; Liang, Yun-Feng; Zhou, Bei; He, Hao-Ning; Jin, Zhi-Ping; Fan, Yi-Zhong; Wei, Da-Ming [Key laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China); Tam, Pak-Hin Thomas [Institute of Astronomy and Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Shao, Lang, E-mail: liangyf@pmo.ac.cn, E-mail: beizhou@pmo.ac.cn, E-mail: yzfan@pmo.ac.cn, E-mail: dmwei@pmo.ac.cn, E-mail: phtam@phys.nthu.edu.tw [Department of Physics, Hebei Normal University, Shijiazhuang 050024 (China)

    2014-05-20

    GRB 131231A was detected by the Large Area Telescope on board the Fermi Space Gamma-ray Telescope. The high-energy gamma-ray (>100 MeV) afterglow emission spectrum is F {sub ?}??{sup –0.54} {sup ±} {sup 0.15} in the first ?1300 s after the trigger and the most energetic photon has an energy of ?62 GeV, arriving at t ? 520 s. With reasonable parameters of the gamma-ray burst (GRB) outflow as well as the density of the circum-burst medium, the synchrotron radiation of electrons or protons accelerated at an external forward shock have difficulty accounting for the data. Rather, the synchrotron self-Compton radiation of the forward shock-accelerated electrons can account for both the spectrum and temporal behavior of the GeV afterglow emission. We also show that the prospect for detecting GRB 131231A-like GRBs with the Cherenkov Telescope Array is promising.

  17. The 12 GeV Energy Upgrade at Jefferson Laboratory

    SciTech Connect (OSTI)

    Pilat, Fulvia C.

    2012-09-01

    Two new cryomodules and an extensive upgrade of the bending magnets at Jefferson Lab has been recently completed in preparation for the full energy upgrade in about one year. Jefferson Laboratory has undertaken a major upgrade of its flagship facility, the CW re-circulating CEBAF linac, with the goal of doubling the linac energy to 12 GeV. I will discuss here the main scope and timeline of the upgrade and report on recent accomplishments and the present status. I will then discuss in more detail the core of the upgrade, the new additional C100 cryomodules, their production, tests and recent successful performance. I will then conclude by looking at the future plans of Jefferson Laboratory, from the commissioning and operations of the 12 GeV CEBAF to the design of the MEIC electron ion collider.

  18. Evaporation-based Ge/.sup.68 Ga Separation

    DOE Patents [OSTI]

    Mirzadeh, Saed (Albuquerque, NM); Whipple, Richard E. (Los Alamos, NM); Grant, Patrick M. (Los Alamos, NM); O'Brien, Jr., Harold A. (Los Alamos, NM)

    1981-01-01

    Micro concentrations of .sup.68 Ga in secular equilibrium with .sup.68 Ge in strong aqueous HCl solution may readily be separated in ionic form from the .sup.68 Ge for biomedical use by evaporating the solution to dryness and then leaching the .sup.68 Ga from the container walls with dilute aqueous solutions of HCl or NaCl. The chloro-germanide produced during the evaporation may be quantitatively recovered to be used again as a source of .sup.68 Ga. If the solution is distilled to remove any oxidizing agents which may be present as impurities, the separation factor may easily exceed 10.sup.5. The separation is easily completed and the .sup.68 Ga made available in ionic form in 30 minutes or less.

  19. Direct synthesis of highly textured Ge on flexible polyimide films by metal-induced crystallization

    SciTech Connect (OSTI)

    Oya, N.; Toko, K., E-mail: toko@bk.tsukuba.ac.jp; Suemasu, T. [Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573 (Japan); Saitoh, N.; Yoshizawa, N. [Electron Microscope Facility, TIA, AIST, 16-1 Onogawa, Tsukuba 305-8569 (Japan)

    2014-06-30

    The highly (111)-textured Ge thin film (50-nm thickness) is demonstrated on a flexible polyimide film via the low-temperature crystallization (325?°C) of amorphous Ge using Al as a catalyst. Covering the polyimide with insulators significantly improved the crystal quality of the resulting Ge layer. In particular, SiN covering led to 97% (111)-oriented Ge with grains 200??m in size, two orders larger than the grain size of polycrystalline Ge directly formed on the polyimide film. This achievement will give a way to realize advanced electronic and optical devices simultaneously allowing for high performance, inexpensiveness, and flexibility.

  20. Gamma-Ray Bursts Above 1 GeV

    E-Print Network [OSTI]

    Matthew G. Baring

    1997-11-21

    One of the principal results obtained by the Compton Gamma Ray Observatory relating to the study of gamma-ray bursts was the detection by the EGRET instrument of energetic ($>$100 MeV) photons from a handful of bright bursts. The most extreme of these was the single 18 GeV photon from the GRB940217 source. Given EGRET's sensitivity and limited field of view, the detection rate implies that such high energy emission may be ubiquitous in bursts. Hence expectations that bursts emit out to at least TeV energies are quite realistic, and the associated target-of-opportunity activity of the TeV gamma-ray community is well-founded. This review summarizes the observations and a handful of theoretical models for generating GeV--TeV emission in bursts sources, outlining possible ways that future positive detections could discriminate between different scenarios. The power of observations in the GeV--TeV range to distinguish between spectral structure intrinsic to bursts and that due to the intervening medium between source and observer is also discussed.

  1. Quantum confinement in Si and Ge nanostructures: Theory and experiment

    SciTech Connect (OSTI)

    Barbagiovanni, Eric G.; Lockwood, David J.; Simpson, Peter J.; Goncharova, Lyudmila V.

    2014-03-15

    The role of quantum confinement (QC) in Si and Ge nanostructures (NSs) including quantum dots, quantum wires, and quantum wells is assessed under a wide variety of fabrication methods in terms of both their structural and optical properties. Structural properties include interface states, defect states in a matrix material, and stress, all of which alter the electronic states and hence the measured optical properties. We demonstrate how variations in the fabrication method lead to differences in the NS properties, where the most relevant parameters for each type of fabrication method are highlighted. Si embedded in, or layered between, SiO{sub 2}, and the role of the sub-oxide interface states embodies much of the discussion. Other matrix materials include Si{sub 3}N{sub 4} and Al{sub 2}O{sub 3}. Si NSs exhibit a complicated optical spectrum, because the coupling between the interface states and the confined carriers manifests with varying magnitude depending on the dimension of confinement. Ge NSs do not produce well-defined luminescence due to confined carriers, because of the strong influence from oxygen vacancy defect states. Variations in Si and Ge NS properties are considered in terms of different theoretical models of QC (effective mass approximation, tight binding method, and pseudopotential method). For each theoretical model, we discuss the treatment of the relevant experimental parameters.

  2. Exclusive processes at JLab at 6 GeV

    SciTech Connect (OSTI)

    Kim, Andrey

    2015-01-01

    Deeply virtual exclusive reactions provide a unique opportunity to probe the complex internal structure of the nucleon. They allow to access information about the correlations between parton transverse spatial and longitudinal momentum distributions from experimental observables. Dedicated experiments to study Deeply Virtual Compton Scattering (DVCS) and Deeply Virtual Meson Production (DVMP) have been carried out at Jefferson Lab using continuous electron beam with energies up to 6 GeV. Unpolarized cross sections, beam, target and double spin asymmetries have been measured for DVCS as well as for ?0 exclusive electroproduction. The data from Hall B provide a wide kinematic coverage with Q2=1-4.5 GeV2, xB=0.1-0.5, and ?t up to 2 GeV2. Hall A data have limited kinematic range partially overlapping with Hall B kinematics but provide a high accuracy measurements. Scaling tests of the DVCS cross sections provide solid evidence of twist-2 dominance, which makes chiral-even GPDs accessible even at modest Q2. We will discuss the interpretation of these data in terms of Generalized Parton Distributions (GPDs) model. Successful description of the recent CLAS ?0 exclusive production data within the framework of the GPD-based model provides a unique opportunity to access the chiral-odd GPDs.

  3. On the origin of GeV emission in gamma-ray bursts

    SciTech Connect (OSTI)

    Beloborodov, Andrei M.; Hascoët, Romain; Vurm, Indrek, E-mail: amb@phys.columbia.edu [Physics Department and Columbia Astrophysics Laboratory, Columbia University, 538 West 120th Street, New York, NY 10027 (United States)

    2014-06-10

    The most common progenitors of gamma-ray bursts (GRBs) are massive stars with strong stellar winds. We show that the GRB blast wave in the wind should emit a bright GeV flash. It is produced by inverse-Compton cooling of the thermal plasma behind the forward shock. The main part of the flash is shaped by scattering of the prompt MeV radiation (emitted at smaller radii) which streams through the external blast wave. The inverse-Compton flash is bright due to the huge e {sup ±} enrichment of the external medium by the prompt radiation ahead of the blast wave. At late times, the blast wave switches to normal synchrotron-self-Compton cooling. The mechanism is demonstrated by a detailed transfer simulation. The observed prompt MeV radiation is taken as an input of the simulation; we use GRB 080916C as an example. The result reproduces the GeV flash observed by the Fermi telescope. It explains the delayed onset, the steep rise, the peak flux, the time of the peak, the long smooth decline, and the spectral slope of GeV emission. The wind density required to reproduce all these features is typical of Wolf-Rayet stars. Our simulation predicts strong TeV emission 1 minute after the burst trigger; then a cutoff in the observed high-energy spectrum is expected from absorption by extragalactic background light. In addition, a bright optical counterpart of the GeV flash is predicted for plausible values of the magnetic field; such a double (optical+GeV) flash has been observed in GRB 130427A.

  4. Strained Sistrained Ge dual-channel heterostructures on relaxed Si0.5Ge0.5 for symmetric mobility p-type and n-type metal-oxide-semiconductor

    E-Print Network [OSTI]

    Strained SiÕstrained Ge dual-channel heterostructures on relaxed Si0.5Ge0.5 for symmetric mobility By growing heterostructures that combine a surface strained Si layer with a buried strained Ge layer on Si0.5Ge0.5 , we have fabricated metal-oxide-semiconductor field-effect transistors with mobility

  5. The polygallides: Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub 2}

    SciTech Connect (OSTI)

    Peter, Sebastian C. [Department of Chemistry, Northwestern University, 2145N. Sheridan Road, Evanston, IL 60208 (United States); New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064 (India); Malliakas, Christos D. [Department of Chemistry, Northwestern University, 2145N. Sheridan Road, Evanston, IL 60208 (United States); Nakotte, Heinze; Kothapilli, Karunakar [Physics Department, New Mexico State University, Las Cruces, NM 88003 (United States); Los Alamos Neutron Science Center, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Rayaprol, Sudhindra [UGC-DAE Consortium for Scientific Research, Mumbai Centre, BARC, R-5 Shed, Trombay, Mumbai 400085 (India); Schultz, Arthur J. [X-Ray Science Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Kanatzidis, Mercouri G., E-mail: m-kanatzidis@northwestern.edu [Department of Chemistry, Northwestern University, 2145N. Sheridan Road, Evanston, IL 60208 (United States); Materials Science Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

    2012-03-15

    Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub 2} were obtained from reactions of Yb and Ge in excess liquid gallium. The crystal structure of Yb{sub 3}Ga{sub 7}Ge{sub 3} was refined using X-ray and neutron diffraction data on selected single crystals. Yb{sub 3}Ga{sub 7}Ge{sub 3} crystallizes in the monoclinic space group C2/c with lattice constants a=12.2261(20) Angstrom-Sign , b=10.7447(20) Angstrom-Sign , c=8.4754(17) Angstrom-Sign and {beta}=110.288(30) Degree-Sign (neutron diffraction data). The crystal structure of Yb{sub 3}Ga{sub 7}Ge{sub 3} is an intergrowth of planar layers of YbGa{sub x}Ge{sub y} and puckered layers of (Ge){sub n}. YbGa{sub 4}Ge{sub 2} crystallizes in a modified PuGa{sub 6} structure type in the tetragonal polar space group I4cm with lattice constants a=b=5.9874(6) Angstrom-Sign and c=15.1178(19) Angstrom-Sign . The structure of YbGa{sub 4}Ge{sub 2} is an intergrowth of puckered Ga layers and puckered Ga{sub x}Ge{sub y} layers with Yb atoms residing within the channels formed by the connection of the two layers. Physical properties, resistivity ({rho}), magnetic susceptibility ({chi}) and specific heat (C) were measured for Yb{sub 3}Ga{sub 7}Ge{sub 3}. No magnetic ordering was observed. It was found that at low temperatures, {rho} varied as T{sup 2} and C{proportional_to}T, indicating Fermi-liquid regime in Yb{sub 3}Ga{sub 7}Ge{sub 3} at low temperatures. - Graphical abstract: The compounds Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub 2} are obtained from reactions of Yb and Ge in excess liquid gallium. Highlights: Black-Right-Pointing-Pointer Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub 2} are two new polygallides. Black-Right-Pointing-Pointer The crystal structure of Yb{sub 3}Ga{sub 7}Ge{sub 3} was established using neutron diffraction data. Black-Right-Pointing-Pointer YbGa{sub 4}Ge{sub 2} is one of the rare polar intermetallic compounds. Black-Right-Pointing-Pointer The physical properties of Yb{sub 3}Ga{sub 7}Ge{sub 3} point to a Fermi-liquid regime at low temperature.

  6. Smart Street Lights | GE Global Research

    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 RoomPreservation ofAlbuquerque|Sensitive Species3performed StevenSmall

  7. Effect of graphene on photoluminescence properties of graphene/GeSi quantum dot hybrid structures

    SciTech Connect (OSTI)

    Chen, Y. L.; Ma, Y. J.; Wang, W. Q.; Ding, K.; Wu, Q.; Fan, Y. L.; Yang, X. J.; Zhong, Z. Y.; Jiang, Z. M., E-mail: zmjiang@fudan.edu.cn [State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education) and Department of Physics, Fudan University, Shanghai 200433 (China); Chen, D. D.; Xu, F. [SHU-SolarE R and D Lab, Department of Physics, College of Science, Shanghai University, Shanghai 200444 (China)

    2014-07-14

    Graphene has been discovered to have two effects on the photoluminescence (PL) properties of graphene/GeSi quantum dot (QD) hybrid structures, which were formed by covering monolayer graphene sheet on the multilayer ordered GeSi QDs sample surfaces. At the excitation of 488?nm laser line, the hybrid structure had a reduced PL intensity, while at the excitation of 325?nm, it had an enhanced PL intensity. The attenuation in PL intensity can be attributed to the transferring of electrons from the conducting band of GeSi QDs to the graphene sheet. The electron transfer mechanism was confirmed by the time resolved PL measurements. For the PL enhancement, a mechanism called surface-plasmon-polariton (SPP) enhanced absorption mechanism is proposed, in which the excitation of SPP in the graphene is suggested. Due to the resonant excitation of SPP by incident light, the absorption of incident light is much enhanced at the surface region, thus leading to more exciton generation and a PL enhancement in the region. The results may be helpful to provide us a way to improve optical properties of low dimensional surface structures.

  8. 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

  9. Large-angle production of charged pions by 3 GeV/c - 12.9 GeV/c protons on beryllium, aluminium and lead targets

    E-Print Network [OSTI]

    HARP Collaboration

    2007-09-21

    Measurements of the double-differential $\\pi^{\\pm}$ production cross-section in the range of momentum $100 \\MeVc \\leq p beryllium, proton--aluminium and proton--lead collisions are presented. The data were taken with the HARP detector in the T9 beam line of the CERN PS. The pions were produced by proton beams in a momentum range from 3 \\GeVc to 12.9 \\GeVc hitting a target with a thickness of 5% of a nuclear interaction length. The tracking and identification of the produced particles was performed using a small-radius cylindrical time projection chamber (TPC) placed inside a solenoidal magnet. Incident particles were identified by an elaborate system of beam detectors. Results are obtained for the double-differential cross-sections at six incident proton beam momenta (3 \\GeVc, 5 \\GeVc, 8 \\GeVc, 8.9 \\GeVc (Be only), 12 \\GeVc and 12.9 \\GeVc (Al only)) and compared to previously available data.

  10. GE & AE Extension Request Form, Version 7, Sept 2012, JC Program Extension General English or Academic English

    E-Print Network [OSTI]

    Escher, Christine

    GE & AE Extension Request Form, Version 7, Sept 2012, JC Program Extension ­ General English) General English (GE) Academic English (AE) Which term will this extension begin? Fall Winter Spring Summer more sessions of GE do you wish to request? 1 2 3 4 5 6 Other ____ (GE sessions are 4 weeks) *Please

  11. Correlation Between Optical Properties And Chemical Composition Of Sputter-deposited Germanium Cxide (GeOx) Films

    SciTech Connect (OSTI)

    Murphy, Neil R.; Grant, J. T.; Sun, L.; Jones, J. G.; Jakubiak, R.; Shutthanandan, V.; Ramana, Chintalapalle V.

    2014-03-18

    Germanium oxide (GeOx) films were grown on (1 0 0) Si substrates by reactive Direct-Current (DC) magnetron sputter-deposition using an elemental Ge target. The effects of oxygen gas fraction, ? = O2/(Ar + O2), on the deposition rate, structure, chemical composition and optical properties of GeOx films have been investigated. The chemistry of the films exhibits an evolution from pure Ge to mixed Ge + GeO + GeO2 and then finally to GeO2 upon increasing ? from 0.00 to 1.00. Grazing incidence X-ray analysis indicates that the GeOx films grown were amorphous. The optical properties probed by spectroscopic ellipsometry indicate that the effect of ? is significant on the optical constants of the GeOx films. The measured index of refraction (n) at a wavelength (?) of 550 nm is 4.67 for films grown without any oxygen, indicating behavior characteristic of semiconducting Ge. The transition from germanium to mixed Ge + GeO + GeO2 composition is associated with a characteristic decrease in n (? = 550 nm) to 2.62 and occurs at ? = 0.25. Finally n drops to 1.60 for ? = 0.50–1.00, where the films become GeO2. A detailed correlation between ?, n, k and stoichiometry in DC sputtered GeOx films is presented and discussed.

  12. GE & AE Extension Request Form, Version 6, May 2012, JC Program Extension General English or Academic English

    E-Print Network [OSTI]

    Escher, Christine

    GE & AE Extension Request Form, Version 6, May 2012, JC Program Extension ­ General English) General English (GE) Academic English (AE) Which term will this extension begin? Fall Winter Spring Summer more sessions of GE do you wish to request? 1 2 3 4 5 6 Other ____ (GE sessions are 4 weeks) *Please

  13. GE & AE Program Change Request Form, Version 12, July 2013, ML Program Change-General English or Academic English

    E-Print Network [OSTI]

    Escher, Christine

    GE & AE Program Change Request Form, Version 12, July 2013, ML Program Change-General English English student, and I would like to switch to General English. How many sessions of GE do you wish to request? 1 2 3 4 (GE sessions are 5 weeks) How many GE hours do you wish to take? 21 hours 27 hours

  14. Hot-Wire Deposition of Hydrogenated Nanocrystalline SiGe Films for Thin-Film Si Based Solar Cells

    E-Print Network [OSTI]

    Deng, Xunming

    Hot-Wire Deposition of Hydrogenated Nanocrystalline SiGe Films for Thin-Film Si Based Solar Cells bandgap absorber in an a-Si/a-SiGe/nc-SiGe(nc- Si) triple-junction solar cell due to its higher optical in an a-Si based multiple- junction solar cell. 1. INTRODUCTION Narrow bandgap amorphous SiGe (a

  15. Lattice study of an electroweak phase transition at m{sub h} ? 126 GeV

    SciTech Connect (OSTI)

    Laine, M.; Nardini, G.; Rummukainen, K. E-mail: germano@physik.uni-bielefeld.de

    2013-01-01

    We carry out lattice simulations of a cosmological electroweak phase transition for a Higgs mass m{sub h} ? 126 GeV. The analysis is based on a dimensionally reduced effective theory for an MSSM-like scenario including a relatively light coloured SU(2)-singlet scalar, referred to as a right-handed stop. The non-perturbative transition is stronger than in 2-loop perturbation theory, and may offer a window for electroweak baryogenesis. The main remaining uncertainties concern the physical value of the right-handed stop mass which according to our analysis could be as high as m{sub t-tilde{sub R}} ? 155 GeV; a more precise effective theory derivation and vacuum renormalization than available at present are needed for confirming this value.

  16. Dirac gauginos, R symmetry and the 125 GeV Higgs

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

    Bertuzzo, Enrico; Frugiuele, Claudia; Grégoire, Thomas; Pontón, Eduardo

    2015-04-01

    We study a supersymmetric scenario with a quasi exact R-symmetry in light of the discovery of a Higgs resonance with a mass of 125 GeV. In such a framework, the additional adjoint superfields, needed to give Dirac masses to the gauginos, contribute both to the Higgs mass and to electroweak precision observables. We analyze the interplay between the two aspects, finding regions in parameter space in which the contributions to the precision observables are under control and a 125 GeV Higgs boson can be accommodated. We estimate the fine-tuning of the model finding regions of the parameter space still unexploredmore »by the LHC with a fine-tuning considerably improved with respect to the minimal supersymmetric scenario. In particular, sizable non-holomorphic (non-supersoft) adjoints masses are required to reduce the fine-tuning.« less

  17. Dirac gauginos, R symmetry and the 125 GeV Higgs

    SciTech Connect (OSTI)

    Bertuzzo, Enrico; Frugiuele, Claudia; Grégoire, Thomas; Pontón, Eduardo

    2015-04-01

    We study a supersymmetric scenario with a quasi exact R-symmetry in light of the discovery of a Higgs resonance with a mass of 125 GeV. In such a framework, the additional adjoint superfields, needed to give Dirac masses to the gauginos, contribute both to the Higgs mass and to electroweak precision observables. We analyze the interplay between the two aspects, finding regions in parameter space in which the contributions to the precision observables are under control and a 125 GeV Higgs boson can be accommodated. We estimate the fine-tuning of the model finding regions of the parameter space still unexplored by the LHC with a fine-tuning considerably improved with respect to the minimal supersymmetric scenario. In particular, sizable non-holomorphic (non-supersoft) adjoints masses are required to reduce the fine-tuning.

  18. Characterization of second-phase plates in a Gd5Ge3 intermetallic compound

    SciTech Connect (OSTI)

    Cao, Qing; Chumbley, Leonard S.

    2013-05-16

    Rare-earth compounds based on the stoichiometry R5(SixGe1?x)4 (R = rare-earth elements) exhibit many unusual features, including possessing R5(SixGe1?x)3 thin plates which always precipitate from the matrix despite efforts to suppress their formation. In an effort to better understand the unique relationship between these two intermetallic alloy systems, the bulk microstructure of the compound Gd5Ge3 was examined using scanning (SEM) and transmission electron microscopy (TEM) and optical microscopy. Surprisingly, SEM examination revealed a series of thin plates present in the Gd5Ge3 matrix similar to what is seen in Gd5Ge4. TEM observation revealed that a role reversal had occurred, with the thin plates possessing the orthorhombic structure and composition of Gd5Ge4. The orientation relationship between Gd5Ge4 thin plates and the Gd5Ge3 matrix was determined to be Graphic the same relationship reported for Gd5Ge3 plates precipitating from a Gd5Ge4 matrix. However, by exchanging the respective roles of the phases as regards matrix vs. precipitate, the total number of precipitation variants seen can be increased from two to six. The persistence with which these two intermetallic systems co-exist is truly unique. However, understanding exactly the kinetic and thermodynamic conditions that lead to their unique relationship is hampered by the high formation temperatures at which the observed reaction occurs.

  19. Synthesis, crystal structure and properties of [(dien){sub 2}Mn]Ge{sub 2}S{sub 4} with mixed-valent Ge centers

    SciTech Connect (OSTI)

    Yue, Cheng-Yang; Yuan, Zhuang-Dong; Zhang, Lu-Ge; Wang, Ya-Bai; Liu, Guo-Dong; Gong, Liao-Kuo; Lei, Xiao-Wu

    2013-10-15

    One new manganese thiogermanate, [(dien){sub 2}Mn]Ge{sub 2}S{sub 4} (dien=diethylenetriamine), was prepared under mild solvothermal conditions and structurally and spectroscopically characterized. The title compound crystallizes in the orthorhombic system, chiral space group P2{sub 1}2{sub 1}2{sub 1} (no. 19) with a=9.113(4) Å, b=12.475(5) Å, c=17.077(7) Å, V=1941.5(15) Å{sup 3} and Z=4. Its structure features a three-dimensional (3D) network composed of a one-dimensional (1D) [Ge{sub 2}S{sub 4}]{sup 2?} anionic chain and a [(dien){sub 2}Mn]{sup 2+} complex interconnected via various hydrogen bonds. The most interesting structural feature of the compound is the presence of two different oxidation states of germanium centers in the 1D [Ge{sub 2}S{sub 4}]{sup 2?} chain, which is also supported by the result of X-ray photoelectron spectroscopy measurement. The optical property of the title compound has also been studied by UV–vis spectra. - Graphical abstract: One new thiogermanate, [(dien){sub 2}Mn]Ge{sub 2}S{sub 4}, contains a one-dimensional [Ge{sub 2}S{sub 4}]{sup 2?} anionic chain with two different oxidation states of germanium centers. Display Omitted - Highlights: • One new manganese thiogermanate [(dien){sub 2}Mn]Ge{sub 2}S{sub 4} was prepared. • The compound features 1D [Ge{sub 2}S{sub 4}]{sup 2?} chain composed of [Ge{sup II}S{sub 4}] and [Ge{sup IV}S{sub 4}] tetrahedra. • The first example of inorganic–organic hybrid thiogermanates with mixed valent Ge centers.

  20. Formation of nickel germanide on SiO{sub 2}-capped n-Ge to lower its Schottky barrier height

    SciTech Connect (OSTI)

    Lin, Guangyang; Tang, Mengrao; Li, Cheng, E-mail: lich@xmu.edu.cn; Huang, Shihao; Lu, Weifang; Wang, Chen; Yan, Guangming; Chen, Songyan [Semiconductor Photonics Research Center, Department of Physics, Xiamen University, Xiamen, Fujian 361005 (China)] [Semiconductor Photonics Research Center, Department of Physics, Xiamen University, Xiamen, Fujian 361005 (China)

    2013-12-16

    In this Letter, NiGe/SiO{sub 2}/n-Ge ohmic contacts were demonstrated with Ge, rather than Ni, diffusion through the ion-implanted SiO{sub 2} films to form NiGe. The equivalent Schottky barrier height reduced from 0.58?eV for NiGe/n-Ge to ohmic contact. The anomalous diffusion behavior and accumulation of Ge in the SiO{sub 2} near the NiGe/SiO{sub 2} interface can be explained by vacancy-enhanced Ge diffusion. It is proposed that the presence of vacancies and Ge atoms embedded in the SiO{sub 2} layer play a significant role in the current enhancement by generation of multiple levels in the SiO{sub 2} band gap.

  1. GE & AE Program Change Form, Version 9, May 2012, JC Program Change General English or Academic English

    E-Print Network [OSTI]

    Escher, Christine

    GE & AE Program Change Form, Version 9, May 2012, JC Program Change ­ General English or Academic to GE. How many more sessions of GE do you wish to request? 1 2 3 4 5 6 How many GE hours do you wish to take? 21 hours 27 hours 2) ____ I am a GE student, and I would like to switch to AE. How many more

  2. Reliable reduction of Fermi-level pinning at atomically matched metal/Ge interfaces by sulfur treatment

    SciTech Connect (OSTI)

    Kasahara, K.; Yamada, S.; Miyao, M. [Department of Electronics, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan); Sakurai, T.; Sawano, K.; Nohira, H. [Advanced Research Laboratories, Tokyo City University, 8-15-1 Todoroki, Tokyo 158-0082 (Japan); Hamaya, K., E-mail: hamaya@ee.es.osaka-u.ac.jp [Department of Electronics, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan); Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan)

    2014-04-28

    This study demonstrates that by using a sulfur (S) treatment on the Ge surface, a reduction in Fermi level pinning can reproducibly be achieved at atomically matched metal/Ge(111) interfaces. The Schottky barrier height for p-type Ge can be controlled by changing the metal work function despite the metal/Ge junctions. The results indicate that the combination of atomic-arrangement matching and S treatment can remove extrinsic factors influencing Fermi level pinning at metal/Ge interfaces.

  3. Diamond turning of Si and Ge single crystals

    SciTech Connect (OSTI)

    Blake, P.; Scattergood, R.O.

    1988-12-01

    Single-point diamond turning studies have been completed on Si and Ge crystals. A new process model was developed for diamond turning which is based on a critical depth of cut for plastic flow-to-brittle fracture transitions. This concept, when combined with the actual machining geometry for single-point turning, predicts that {open_quotes}ductile{close_quotes} machining is a combined action of plasticity and fracture. Interrupted cutting experiments also provide a meant to directly measure the critical depth parameter for given machining conditions.

  4. Extended Battery Life in Electric Vehicles | GE Global Research

    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 Room NewsInformation Current HABFES OctoberEvan Racah Evan-5 BeamlineGE, Ford, University of

  5. Miniaturized Turbine Offers Desalination Solution | GE Global Research

    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 of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDid you notHeatMaRIEdioxide capture |GE Puts Desalination "on Ice"

  6. Crystal Lake - GE Energy Wind Farm | 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 ECoopButtePower VenturesInformation9) Wind Farm Jump to: navigation, search NameGE

  7. Northern Colorado Wind Energy Center (GE) | 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 APPENDIXsourceII Jump to:Information 3rd| OpenInformationConsortium NAVC JumpGE) Jump to:

  8. Notrees 1B (GE Energy) Wind Farm | 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 APPENDIXsourceII Jump to:Information 3rd|Northfork Electric Coop, IncUSA(TXR150000) |B (GE

  9. Gambit Satellite Work Declassified After 25 Years | GE Global Research

    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 Room NewsInformation Current HABFESOpportunities Nuclear PhysicsGE GlobalGetting&Tools »Gambit

  10. Effects of rapid thermal annealing on the structural and local atomic properties of ZnO: Ge nanocomposite thin films

    SciTech Connect (OSTI)

    Ceylan, Abdullah Ozcan, Sadan; Rumaiz, Abdul K.; Caliskan, Deniz; Ozbay, Ekmel; Woicik, J. C.

    2015-03-14

    We have investigated the structural and local atomic properties of Ge nanocrystals (Ge-ncs) embedded ZnO (ZnO: Ge) thin films. The films were deposited by sequential sputtering of ZnO and Ge thin film layers on z-cut quartz substrates followed by an ex-situ rapid thermal annealing (RTA) at 600?°C for 30, 60, and 90?s under forming gas atmosphere. Effects of RTA time on the evolution of Ge-ncs were investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM), hard x-ray photoelectron spectroscopy (HAXPES), and extended x-ray absorption fine structure (EXAFS). XRD patterns have clearly shown that fcc diamond phase Ge-ncs of sizes ranging between 18 and 27?nm are formed upon RTA and no Ge-oxide peak has been detected. However, cross-section SEM images have clearly revealed that after RTA process, Ge layers form varying size nanoclusters composed of Ge-ncs regions. EXAFS performed at the Ge K-edge to probe the local atomic structure of the Ge-ncs has revealed that as prepared ZnO:Ge possesses Ge-oxide but subsequent RTA leads to crystalline Ge structure without the oxide layer. In order to study the occupied electronic structure, HAXPES has been utilized. The peak separation between the Zn 2p and Ge 3d shows no significant change due to RTA. This implies little change in the valence band offset due to RTA.

  11. Comparative analysis of hole transport in compressively strained InSb and Ge quantum well heterostructures

    SciTech Connect (OSTI)

    Agrawal, Ashish; Barth, Michael; Madan, Himanshu; Datta, Suman [Department of Electrical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Lee, Yi-Jing; Lin, You-Ru; Wu, Cheng-Hsien; Ko, Chih-Hsin; Wann, Clement H. [Taiwan Semiconductor Manufacturing Company, Hsinchu 30078, Taiwan (China); Loubychev, Dmitri; Liu, Amy; Fastenau, Joel [IQE, Inc., Bethlehem, Pennsylvania 18015 (United States); Lindemuth, Jeff [Lake Shore Cryotronics, Westerville, Ohio 43082 (United States)

    2014-08-04

    Compressively strained InSb (s-InSb) and Ge (s-Ge) quantum well heterostructures are experimentally studied, with emphasis on understanding and comparing hole transport in these two-dimensional confined heterostructures. Magnetotransport measurements and bandstructure calculations indicate 2.5× lower effective mass for s-InSb compared to s-Ge quantum well at 1.9?×?10{sup 12}?cm{sup –2}. Advantage of strain-induced m* reduction is negated by higher phonon scattering, degrading hole transport at room temperature in s-InSb quantum well compared to s-Ge heterostructure. Consequently, effective injection velocity is superior in s-Ge compared to s-InSb. These results suggest s-Ge quantum well heterostructure is more favorable and promising p-channel candidate compared to s-InSb for future technology node.

  12. Observation of optical spin injection into Ge-based structures at room temperature

    SciTech Connect (OSTI)

    Yasutake, Yuhsuke; Hayashi, Shuhei; Fukatsu, Susumu; Yaguchi, Hiroyuki

    2013-06-17

    Non-zero spin polarization induced by optical orientation was clearly observed at room temperature in a Ge/Ge{sub 0.8}Si{sub 0.2} quantum well grown on Ge and a Ge layer grown on Si by molecular beam epitaxy, whereas it was absent in bulk Ge. This occurred because indirect-gap photoluminescence (PL), which can obscure the spin-polarization information carried by the direct-gap PL, was quenched by unintentional growth-related defects in the epitaxial layers. Such interpretation was confirmed by applying time gating that effectively removed the indirect-gap PL characterized by a slower rise time, which allowed us to demonstrate the existence of room-temperature spin polarization in bulk Ge.

  13. Irreversible altering of crystalline phase of phase-change Ge-Sb thin films

    SciTech Connect (OSTI)

    Krusin-Elbaum, L.; Shakhvorostov, D.; Cabral, C. Jr.; Raoux, S.; Jordan-Sweet, J. L.

    2010-03-22

    The stability of the crystalline phase of binary phase-change Ge{sub x}Sb{sub 1-x} films is investigated over a wide range of Ge content. From Raman spectroscopy we find the Ge-Sb crystalline structure irreversibly altered after exposure to a laser beam. We show that with increasing beam intensity/temperature Ge agglomerates and precipitates out in the amount growing with x. A simple empirical relation links Ge precipitation temperature T{sub Ge}{sup p} to the rate of change dT{sub cryst}/dx of crystallization, with the precipitation easiest on the mid-range x plateau, where T{sub cryst} is nearly constant. Our findings point to a preferable 15% < or approx. x < 50% window, that may achieve the desired cycling/archival properties of a phase-change cell.

  14. Study of plutonium disposition using existing GE advanced Boiling Water Reactors

    SciTech Connect (OSTI)

    Not Available

    1994-06-01

    The end of the cold war and the resulting dismantlement of nuclear weapons has resulted in the need for the US to dispose of 50 to 100 metric tons of excess of plutonium in a safe and proliferation resistant manner. A number of studies, including the recently released National Academy of Sciences (NAS) study, have recommended conversion of plutonium into spent nuclear fuel with its high radiation barrier as the best means of providing permanent conversion and long-term diversion resistance to this material. The NAS study ``Management and Disposition of Excess Weapons Plutonium identified Light Water Reactor spent fuel as the most readily achievable and proven form for the disposition of excess weapons plutonium. The study also stressed the need for a US disposition program which would enhance the prospects for a timely reciprocal program agreement with Russia. This summary provides the key findings of a GE study where plutonium is converted into Mixed Oxide (MOX) fuel and a typical 1155 MWe GE Boiling Water Reactor (BWR) is utilized to convert the plutonium to spent fuel. A companion study of the Advanced BWR has recently been submitted. The MOX core design work that was conducted for the ABWR enabled GE to apply comparable fuel design concepts and consequently achieve full MOX core loading which optimize plutonium throughput for existing BWRs.

  15. LArGe - Active background suppression using argon scintillation for the GERDA $0???$-experiment

    E-Print Network [OSTI]

    M. Agostini; M. Barnabé-Heider; D. Budjáš; C. Cattadori; A. Gangapshev; K. Gusev; M. Heisel; M. Junker; A. Klimenko; A. Lubashevskiy; K. Pelczar; S. Schönert; A. Smolnikov; G. Zuzel

    2015-06-11

    LArGe is a GERDA low-background test facility to study novel background suppression methods in a low-background environment, for future application in the GERDA experiment. Similar to GERDA, LArGe operates bare germanium detectors submersed into liquid argon (1 m$^3$, 1.4 tons), which in addition is instrumented with photomultipliers to detect argon scintillation light. The scintillation signals are used in anti-coincidence with the germanium detectors to effectively suppress background events that deposit energy in the liquid argon. The background suppression efficiency was studied in combination with a pulse shape discrimination (PSD) technique using a BEGe detector for various sources, which represent characteristic backgrounds to GERDA. Suppression factors of a few times $10^3$ have been achieved. First background data of LArGe with a coaxial HPGe detector (without PSD) yield a background index of (0.12$-$4.6)$\\cdot 10^{-2}$ cts/(keV$\\cdot$kg$\\cdot$y) (90% C.L.), which is at the level of GERDA Phase I. Furthermore, for the first time we monitor the natural $^{42}$Ar abundance (parallel to GERDA), and have indication for the $2\

  16. Tensile-strain and doping enhanced direct bandgap optical transition of n{sup +} doped Ge/GeSi quantum wells

    SciTech Connect (OSTI)

    Fan, W. J.

    2013-11-14

    Band structures of tensile strained and n{sup +} doped Ge/GeSi quantum wells (QWs) are calculated by multiple-band k·p method. The energy dispersion curves of the ? and L conduction subbands are obtained. The effects of tensile strain and n{sup +} doping in Ge on direct bandgap optical gain and spontaneous radiative recombination rate spectra are investigated including the electron leakage from ? to L conduction subbands. Our results show that the optical gain and spontaneous radiative recombination rate can be significantly increased with the tensile strain, n-type doping concentration, and injection carrier density in the Ge QW. The free carrier absorption is calculated and cannot be ignored because of the heavily doped Ge. The pure TM mode polarized net optical gain up to 1153?cm{sup ?1} can be achieved for the Ge/Ge{sub 0.986}Si{sub 0.014} QW with tensile strain of 1.61% and n-type doping concentration of 30?×?10{sup 18}?cm{sup ?3}.

  17. Results on neutrinoless double beta decay of 76 Ge from Gerda Phase I

    E-Print Network [OSTI]

    Results on neutrinoless double beta decay of 76 Ge from Gerda Phase I M. Agostini,14 M. Allardt,3 E and a lower limit is derived for the half-life of neutrinoless double beta decay of 76 Ge, T0 1/2> 2.1 · 1025 double beta decay of the isotope 76 Ge. Data con- sidered in the present analysis have been collected

  18. Detector development for Jefferson Lab's 12GeV Upgrade

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

    Qiang, Yi

    2015-05-01

    Jefferson Lab will soon finish its highly anticipated 12 GeV Upgrade. With doubled maximum energy, Jefferson Lab’s Continuous Electron Beam Accelerator Facility (CEBAF) will enable a new experimental program with substantial discovery potential, addressing important topics in nuclear, hadronic and electroweak physics. In order to take full advantage of the high energy, high luminosity beam, new detectors are being developed, designed and constructed to fit the needs of different physics topics. The paper will give an overview of various new detector technologies to be used for 12 GeV experiments. It will then focus on the development of two solenoid-based spectrometers,more »the GlueX and SoLID spectrometers. The GlueX experiment in Hall D will study the complex properties of gluons through exotic hybrid meson spectroscopy. The GlueX spectrometer, a hermetic detector package designed for spectroscopy and the associated partial wave analysis, is currently in the final stage of construction. Hall A, on the other hand, is developing the SoLID spectrometer to capture the 3D image of the nucleon from semi-inclusive processes and to study the intrinsic properties of quarks through mirror symmetry breaking. Such a spectrometer will have the capability to handle very high event rates while still maintaining a large acceptance in the forward region.« less

  19. 12 GeV Upgrade Project - Cryomodule Production

    SciTech Connect (OSTI)

    J. Hogan, A. Burrill, G.K. Davis, M.A. Drury, M. Wiseman

    2012-07-01

    The Thomas Jefferson National Accelerator Facility (Jefferson Lab) is producing ten 100+MV SRF cryomodules (C100) as part of the CEBAF 12 GeV Upgrade Project. Once installed, these cryomodules will become part of an integrated accelerator system upgrade that will result in doubling the energy of the CEBAF machine from 6 to 12 GeV. This paper will present a complete overview of the C100 cryomodule production process. The C100 cryomodule was designed to have the major components procured from private industry and assembled together at Jefferson Lab. In addition to measuring the integrated component performance, the performance of the individual components is verified prior to being released for production and assembly into a cryomodule. Following a comprehensive cold acceptance test of all subsystems, the completed C100 cryomodules are installed and commissioned in the CEBAF machine in preparation of accelerator operations. This overview of the cryomodule production process will include all principal performance measurements, acceptance criterion and up to date status of current activities.

  20. Radiation microscope for SEE testing using GeV ions.

    SciTech Connect (OSTI)

    Doyle, Barney Lee; Knapp, James Arthur; Rossi, Paolo; Hattar, Khalid M.; Vizkelethy, Gyorgy; Brice, David Kenneth; Branson, Janelle V.

    2009-09-01

    Radiation Effects Microscopy is an extremely useful technique in failure analysis of electronic parts used in radiation environment. It also provides much needed support for development of radiation hard components used in spacecraft and nuclear weapons. As the IC manufacturing technology progresses, more and more overlayers are used; therefore, the sensitive region of the part is getting farther and farther from the surface. The thickness of these overlayers is so large today that the traditional microbeams, which are used for REM are unable to reach the sensitive regions. As a result, higher ion beam energies have to be used (> GeV), which are available only at cyclotrons. Since it is extremely complicated to focus these GeV ion beams, a new method has to be developed to perform REM at cyclotrons. We developed a new technique, Ion Photon Emission Microscopy, where instead of focusing the ion beam we use secondary photons emitted from a fluorescence layer on top of the devices being tested to determine the position of the ion hit. By recording this position information in coincidence with an SEE signal we will be able to indentify radiation sensitive regions of modern electronic parts, which will increase the efficiency of radiation hard circuits.

  1. Detector development for Jefferson Lab's 12GeV Upgrade

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

    Qiang, Yi [JLAB] (ORCID:0000000170267841)

    2015-05-01

    Jefferson Lab will soon finish its highly anticipated 12 GeV Upgrade. With doubled maximum energy, Jefferson Lab’s Continuous Electron Beam Accelerator Facility (CEBAF) will enable a new experimental program with substantial discovery potential, addressing important topics in nuclear, hadronic and electroweak physics. In order to take full advantage of the high energy, high luminosity beam, new detectors are being developed, designed and constructed to fit the needs of different physics topics. The paper will give an overview of various new detector technologies to be used for 12 GeV experiments. It will then focus on the development of two solenoid-based spectrometers, the GlueX and SoLID spectrometers. The GlueX experiment in Hall D will study the complex properties of gluons through exotic hybrid meson spectroscopy. The GlueX spectrometer, a hermetic detector package designed for spectroscopy and the associated partial wave analysis, is currently in the final stage of construction. Hall A, on the other hand, is developing the SoLID spectrometer to capture the 3D image of the nucleon from semi-inclusive processes and to study the intrinsic properties of quarks through mirror symmetry breaking. Such a spectrometer will have the capability to handle very high event rates while still maintaining a large acceptance in the forward region.

  2. Sr{sub 7}Ge{sub 6}, Ba{sub 7}Ge{sub 6} and Ba{sub 3}Sn{sub 2} -Three new binary compounds containing dumbbells and four-membered chains of tetrel atoms with considerable Ge-Ge {pi}-bonding character

    SciTech Connect (OSTI)

    Siggelkow, Lisa; Hlukhyy, Viktor [Department Chemie, Technische Universitaet Muenchen, Lichtenbergstr. 4, D-85747 Garching (Germany); Faessler, Thomas F., E-mail: thomas.faessler@lrz.tum.de [Department Chemie, Technische Universitaet Muenchen, Lichtenbergstr. 4, D-85747 Garching (Germany)

    2012-07-15

    The germanides Sr{sub 7}Ge{sub 6} and Ba{sub 7}Ge{sub 6} as well as the stannide Ba{sub 3}Sn{sub 2} were prepared by arc melting and annealing in welded tantalum ampoules using induction as well as resistance furnaces. The compounds were investigated by powder and single crystal X-ray diffraction. Sr{sub 7}Ge{sub 6} and Ba{sub 7}Ge{sub 6} crystallize in the Ca{sub 7}Sn{sub 6} structure type (space group Pmna, Z=4: a=7.777(2) A, b=23.595(4) A, c=8.563(2) A, wR{sub 2}=0.081 (all data), 2175 independent reflections, 64 variable parameters for Sr{sub 7}Ge{sub 6} and a=8.0853(6) A, b=24.545(2) A, c=8.9782(8) A, wR{sub 2}=0.085 (all data), 2307 independent reflections, 64 variable parameters for Ba{sub 7}Ge{sub 6}). Ba{sub 3}Sn{sub 2} crystallizes in an own structure type with the space group P4{sub 3}2{sub 1}2, Z=4, a=6.6854(2) A, c=17.842(2) A, wR{sub 2}=0.037 (all data), 1163 independent reflections, 25 variable parameters. In Sr{sub 7}Ge{sub 6} and Ba{sub 7}Ge{sub 6} the Ge atoms are arranged as Ge{sub 2} dumbbells and Ge{sub 4} four-membered atom chains. Their crystal structures cannot be rationalized according to the (8-N) rule. In contrast, Ba{sub 3}Sn{sub 2} presents Sn{sub 2} dumbbells as a main structural motif and thereby can be described as an electron precise Zintl phase. The chemical bonding situation in these structures is discussed on the basis of partial and total Density Of States (DOS) curves, band structures including fatbands, topological analysis of the Electron Localization Function (ELF) as well as Bader analysis of the bond critical points using the programs TB-LMTO-ASA and WIEN2K. While Ba{sub 3}Sn{sub 2} reveals semiconducting behaviour, all germanides Ae{sub 7}Ge{sub 6} (Ae=Ca, Sr, and Ba) show metallic properties and a considerable {pi}-bonding character between the Ge atoms of the four-membered chains and the dumbbells. The {pi}-bonding character of the germanides is best reflected by the resonance hybrid structures {l_brace}[Ge-Ge]{sup 6-}/[Ge-{sup ....}Ge-{sup ....}Ge-{sup ....}Ge]{sup 8-}{r_brace}{r_reversible}{l_brace}[Ge=Ge]{sup 4-}/[Ge-Ge-Ge-Ge]{sup 10-}{r_brace}. - Graphical abstract: The structure of Ba{sub 3}Sn{sub 2} contains Sn{sub 2} dumbbells as a main structural motif and thereby can be described as an electron precise Zintl phase. Ge{sub 2} dumbbells and Ge{sub 4} four-membered atom chains are the predominant features in Sr{sub 7}Ge{sub 6} and Ba{sub 7}Ge{sub 6}. Their crystal structures cannot be rationalized according to the (8-N) rule. While Ba{sub 3}Sn{sub 2} reveals semiconducting behaviour, the germanides Ae{sub 7}Ge{sub 6} (Ae=Ca, Sr, and Ba) show metallic properties and a considerable {pi}-bonding character between the Ge atoms of the four-membered chains and the dumbbells. Highlights: Black-Right-Pointing-Pointer The germanides Sr{sub 7}Ge{sub 6} and Ba{sub 7}Ge{sub 6} as well as the stannide Ba{sub 3}Sn{sub 2} have been synthesized. Black-Right-Pointing-Pointer In Sr{sub 7}Ge{sub 6} and Ba{sub 7}Ge{sub 6} the Ge atoms are arranged as dumbbells and four-membered atom chains. Black-Right-Pointing-Pointer Ba{sub 3}Sn{sub 2} presents Sn{sub 2} dumbbells as a main structural motif. Black-Right-Pointing-Pointer The chemical bonding situation within these structures is discussed.

  3. Effect of stacking sequence on crystallization in Al/a-Ge bilayer thin films

    SciTech Connect (OSTI)

    Zhang, Tianwei; Zhang, Weilin; Ma, Fei, E-mail: mafei@mail.xjtu.edu.cn, E-mail: kwxu@mail.xjtu.edu.cn [State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 (China); Huang, Yuhong [College of Physics and Information Technology, Shaanxi Normal University, Xi'an, Shaanxi 710062 (China); Xu, Kewei, E-mail: mafei@mail.xjtu.edu.cn, E-mail: kwxu@mail.xjtu.edu.cn [State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China and Department of Physics and Opt-electronic Engineering, Xi'an University of Arts and Science, Xi'an, Shaanxi 710065 (China)

    2014-05-15

    Two types of bilayer thin films with different deposition sequences, i.e., amorphous Ge under Al (a-Ge/Al) and the inverse (Al/a-Ge), were prepared by magnetron sputtering at room temperature. In-situ and ex-situ thermal annealing were compared to study the effect of the stacking sequence on crystallization of amorphous Ge. Although metal-induced crystallization occurred in both cases at low temperature, layer exchange was observed only in a-Ge/Al. In fact, compressive stress could usually be produced when Ge atoms diffused into Al grain boundaries and crystallized there. In the a-Ge/Al system, the stress could be released through diffusion of Al atoms onto the surface and formation of hillocks. Thus, grain boundary (GB) mediated crystallization was dominant in the whole process and layer exchange occurred. However, in the Al/a-Ge system, it was difficult for stress to be relaxed because the Ge sublayer and substrate restricted the diffusion of Al atoms. GB-mediated crystallization was, therefore, considerably suppressed and interface-mediated crystallization was preferred without layer exchange. This leads to distinct morphologies of dendrites in the two systems.

  4. GE Hydro Asia Co Ltd formerly Kvaerner Power Equipment Co Ltd...

    Open Energy Info (EERE)

    Hydro Asia Co Ltd formerly Kvaerner Power Equipment Co Ltd Kvaerner Hangfa Jump to: navigation, search Name: GE Hydro Asia Co Ltd (formerly Kvaerner Power Equipment Co., Ltd...

  5. Electrical Spin Injection and Detection in Ge Nanowires and Topological Insulators

    E-Print Network [OSTI]

    Tang, Jianshi

    2014-01-01

    K. Future Perspectives for Spintronic Devices. J. Phys. D:Ferromagnetic Mn 5 Ge 3 for Spintronic Applications. Phys.Magnetic Anisotropy in Spintronic Devices. Spin 02,

  6. Photo-oxidation of Ge Nanocrystals: Kinetic Measurements by In Situ Raman Spectroscopy

    E-Print Network [OSTI]

    2008-01-01

    Photo-oxidation of Ge Nanocrystals: Kinetic Measurements byrate enhancement is due to a photo-chemical process. Thenanocrystals can be rapidly photo-oxidized. This oxidation

  7. GE to DOE General Counsel; Re:Request for Comment on Large Capacity...

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

    to amend the clothes washer test procedure to reflect efficiency standards of large-capacity residential clothes washer machines. GE also urges the DOE to adopt recommended...

  8. A New Kind of Industrial Company: Read GE's 2014 Annual Report...

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

    grid sector. Alstom will benefit from GE's strength in technology, service and in growth markets. In July, we began the spinoff of Synchrony Financial, our Retail Finance...

  9. Distinct local electronic structure and magnetism for Mn in amorphous Si and Ge

    E-Print Network [OSTI]

    Zeng, Li

    2010-01-01

    ferromagnetic Mn 5 Ge 3 for spintronic applications. Phys.Wolf, S. A. et al. Spintronics: a spin-based electronicsdopants of interest for spintronic applications, where both

  10. Optical Observations of Gamma-Ray Bursts: Connections to GeV...

    Office of Scientific and Technical Information (OSTI)

    Observations of Gamma-Ray Bursts: Connections to GeVTeV Jets Vestrand, W. Thomas Los Alamos National Laboratory Astronomy & Astrophysics(79) Astronomy and Astrophysics Astronomy...

  11. ({lambda}, p) Spectrum Analysis in p+A Interactions at 10 GeV/c

    SciTech Connect (OSTI)

    Aslanyan, P. Zh.; Emelyanenko, V. N.

    2007-06-13

    Experimental data from the 2m propane bubble chamber have been analyzed for exotic baryon states search. A number of peculiarities were found in the effective mass spectra of: {lambda}{pi}+({sigma}*+(1382),PDG), {lambda}p and {lambda}pp subsystems. A few events detected on the photographs of the propane bubble chamber exposed to a 10 GeV/c proton beam, were interpreted as S=-2 H0 light(

  12. Mid infrared optical properties of Ge/Si quantum dots with different doping level

    SciTech Connect (OSTI)

    Sofronov, A. N.; Firsov, D. A.; Vorobjev, L. E.; Shalygin, V. A.; Panevin, V. Yu.; Vinnichenko, M. Ya.; Tonkikh, A. A.; Danilov, S. N.

    2013-12-04

    Optical characterization of the Ge/Si quantum dots using equilibrium and photo-induced absorption spectroscopy in the mid-infrared spectral range was performed in this work. Equilibrium absorption spectra were measured in structures with various doping levels for different light polarizations. Photo-induced absorption spectra measured in undoped structure under interband optical excitation of non-equilibrium charge carriers demonstrate the same features as doped sample in equilibrium conditions. Hole energy spectrum was determined from the analysis of experimental data.

  13. A Bunch Length Monitor for JLab 12 GeV Upgrade

    SciTech Connect (OSTI)

    Ahmad, Mahmoud Mohamad Ali; Freyberger, Arne P.; Gubeli, Joseph F.; Krafft, Geoffrey A.

    2013-12-01

    A continuous non-invasive bunch length monitor for the 12 GeV upgrade of Jefferson Lab will be used to determine the bunch length of the beam. The measurement will be done at the fourth dipole of the injector chicane at 123 MeV using the coherent synchrotron light emitted from the dipole. The estimated bunch length is 333 fs. A vacuum chamber will be fabricated and a Radiabeam real time interferometer will be used. In this paper, background, the estimated calculations and the construction of the chamber will be discussed.

  14. Conduction band offset at GeO{sub 2}/Ge interface determined by internal photoemission and charge-corrected x-ray photoelectron spectroscopies

    SciTech Connect (OSTI)

    Zhang, W. F.; Nishimula, T.; Nagashio, K.; Kita, K.; Toriumi, A.

    2013-03-11

    We report a consistent conduction band offset (CBO) at a GeO{sub 2}/Ge interface determined by internal photoemission spectroscopy (IPE) and charge-corrected X-ray photoelectron spectroscopy (XPS). IPE results showed that the CBO value was larger than 1.5 eV irrespective of metal electrode and substrate type variance, while an accurate determination of valence band offset (VBO) by XPS requires a careful correction of differential charging phenomena. The VBO value was determined to be 3.60 {+-} 0.2 eV by XPS after charge correction, thus yielding a CBO (1.60 {+-} 0.2 eV) in excellent agreement with the IPE results. Such a large CBO (>1.5 eV) confirmed here is promising in terms of using GeO{sub 2} as a potential passivation layer for future Ge-based scaled CMOS devices.

  15. IEEE TRANSACTIONS ON DEVICE AND MATERIALS RELIABILITY, VOL. 7, NO. 1, MARCH 2007 181 Impact of Strain or Ge Content on the Threshold

    E-Print Network [OSTI]

    Kumar, M. Jagadesh

    of Strain or Ge Content on the Threshold Voltage of Nanoscale Strained-Si/SiGe Bulk MOSFETs M. Jagadesh--The impact of strain on the threshold voltage of nanoscale strained-Si/SiGe MOSFETs is studied by developing a compact analytical model. Our model includes the effects of strain (Ge mole fraction in SiGe substrate

  16. Massive "spin-2" theories in arbitrary $D \\ge 3$ dimensions

    E-Print Network [OSTI]

    D. Dalmazi; A. L. R. dos Santos; E. L. Mendonça

    2014-08-28

    Here we show that in arbitrary dimensions $D\\ge 3$ there are two families of second order Lagrangians describing massive "spin-2" particles via a nonsymmetric rank-2 tensor. They differ from the usual Fierz-Pauli theory in general. At zero mass one of the families is Weyl invariant. Such massless theory has no particle content in $D=3$ and gives rise, via master action, to a dual higher order (in derivatives) description of massive spin-2 particles in $D=3$ where both the second and the fourth order terms are Weyl invariant, contrary to the linearized New Massive Gravity. However, only the fourth order term is invariant under arbitrary antisymmetric shifts. Consequently, the antisymmetric part of the tensor $e_{[\\mu\

  17. Complexes of self-interstitials with oxygen atoms in Ge

    SciTech Connect (OSTI)

    Khirunenko, L. I.; Pomozov, Yu. V.; Sosnin, M. G.; Abrosimov, N. V.; Riemann, H.

    2014-02-21

    Interactions of germanium self-interstitials with interstitial oxygen atoms in Ge subjected to irradiation at ?80 K and subsequently to annealing have been studied. To distinguish the processes involving vacancies and self-interstitials the doping with tin was used. It was shown that absorption lines with maximum at 602, 674, 713 and 803 cm{sup ?1} are self-interstitials-related. Two lines at 602 and 674, which develop upon annealing in the temperature range 180–240 K, belong to IO complexes, while the bands at 713 and 803 cm{sup ?1}, which emerge after annealing at T>220 K, are associated with I{sub 2}O. It is argued that the annealing of IO occurs by two mechanisms: by dissociation and by diffusion.

  18. Pressure Safety of JLAB 12GeV Upgrade Cryomodule

    SciTech Connect (OSTI)

    Cheng, Gary [JLAB; Wiseman, Mark A. [JLAB; Daly, Ed [JLAB

    2009-11-01

    This paper reviews pressure safety considerations, per the US Department of Energy (DOE) 10CFR851 Final Rule [1], which are being implemented during construction of the 100 Megavolt Cryomodule (C100 CM) for Jefferson Lab’s 12 GeV Upgrade Project. The C100 CM contains several essential subsystems that require pressure safety measures: piping in the supply and return end cans, piping in the thermal shield and the helium headers, the helium vessel assembly which includes high RRR niobium cavities, the end cans, and the vacuum vessel. Due to the vessel sizes and pressure ranges, applicable national consensus code rules are applied. When national consensus codes are not applicable, equivalent design and fabrication approaches are identified and implemented. Considerations for design, material qualification, fabrication, inspection and examination are summarized. In addition, JLAB’s methodologies for implementation of the 10 CFR 851 requirements are described.

  19. Blazar Variability and Evolution in the GeV Regime

    E-Print Network [OSTI]

    Tsujimoto, S; Nishijima, K; Kodani, K

    2015-01-01

    One of the most important problem of the blazar astrophysics is to understand the physical origin of the blazar sequence. In this study, we focus on the GeV gamma-ray variability of blazars and evolution perspective we search the relation between the redshift and the variability amplitude of blazars for each blazar subclass. We analyzed the Fermi-LAT data of the TeV blazars and the bright AGNs (flux $\\geq$ 4$\\times10^{-9}$ cm$^{-2}$s$^{-1}$) selected from the 2LAC (the 2nd LAT AGN catalog) data base. As a result, we found a hint of the correlation between the redshift and the variability amplitude in the FSRQs. Furthermore the BL Lacs which have relatively lower peak frequency of the synchrotron radiation and relatively lower redshift, have a tendency to have a smaller variability amplitude.

  20. Signal modeling of high-purity Ge detectors with a small read-out electrode and application to neutrinoless double beta decay search in Ge-76

    E-Print Network [OSTI]

    M. Agostini; C. A. Ur; D. Budjáš; E. Bellotti; R. Brugnera; C. M. Cattadori; A. di Vacri; A. Garfagnini; L. Pandola; S. Schönert

    2011-01-17

    The GERDA experiment searches for the neutrinoless double beta decay of Ge-76 using high-purity germanium detectors enriched in Ge-76. The analysis of the signal time structure provides a powerful tool to identify neutrinoless double beta decay events and to discriminate them from gamma-ray induced backgrounds. Enhanced pulse shape discrimination capabilities of "Broad Energy Germanium" detectors with a small read-out electrode have been recently reported. This paper describes the full simulation of the response of such a detector, including the Monte Carlo modeling of radiation interaction and subsequent signal shape calculation. A pulse shape discrimination method based on the ratio between the maximum current signal amplitude and the event energy applied to the simulated data shows quantitative agreement with the experimental data acquired with calibration sources. The simulation has been used to study the survival probabilities of the decays which occur inside the detector volume and are difficult to assess experimentally. Such internal decay events are produced by the cosmogenic radio-isotopes Ge-68 and Co-60 and the neutrinoless double beta decay of Ge-76. Fixing the experimental acceptance of the double escape peak of the 2.614 MeV photon to 90%, the estimated survival probabilities at Qbb = 2.039 MeV are (86+-3)% for Ge-76 neutrinoless double beta decays, (4.5+-0.3)% for the Ge-68 daughter Ga-68, and (0.9+0.4-0.2)% for Co-60 decays.

  1. The cross-plane thermoelectric properties of p-Ge/Si{sub 0.5}Ge{sub 0.5} superlattices

    SciTech Connect (OSTI)

    Ferre Llin, L.; Samarelli, A.; Weaver, J. M. R.; Dobson, P. S.; Paul, D. J. [School of Engineering, University of Glasgow, Rankine Building, Oakfield Avenue, Glasgow G12 8LT (United Kingdom)] [School of Engineering, University of Glasgow, Rankine Building, Oakfield Avenue, Glasgow G12 8LT (United Kingdom); Cecchi, S.; Chrastina, D.; Isella, G. [L-NESS, Politecnico di Milano, Via Anzani 42, 22100 Como (Italy)] [L-NESS, Politecnico di Milano, Via Anzani 42, 22100 Como (Italy); Etzelstorfer, T.; Stangl, J. [Institute of Semiconductor and Solid State Physics, Johannes Kepler Universität, Linz (Austria)] [Institute of Semiconductor and Solid State Physics, Johannes Kepler Universität, Linz (Austria); Müller Gubler, E. [Electron Microscopy ETH Zurich, ETH Zurich, Wolfgang-Pauli-Str. 16, CH-8093 Zurich (Switzerland)] [Electron Microscopy ETH Zurich, ETH Zurich, Wolfgang-Pauli-Str. 16, CH-8093 Zurich (Switzerland)

    2013-09-30

    The electrical conductivity, Seebeck coefficients, and thermal conductivities of a range of p-type Ge/Si{sub 0.5}Ge{sub 0.5} superlattices designed for thermoelectric generation and grown by low energy plasma enhanced chemical vapor deposition have been measured using a range of microfabricated test structures. For samples with barriers around 0.5 nm in thickness, the measured Seebeck coefficients were comparable to bulk p-SiGe at similar doping levels suggesting the holes see the material as a random bulk alloy rather than a superlattice. The Seebeck coefficients for Ge quantum wells of 2.85 ± 0.85 nm increased up to 533 ± 25 ?V/K as the doping was reduced. The thermal conductivities are between 4.5 to 6.0 Wm{sup ?1}K{sup ?1} which are lower than comparably doped bulk Si{sub 0.3}Ge{sub 0.7} but higher than undoped Si/Ge superlattices. The highest measured figure of merit ZT was 0.080 ± 0.011 obtained for the widest quantum well studied. Analysis suggests that interface roughness is presently limiting the performance and a reduction in the strain between the quantum wells and barriers has the potential to improve the thermoelectric performance.

  2. Infrared absorption of n-type tensile-strained Ge-on-Si

    E-Print Network [OSTI]

    Wang, Xiaoxin

    We analyze the IR absorption of tensile-strained, n-type Ge for Si-compatible laser applications. A strong intervalley scattering from the indirect L valleys to the direct ? valley in n[superscript +] Ge-on-Si is reported ...

  3. Donor-vacancy pairs in irradiated n-Ge: A searching look at the problem

    SciTech Connect (OSTI)

    Emtsev, Vadim; Oganesyan, Gagik [IoffePhysicotechnical Institute, Russian Academy of Sciences, Politekhnicheskaya ulitsa 26, 194021 St. Petersburg (Russian Federation)

    2014-02-21

    The present situation concerning the identification of vacancy-donor pairs in irradiated n-Ge is discussed. The challenging points are the energy states of these defects deduced from DLTS spectra. Hall effect data seem to be at variance with some important conclusions drawn from DLTS measurements. Critical points of the radiation-produced defect modeling in n-Ge are highlighted.

  4. GeV electron beams from a centimeter-scale channel guided laser wakefield acceleratora...

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    GeV electron beams from a centimeter-scale channel guided laser wakefield acceleratora... K on the generation of GeV-class electron beams using an intense femtosecond laser beam and a 3.3 cm long preformed from 10­40 TW were guided over more than 20 Rayleigh ranges and high quality electron beams with energy

  5. |. aJr iri? GE DOCUMENT NO. 81AEP-003 DEVELOPMENT AND DEMONSTRATION

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    I / ~'j |. aJr iri? GE DOCUMENT NO. 81AEP-003 DEVELOPMENT AND DEMONSTRATION OF A STIRLING Government or any agency thereof. I #12;GE DOCUMENT NO. 81AEP-003 DEVELOPMENT AND DEMONSTRATION OF A STIRLING . . . . . . . . . . . . . . . . . 2-1 2.2 Engine/Compressor/Combustor Performance . . . . . . 2-1 5*C~~2.2.1 Performance

  6. Understanding Phase Transformation in Crystalline Ge Anodes for Li-Ion Batteries

    E-Print Network [OSTI]

    Cui, Yi

    studies. 1. INTRODUCTION One of the most important renewable energy storage technologies is lithium to silicon. Despite recent studies on Ge electrode reactions, there is still limited understanding elements, such as silicon (Si) and germanium (Ge), are very attractive candidates for high- capacity

  7. FTIR Emission Spectra, Molecular Constants, and Potential Curve of Ground State GeO

    E-Print Network [OSTI]

    Le Roy, Robert J.

    FTIR Emission Spectra, Molecular Constants, and Potential Curve of Ground State GeO Edward G. Lee-resolution FTIR emission spectroscopy measurements for the five common isoto- pomers of GeO are combined­9), photoelectron spectroscopy (10), electronic absorption (11­13), and emission (14) spectroscopy, and in matrix

  8. Experimental Cryogenic Modeling and Noise of SiGe HBTs Joseph C. Bardin and Sander Weinreb

    E-Print Network [OSTI]

    Weinreb, Sander

    Experimental Cryogenic Modeling and Noise of SiGe HBTs Joseph C. Bardin and Sander Weinreb with discussion of performance enhancements due to cooling of the device. Finally, the modeled noise performanceGe), cryogenic, low noise amplifier (LNA), noise parameters, transistor modeling. I. INTRODUCTION Very low-noise

  9. ORIGINAL PAPER Equation of state of MgGeO3 perovskite to 65 GPa: comparison

    E-Print Network [OSTI]

    Duffy, Thomas S.

    ORIGINAL PAPER Equation of state of MgGeO3 perovskite to 65 GPa: comparison with the post-perovskite- erties of the perovskite phase were compared to MgGeO3 post-perovskite phase near the observed phase the properties of the perovskite and post-perovskite phases in silicates. Keywords Germanate Á Perovskite Á

  10. Optical gain from the direct gap transition of Ge-on-Si at room temperature

    E-Print Network [OSTI]

    Liu, Jifeng

    We report direct band gap optical gain of tensile strained n+ epitaxial Ge-on-Si at room temperature, which confirms that band-engineered Ge-on-Si is a promising gain medium for monolithic optical amplifiers and lasers on Si.

  11. Atomic and electronic structure of acetic acid on Ge(100) Do Hwan Kim a,b

    E-Print Network [OSTI]

    Kim, Sehun

    Atomic and electronic structure of acetic acid on Ge(100) Do Hwan Kim a,b , Eunkyung Hwang to investigate the atomic and electronic structure of acetic acid adsorbed on Ge(100) surface. Due to its acidity, acetic acid dissociates and the resulting electron-rich acetate group reacts with the electron

  12. Modern Trend of High-Speed SiGe Heterojunction Bipolar Transistors (HBTs) (Invited Paper)

    E-Print Network [OSTI]

    Rieh, Jae-Sung

    , etc. There certainly exist extra cost for SiGe HBT technology compared to baseline CMOS technology be noted that the cost for the highly expensive phase-shift mask(s) required for CMOS technology to exhibit-gu, Seoul 136-701, Korea jsrieh@korea.ac.kr Abstract SiGe HBT technology has emerged as a strong contender

  13. Measuring Ambient Densities and Lorentz Factors of Gamma-Ray Bursts from GeV and Optical Observations

    E-Print Network [OSTI]

    Hascoët, Romain; Beloborodov, Andrei M

    2015-01-01

    Fermi satellite discovered that cosmological gamma-ray bursts (GRBs) are accompanied by long GeV flashes. In two GRBs, an optical counterpart of the GeV flash has been detected. Recent work suggests that the GeV+optical flash is emitted by the external blast wave from the explosion in a medium loaded with copious $e^\\pm$ pairs. The full light curve of the flash is predicted by a first-principle radiative transfer simulation and can be tested against observations. Here we examine a sample of 7 bursts with best GeV+optical data and test the model. We find that the observed light curves are in agreement with the theoretical predictions and allow us to measure three parameters for each burst: the Lorentz factor of the explosion, its isotropic kinetic energy, and the external density. With one possible exception of GRB 090510 (which is the only short burst in the sample) the ambient medium is consistent with a wind from a Wolf-Rayet progenitor. The wind density parameter $A=\\rho r^2$ varies in the sample around $1...

  14. Direct Detection of sub-GeV Dark Matter with Semiconductor Targets

    E-Print Network [OSTI]

    Rouven Essig; Marivi Fernandez-Serra; Jeremy Mardon; Adrian Soto; Tomer Volansky; Tien-Tien Yu

    2015-09-04

    Dark matter in the sub-GeV mass range is a theoretically motivated but largely unexplored paradigm. Such light masses are out of reach for conventional nuclear recoil direct detection experiments, but may be detected through the small ionization signals caused by dark matter-electron scattering. Semiconductors are well-studied and are particularly promising target materials because their ${\\cal O}(1~\\rm{eV})$ band gaps allow for ionization signals from dark matter as light as a few hundred keV. Current direct detection technologies are being adapted for dark matter-electron scattering. In this paper, we provide the theoretical calculations for dark matter-electron scattering rate in semiconductors, overcoming several complications that stem from the many-body nature of the problem. We use density functional theory to numerically calculate the rates for dark matter-electron scattering in silicon and germanium, and estimate the sensitivity for upcoming experiments such as DAMIC and SuperCDMS. We find that the reach for these upcoming experiments has the potential to be orders of magnitude beyond current direct detection constraints and that sub-GeV dark matter has a sizable modulation signal. We also give the first direct detection limits on sub-GeV dark matter from its scattering off electrons in a semiconductor target (silicon) based on published results from DAMIC. We make available publicly our code, QEdark, with which we calculate our results. Our results can be used by experimental collaborations to calculate their own sensitivities based on their specific setup. The searches we propose will probe vast new regions of unexplored dark matter model and parameter space.

  15. Activation and thermal stability of ultra-shallow B{sup +}-implants in Ge

    SciTech Connect (OSTI)

    Yates, B. R.; Darby, B. L.; Jones, K. S. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Petersen, D. H. [DTU Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); Hansen, O. [DTU Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); CINF, Center for Individual Nanoparticle Functionality, Technical University of Denmark, DK-2800 Kongens Lyngby (Denmark); Lin, R.; Nielsen, P. F. [CAPRES A/S, Scion-DTU, DK-2800 Kgs. Lyngby (Denmark); Romano, L. [IMM-CNR MATIS and Dipartimento di Fisica e Astronomia, Universita di Catania, Via S. Sofia 64, I-95123 Catania (Italy); Doyle, B. L. [Sandia National Laboratories, MS-1056, Albuquerque, New Mexico 87185 (United States); Kontos, A. [Applied Materials, Gloucester, Massachusetts 01930 (United States)

    2012-12-15

    The activation and thermal stability of ultra-shallow B{sup +} implants in crystalline (c-Ge) and preamorphized Ge (PA-Ge) following rapid thermal annealing was investigated using micro Hall effect and ion beam analysis techniques. The residual implanted dose of ultra-shallow B{sup +} implants in Ge was characterized using elastic recoil detection and was determined to correlate well with simulations with a dose loss of 23.2%, 21.4%, and 17.6% due to ion backscattering for 2, 4, and 6 keV implants in Ge, respectively. The electrical activation of ultra-shallow B{sup +} implants at 2, 4, and 6 keV to fluences ranging from 5.0 Multiplication-Sign 10{sup 13} to 5.0 Multiplication-Sign 10{sup 15} cm{sup -2} was studied using micro Hall effect measurements after annealing at 400-600 Degree-Sign C for 60 s. For both c-Ge and PA-Ge, a large fraction of the implanted dose is rendered inactive due to the formation of a presumable B-Ge cluster. The B lattice location in samples annealed at 400 Degree-Sign C for 60 s was characterized by channeling analysis with a 650 keV H{sup +} beam by utilizing the {sup 11}B(p, {alpha})2{alpha} nuclear reaction and confirmed the large fraction of off-lattice B for both c-Ge and PA-Ge. Within the investigated annealing range, no significant change in activation was observed. An increase in the fraction of activated dopant was observed with increasing energy which suggests that the surface proximity and the local point defect environment has a strong impact on B activation in Ge. The results suggest the presence of an inactive B-Ge cluster for ultra-shallow implants in both c-Ge and PA-Ge that remains stable upon annealing for temperatures up to 600 Degree-Sign C.

  16. An ultra-thin buffer layer for Ge epitaxial layers on Si

    SciTech Connect (OSTI)

    Kawano, M.; Yamada, S.; Tanikawa, K.; Miyao, M.; Hamaya, K. [Department of Electronics, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan)] [Department of Electronics, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan); Sawano, K. [Advanced Research Laboratories, Tokyo City University, 8-15-1 Todoroki, Tokyo 158-0082 (Japan)] [Advanced Research Laboratories, Tokyo City University, 8-15-1 Todoroki, Tokyo 158-0082 (Japan)

    2013-03-25

    Using an Fe{sub 3}Si insertion layer, we study epitaxial growth of Ge layers on a Si substrate by a low-temperature molecular beam epitaxy technique. When we insert only a 10-nm-thick Fe{sub 3}Si layer in between Si and Ge, epitaxial Ge layers can be obtained on Si. The detailed structural characterizations reveal that a large lattice mismatch of {approx}4% is completely relaxed in the Fe{sub 3}Si layer. This means that the Fe{sub 3}Si layers can become ultra-thin buffer layers for Ge on Si. This method will give a way to realize a universal buffer layer for Ge, GaAs, and related devices on a Si platform.

  17. Mn solid solutions in self-assembled Ge/Si (001) quantum dot heterostructures

    SciTech Connect (OSTI)

    Kassim, J.; Nolph, C.; Reinke, P.; Floro, J. [Department of Materials Science and Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States); Jamet, M. [Institut Nanosciences et Cryogenie/SP2M, CEA-UJF, F-38054 Grenoble (France)

    2012-12-10

    Heteroepitaxial Ge{sub 0.98}Mn{sub 0.02} quantum dots (QDs) on Si (001) were grown by molecular beam epitaxy. The standard Ge wetting layer-hut-dome-superdome sequence was observed, with no indicators of second phase formation in the surface morphology. We show that Mn forms a dilute solid solution in the Ge quantum dot layer, and a significant fraction of the Mn partitions into a sparse array of buried, Mn-enriched silicide precipitates directly underneath a fraction of the Ge superdomes. The magnetic response from the ultra-thin film indicates the absence of robust room temperature ferromagnetism, perhaps due to anomalous intermixing of Si into the Ge quantum dots.

  18. The reliability studies of nano-engineered SiGe HBTs using Pelletron accelerator

    SciTech Connect (OSTI)

    Prakash, A. P. Gnana Praveen, K. C.; Pushpa, N.; Cressler, John D.

    2015-05-15

    The effects of high energy ions on the electrical characteristics of silicon-germanium heterojunction bipolar transistors (SiGe HBTs) were studied in the total dose of ranging from 600 krad to 100 Mrad (Si). The two generations (50 GHz and 200 GHz) of SiGe HBTs were exposed to 50 MeV lithium, 75 MeV boron and 100 MeV oxygen ions. The electrical characteristics of SiGe HBTs were studied before and after irradiation. The SiGe HBTs were exposed to {sup 60}Co gamma radiation in the same total dose. The results are systematically compared in order to understand the interaction of ions and ionizing radiation with SiGe HBTs.

  19. Ultra-high frequency photoconductivity decay in GaAs/Ge/GaAs double heterostructure grown by molecular beam epitaxy

    SciTech Connect (OSTI)

    Hudait, M. K.; Zhu, Y. [Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)] [Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States); Johnston, S. W. [National Renewable Energy Laboratory, Golden, Colorado 80401 (United States)] [National Renewable Energy Laboratory, Golden, Colorado 80401 (United States); Maurya, D.; Priya, S. [Center for Energy Harvesting Materials and Systems (CEHMS), Virginia Tech, Blacksburg, Virginia 24061 (United States)] [Center for Energy Harvesting Materials and Systems (CEHMS), Virginia Tech, Blacksburg, Virginia 24061 (United States); Umbel, R. [Materials Science and Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)] [Materials Science and Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)

    2013-03-04

    GaAs/Ge/GaAs double heterostructures (DHs) were grown in-situ using two separate molecular beam epitaxy chambers. High-resolution x-ray rocking curve demonstrates a high-quality GaAs/Ge/GaAs heterostructure by observing Pendelloesung oscillations. The kinetics of the carrier recombination in Ge/GaAs DHs were investigated using photoconductivity decay measurements by the incidence excitation from the front and back side of 15 nm GaAs/100 nm Ge/0.5 {mu}m GaAs/(100)GaAs substrate structure. High-minority carrier lifetimes of 1.06-1.17 {mu}s were measured when excited from the front or from the back of the Ge epitaxial layer, suggests equivalent interface quality of GaAs/Ge and Ge/GaAs. Wavelength-dependent minority carrier recombination properties are explained by the wavelength-dependent absorption coefficient of Ge.

  20. SiGe-free strained Si on insulator by wafer bonding and layer transfer T. A. Langdo,a)

    E-Print Network [OSTI]

    ­8 or Ge condensation during SiGe oxidation.9 In these approaches, the relaxed SGOI layer serves as a ten chemical mechanical polishing step to elimi- nate the surface crosshatch roughness induced by the com

  1. Adjudication Concerning the Erection of Three Temporary Sectional Buildings for the Staff of the 300 GeV Programme

    E-Print Network [OSTI]

    1971-01-01

    Adjudication Concerning the Erection of Three Temporary Sectional Buildings for the Staff of the 300 GeV Programme

  2. Adjudication of the Building Construction Work for the Laboratories and Offices of the 300 GeV Programme

    E-Print Network [OSTI]

    1971-01-01

    Adjudication of the Building Construction Work for the Laboratories and Offices of the 300 GeV Programme

  3. Adjudication Concerning the Civil Engineering Work for the Auxiliary Buildings of the 300 GeV Accelerator

    E-Print Network [OSTI]

    1972-01-01

    Adjudication Concerning the Civil Engineering Work for the Auxiliary Buildings of the 300 GeV Accelerator

  4. Production of isotopes in 1.A GeV $^{208}Pb$ on proton reactions relevant for accelerator-driven systems

    E-Print Network [OSTI]

    Wlazlo, W; Armbruster, P; Benlliure, J; Bernas, M; Boudard, A; Czajkowski, S; Farget, F; Legrain, R; Leray, S; Mustapha, B; Pravikoff, M S; Schmidt, K H; Stéphan, C; Taieb, J; Tassan-Got, L; Volant, C

    1999-01-01

    Production of isotopes in 1.A GeV $^{208}Pb$ on proton reactions relevant for accelerator-driven systems

  5. Photoluminescence from electron-hole plasmas confined in Si/Si 1-,Ge,/Si quantum wells

    E-Print Network [OSTI]

    Photoluminescence from electron-hole plasmas confined in Si/Si 1-,Ge,/Si quantum wells X. Xiao, C 1992) We report the first observation of photoluminescence from electron-hole plasmas in Si/S&,sGe of the physical processes un- derlying luminescence in Si, -,GeX alloys, especially at high carrier densities

  6. Threshold Pressure for Disappearance of Size-Induced Effect in Spinel-Structure Ge3N4 Nanocrystals

    E-Print Network [OSTI]

    Downs, Robert T.

    Threshold Pressure for Disappearance of Size-Induced Effect in Spinel-Structure Ge3N4 Nanocrystals demonstrate that the incompressibility of spinel Ge3N4 nanocrystals decreases when the pressure is elevated above 20 GPa. Ge3N4 nanocrystals initially exhibit a higher bulk modulus of 381(2) GPa. But, above 20

  7. Project #8: Zigang Ge and Robert Guldberg: Cartilage Regeneration with Functional Biomaterials and Quantitative Assessment of Regeneration

    E-Print Network [OSTI]

    Weber, Rodney

    Project #8: Zigang Ge and Robert Guldberg: Cartilage Regeneration with Functional Biomaterials from Georgia Institute of Technology and the GE lab from Peking University. The proposed collaboration the development of effective strategies for functional restoration of degenerated articular joints. Ge's lab

  8. 05Mar09 ANALYSISIn crisis, GE finds its deep bench not so magical By James B. Kelleher

    E-Print Network [OSTI]

    Kuzmanovic, Aleksandar

    05Mar09 ANALYSISIn crisis, GE finds its deep bench not so magical By James B. Kelleher CHICAGO, March 5 (Reuters) Crotonville, we have a problem. The travails of General Electric Co GE and expensive training program credited with creating those managers. In recent weeks, GE executives have

  9. Disordered electronic and magnetic systems - transition metal (Mn) and rare earth (Gd) doped amorphous group IV semiconductors (C, Si, Ge)

    E-Print Network [OSTI]

    Zeng, Li

    2007-01-01

    Magnetization data for a-Mn 0.15 Ge 0.85 ?lms mea- suredSi 1?x and a-Mn x Ge 1?x samples. . . . . . . . . . . . . .both a-Mn x Si 1?x and a-Mn x Ge 1?x as a func- tion of Mn

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

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    A search for GeV-TeV emission from Gamma-ray Bursts using the Milagro detector p. M. Saz Parkinson for >1 GeV emission from these bursts. Milagro is a water Cerenkov detector designed primarily", where the rates of individual photomultiplier tubes can be used to detect emission above 1 GeV (albeit

  11. The electrical and material properties of strained SiGe alloys have been overviewed and the historical sur-

    E-Print Network [OSTI]

    Rieh, Jae-Sung

    semiconductor materials. The Table 1. Selected properties of bulk Si and Ge at 300K[1]. Property Si Ge CrystalAbstract The electrical and material properties of strained SiGe alloys have been overviewed systems. In the past, III-V semiconductor-based systems were deemed to be most suitable for high

  12. Study of plutonium disposition using the GE Advanced Boiling Water Reactor (ABWR)

    SciTech Connect (OSTI)

    1994-04-30

    The end of the cold war and the resulting dismantlement of nuclear weapons has resulted in the need for the U.S. to disposition 50 to 100 metric tons of excess of plutonium in parallel with a similar program in Russia. A number of studies, including the recently released National Academy of Sciences (NAS) study, have recommended conversion of plutonium into spent nuclear fuel with its high radiation barrier as the best means of providing long-term diversion resistance to this material. The NAS study {open_quotes}Management and Disposition of Excess Weapons Plutonium{close_quotes} identified light water reactor spent fuel as the most readily achievable and proven form for the disposition of excess weapons plutonium. The study also stressed the need for a U.S. disposition program which would enhance the prospects for a timely reciprocal program agreement with Russia. This summary provides the key findings of a GE study where plutonium is converted into Mixed Oxide (MOX) fuel and a 1350 MWe GE Advanced Boiling Water Reactor (ABWR) is utilized to convert the plutonium to spent fuel. The ABWR represents the integration of over 30 years of experience gained worldwide in the design, construction and operation of BWRs. It incorporates advanced features to enhance reliability and safety, minimize waste and reduce worker exposure. For example, the core is never uncovered nor is any operator action required for 72 hours after any design basis accident. Phase 1 of this study was documented in a GE report dated May 13, 1993. DOE`s Phase 1 evaluations cited the ABWR as a proven technical approach for the disposition of plutonium. This Phase 2 study addresses specific areas which the DOE authorized as appropriate for more in-depth evaluations. A separate report addresses the findings relative to the use of existing BWRs to achieve the same goal.

  13. Azimuthal correlations of transverse energy for Pb on Pb at 158 GeV/nucleon

    SciTech Connect (OSTI)

    Wienold, T. [Lawrence Berkeley National Lab., CA (United States); Huang, I. [California Univ., Davis, CA (United States); The NA49 Collaboration

    1996-02-03

    Azimuthal correlations have been studied in heavy ion reactions over a wide range of beam energies. At low incident energies up to 100 MeV/nucleon where collective effects like the directed sidewards flow are generally small, azimuthal correlations provide a useful tool to determine the reaction plane event by event. In the energy regime of the BEVALAC (up to 1 GeV/nucleon for heavy ions) particular emission patterns, i.e. azimuthal correlations of nucleons and light nuclei with respect to the reaction plane, have been associated with the so called squeeze out and sidesplash effects. These effects are of particular interest because of their sensitivity to the equation of state at the high baryon density which is build up during the collision process. Angular distributions similar to the squeeze out have been observed for pions at the SIS in Darmstadt as well as from the EOS - collaboration. Recently also the sideward flow was measured for pions and kaons. However, the origin of the signal in the case of produced mesons is thought to be of a different nature than that for the nucleon flow. At the AGS, azimuthally anisotropic event shapes have been reported from the E877 collaboration for the highest available heavy ion beam energy (11.4 GeV/nucleon). Using a Fourier analysis of the transverse energy distribution measured in calorimeters, it was concluded that sideward flow is still of significant magnitude. Here we will report a first analysis of azimuthal correlations found in the transverse energy distribution from Pb on Pb collisions at the CERN SPS (158 GeV/nucleon).

  14. Density functional theory calculations of stability and diffusion mechanisms of impurity atoms in Ge crystals

    SciTech Connect (OSTI)

    Maeta, Takahiro; Sueoka, Koji

    2014-08-21

    Ge-based substrates are being developed for applications in advanced nano-electronic devices because of their higher intrinsic carrier mobility than Si. The stability and diffusion mechanism of impurity atoms in Ge are not well known in contrast to those of Si. Systematic studies of the stable sites of 2nd to 6th row element impurity atoms in Ge crystal were undertaken with density functional theory (DFT) and compared with those in Si crystal. It was found that most of the impurity atoms in Ge were stable at substitutional sites, while transition metals in Si were stable at interstitial sites and the other impurity atoms in Si were stable at substitutional sites. Furthermore, DFT calculations were carried out to clarify the mechanism responsible for the diffusion of impurity atoms in Ge crystals. The diffusion mechanism for 3d transition metals in Ge was found to be an interstitial-substitutional diffusion mechanism, while in Si this was an interstitial diffusion mechanism. The diffusion barriers in the proposed diffusion mechanisms in Ge and Si were quantitatively verified by comparing them to the experimental values in the literature.

  15. Hydrogen Sensor Based on Pd/GeO{sub 2} Using a Low Cost Electrochemical Deposition

    SciTech Connect (OSTI)

    Jawad, M. J.; Hashim, M. R.; Ali, N. K.

    2011-05-25

    This work reports on a synthesis of sub micron germanium dioxide (GeO{sub 2}) on porous silicon (PS) by electrochemical deposition. n-type Si (100) wafer was used to fabricate (PS) using conventional method of electrochemical etching in HF based solution. A GeCl{sub 4} was directly hydrolyzed by hydrogen peroxide to produce pure GeO{sub 2}, and then electrochemically deposited on PS. Followed by palladium (Pd) contact on GeO{sub 2} /PS was achieved by using RF sputtering technique. The grown GeO{sub 2} crystals were characterized using SEM and EDX. I-V characteristics of Pd/ GeO{sub 2} were recorded before and after hydrogen gas exposure as well as with different H{sub 2} concentrations and different applied temperatures. The sensitivity of Pd/ GeO{sub 2} also has been investigated it could be seen to increase significantly with increased hydrogen concentration while it decreased with increase temperature.

  16. Tuning the properties of Ge-quantum dots superlattices in amorphous silica matrix through deposition conditions

    SciTech Connect (OSTI)

    Pinto, S. R. C.; Ramos, M. M. D.; Gomes, M. J. M.; Buljan, M.; Chahboun, A.; Roldan, M. A.; Molina, S. I.; Bernstorff, S.; Varela, M.; Pennycook, S. J.; Barradas, N. P.; Alves, E.

    2012-04-01

    In this work, we investigate the structural properties of Ge quantum dot lattices in amorphous silica matrix, prepared by low-temperature magnetron sputtering deposition of (Ge+SiO{sub 2})/SiO{sub 2} multilayers. The dependence of quantum dot shape, size, separation, and arrangement type on the Ge-rich (Ge + SiO{sub 2}) layer thickness is studied. We show that the quantum dots are elongated along the growth direction, perpendicular to the multilayer surface. The size of the quantum dots and their separation along the growth direction can be tuned by changing the Ge-rich layer thickness. The average value of the quantum dots size along the lateral (in-plane) direction along with their lateral separation is not affected by the thickness of the Ge-rich layer. However, the thickness of the Ge-rich layer significantly affects the quantum dot ordering. In addition, we investigate the dependence of the multilayer average atomic composition and also the quantum dot crystalline quality on the deposition parameters.

  17. Energy (GeV) dN/dE(ergcm2

    E-Print Network [OSTI]

    Nishikawa, Ken-Ichi

    Energy (GeV) -1 10 1 10 2 10 )-1 s-2 dN/dE(ergcm2 E -12 10 -11 10 -10 10 PSR J0007+7303 Full Band Fit (PLEC1) Energy Band Fits #12;Energy (GeV) -1 10 1 10 2 10 )-1 s-2 dN/dE(ergcm2 E -12 10 PSR J0023+0923 Full Band Fit (PLEC1) Energy Band Fits #12;Energy (GeV) -1 10 1 10 2 10 )-1 s-2 dN/dE(ergcm2 E -12 10

  18. Characterization of SiGe/Si multi-quantum wells for infrared sensing

    SciTech Connect (OSTI)

    Moeen, M.; Salemi, A.; Östling, M.; Radamson, H. H., E-mail: rad@kth.se [School of Information and Communication Technology, KTH Royal Institute of Technology, Stockholm, 16640 Kista (Sweden); Kolahdouz, M. [School of Electrical and Computer Engineering, University of Tehran, Tehran (Iran, Islamic Republic of)] [School of Electrical and Computer Engineering, University of Tehran, Tehran (Iran, Islamic Republic of)

    2013-12-16

    SiGe epitaxial layers are integrated as an active part in thermal detectors. To improve their performance, deeper understanding of design parameters, such as thickness, well periodicity, quality, and strain amount, of the layers/interfaces is required. Oxygen (2–2500?×?10{sup ?9}?Torr) was exposed prior or during epitaxy of SiGe/Si multilayers. In this range, samples with 10?nTorr oxygen were processed to investigate layer quality and noise measurements. Temperature coefficient of resistance was also measured to evaluate the thermal response. These results demonstrate sensitivity of SiGe-based devices to size and location of defects in the structure.

  19. Roles of Oxygen and Water Vapor in the Oxidation of Halogen Terminated Ge(111) Surfaces

    SciTech Connect (OSTI)

    Sun, Shiyu; /Stanford U., Phys. Dept.; Sun, Yun; Liu, Zhi; Lee, Dong-Ick; Pianette, Piero; /SLAC, SSRL

    2006-12-18

    The initial stage of the oxidation of Cl and Br terminated Ge(111) surfaces is studied using photoelectron spectroscopy. The authors perform controlled experiments to differentiate the effects of different factors in oxidation, and find that water vapor and oxygen play different roles. Water vapor effectively replaces the halogen termination layers with the hydroxyl group, but does not oxidize the surfaces further. In contrast, little oxidation is observed for Cl and Br terminated surfaces with dry oxygen alone. However, with the help of water vapor, oxygen oxidizes the surface by breaking the Ge-Ge back bonds instead of changing the termination layer.

  20. Spectral analysis of Fermi-LAT blazars above 50 GeV

    E-Print Network [OSTI]

    Domínguez, Alberto

    2015-01-01

    We present an analysis of the intrinsic (unattenuated by the extragalactic background light, EBL) power-law spectral indices of 128 extragalactic sources detected up to z~2 with the Fermi-Large Area Telescope (LAT) at very high energies (VHEs, E>50 GeV). The median of the intrinsic index distribution is 2.20 (versus 2.54 for the observed distribution). We also analyze the observed spectral breaks (i.e., the difference between the VHE and high energy, HE, 100 MeVGeV, spectral indices). The LAT has now provided a large sample of sources detected both at VHE and HE with comparable exposure that allows us to test models of extragalactic gamma-ray photon propagation. We find that our data are compatible with simulations that include intrinsic blazar curvature and EBL attenuation. There is also no evidence of evolution with redshift of the physics that drives the photon emission in high-frequency synchrotron peak (HSP) blazars. This makes HSP blazars excellent probes of the EBL.

  1. Right-handed neutrino production rate at T > 160 GeV

    SciTech Connect (OSTI)

    Ghisoiu, I.; Laine, M. E-mail: laine@itp.unibe.ch

    2014-12-01

    The production rate of right-handed neutrinos from a Standard Model plasma at a temperature above a hundred GeV has previously been evaluated up to NLO in Standard Model couplings (g ? 2/3) in relativistic (M ? ?T) and non-relativistic regimes (M >> ?T), and up to LO in an ultrarelativistic regime (M ?< gT). The last result necessitates an all-orders resummation of the loop expansion, accounting for multiple soft scatterings of the nearly light-like particles participating in 1 ? 2 reactions. In this paper we suggest how the regimes can be interpolated into a result applicable for any right-handed neutrino mass and at all temperatures above 160GeV. The results can also be used for determining the lepton number washout rate in models containing right-handed neutrinos. Numerical results are given in a tabulated form permitting for their incorporation into leptogenesis codes. We note that due to effects from soft Higgs bosons there is a narrow intermediate regime around (M ? g{sup 1/2}T in which our interpolation is phenomenological and a more precise study would be welcome.

  2. Early Commissioning Experience and Future Plans for the 12 GeV Continuous Electron Beam Accelerator Facility

    SciTech Connect (OSTI)

    Spata, Michael F.

    2014-12-01

    Jefferson Lab has recently completed the accelerator portion of the 12 GeV Upgrade for the Continuous Electron Beam Accelerator Facility. All 52 SRF cryomodules have been commissioned and operated with beam. The initial beam transport goals of demonstrating 2.2 GeV per pass, greater than 6 GeV in 3 passes to an existing experimental facility and greater than 10 GeV in 5-1/2 passes have all been accomplished. These results along with future plans to commission the remaining beamlines and to increase the performance of the accelerator to achieve reliable, robust and efficient operations at 12 GeV are presented.

  3. Photoproduction of eta mesons off protons for photon energies from 0.75 GeV to 3 GeV

    E-Print Network [OSTI]

    Volker Crede; Olivia Bartholomy; for the CB-ELSA Collaboration

    2004-10-20

    Total and differential cross sections for the reaction p(gamma, eta)p have been measured for photon energies in the range from 750 MeV to 3 GeV. The low-energy data are dominated by the S11 wave which has two poles in the energy region below 2 GeV. Eleven nucleon resonances are observed in their decay into p eta. At medium energies we find evidence for a new resonance N(2070)D15 with (mass, width) = (2068+-22, 295+-40) MeV. At photon energies above 1.5 GeV, a strong peak in forward direction develops, signalling the exchange of vector mesons in the t channel.

  4. Investigation of high temperature gaseous species by Knudsen cell mass spectrometry above the condensed systems Au-Ge-Cu and Au-Si / by Joseph Edward Kingcade 

    E-Print Network [OSTI]

    Kingcade, Joseph Edward

    1978-01-01

    '. ;A2) i Relative Intensity Nultiplier Gain Correction Factor E Au i Calibration Constant atm/A-K Au + Au 2 Cu + Cu~ Ge+ Ce 2. Ge3 Ge4 AuCu CuGe CuGe2 AuGe ' Au2 Ge + AuGe2 8. 7 + 0. 6 n, d, n. d. n. d. n. d. 10. 1 + 0. 6 n... Appearance Potential ( eV ) Ionization Cross Sections 0 i Pelative Intensity Multiplier Gain Correction Factor +1/g' E Au i Calibration Constant atm/A-K Au2Ge2 + AuGe3" AuGe4 n. d. n. d. n. d 17. 34 17. 23 21. 52 1. 19 l. 28 l. 28 l...

  5. Effects of boron dopants of Si (001) substrates on formation of Ge layers by sputter epitaxy method

    SciTech Connect (OSTI)

    Tsukamoto, Takahiro; Suda, Yoshiyuki [Graduate School of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588 (Japan)] [Graduate School of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588 (Japan); Hirose, Nobumitsu; Kasamatsu, Akifumi; Mimura, Takashi; Matsui, Toshiaki [National Institute of Information and Communications Technology, 4-2-1 Nukui-Kitamachi, Koganei, Tokyo 184-8795 (Japan)] [National Institute of Information and Communications Technology, 4-2-1 Nukui-Kitamachi, Koganei, Tokyo 184-8795 (Japan)

    2013-10-21

    The formation of Ge layers on boron-doped Si (001) substrates by our sputter epitaxy method has been investigated. The surface morphology of Ge layers grown on Si substrates depends on the substrate resistance, and flat Ge layers are obtained on Si substrates with 0.015 ? cm resistivity. Highly boron-doped Si substrates cause a transition in the dislocation structure from complex dislocations with 60° dislocation glide planes to 90° pure-edge dislocations, resulting in the formation of flat Ge layers. Furthermore, we have found that the surface morphology of the Ge layers improves with increasing Ge layer thickness. Ge atoms migrating on the deposited Ge layers tend to position themselves at the reactive sites, where the reactivity is related to the number of bonding contacts between the Ge atom and the surface. This modifies the surface morphology, resulting in a flatter surface. Boron dopants together with the sputter epitaxy method effectively suppress the growth of Ge islands and result in the formation of flat Ge layers.

  6. Thermoelectric infrared microsensors based on a periodically suspended thermopile integrating nanostructured Ge/SiGe quantum dots superlattice

    SciTech Connect (OSTI)

    Ziouche, K. E-mail: Zahia.bougrioua@iemn.univ-lille1.fr; Bougrioua, Z. E-mail: Zahia.bougrioua@iemn.univ-lille1.fr; Lejeune, P.; Lasri, T.; Leclercq, D.; Savelli, G.; Hauser, D.; Michon, P.-M.

    2014-07-28

    This paper presents an original integration of polycrystalline SiGe-based quantum dots superlattices (QDSL) into Thermoelectric (TE) planar infrared microsensors (?SIR) fabricated using a CMOS technology. The nanostructuration in QDSL results into a considerably reduced thermal conductivity by a factor up to 10 compared to the one of standard polysilicon layers that are usually used for IR sensor applications. A presentation of several TE layers, QDSL and polysilicon, is given before to describe the fabrication of the thermopile-based sensors. The theoretical values of the sensitivity to irradiance of ?SIR can be predicted thanks to an analytical model. These findings are used to interpret the experimental measurements versus the nature of the TE layer exploited in the devices. The use of nanostructured QDSL as the main material in ?SIR thermopile has brought a sensitivity improvement of about 28% consistent with theoretical predictions. The impact of QDSL low thermal conductivity is damped by the contribution of the thermal conductivity of all the other sub-layers that build up the device.

  7. Super-dense array of Ge quantum dots grown on Si(100) by low-temperature molecular beam epitaxy

    SciTech Connect (OSTI)

    Talochkin, A. B., E-mail: tal@isp.nsc.ru; Shklyaev, A. A. [A.V. Rzhanov Institute of Semiconductor Physics, Lavrentyev Avenue 13, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Mashanov, V. I. [A.V. Rzhanov Institute of Semiconductor Physics, Lavrentyev Avenue 13, Novosibirsk 630090 (Russian Federation)

    2014-04-14

    Ge layer grown on Si(100) at the low temperature of ?100?°C by molecular beam epitaxy is studied using scanning tunneling microscopy and Raman spectroscopy. It is found that crystalline and pseudomorphic to the Si substrate Ge islands are formed at the initial growth stage. The islands acquire the base size of 1.2–2.6?nm and they form arrays with the super-high density of (5–8)?×?10{sup 12}?cm{sup ?2} at 1–2?nm Ge coverages. Such a density is at least 10 times higher than that of Ge “hut” clusters grown via the Stranski-Krastanov growth mode. It is shown that areas between the crystalline Ge islands are filled with amorphous Ge, which is suggested to create potential barrier for holes localized within the islands. As a result, crystalline Ge quantum dots appear being isolated from each other.

  8. Antimony segregation in stressed SiGe heterostructures grown by molecular beam epitaxy

    SciTech Connect (OSTI)

    Drozdov, M. N.; Novikov, A. V.; Yurasov, D. V., E-mail: Inquisitor@ipm.sci.nnov.ru [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)

    2013-11-15

    The effects of the growth temperature, composition, and elastic strains in separate layers on the segregation of antimony are studied experimentally for stressed SiGe structures grown by molecular beam epitaxy. It is established that the growth conditions and parameters of the structures exert an interrelated influence on the segregation of Sb: the degree of the influence of the composition and elastic stresses in the SiGe layers on Sb segregation depends on the growth temperature. It is shown that usage of a method previously proposed by us for the selective doping of silicon structures with consideration for the obtained dependences of Sb segregation on the growth conditions and parameters of the SiGe layers makes it possible to form SiGe structures selectively doped with antimony.

  9. Modeling analysis of core-shell Si/SiGe nanowires

    E-Print Network [OSTI]

    Tang, Ming Y., 1979-

    2004-01-01

    (cont.) a composition that results in a high mobility has a very promising thermoelectric performance. Lastly, the thermoelectric-related transport properties for a Si/SiGe core-shell nanowire are compared with the related ...

  10. Ge-on-Si Integrated Photonics: New Tricks from an Old Semiconductor

    E-Print Network [OSTI]

    Jifeng, Liu

    We review recent progress in Ge active photonic devices for electronic-photonic integration on Si, demonstrating new tricks in optoelectronics from this “old” semiconductor material used for the first transistor more than ...

  11. High hole and electron mobilities using Strained Si/Strained Ge heterostructures

    E-Print Network [OSTI]

    Gupta, Saurabh

    PMOS and NMOS mobility characteristics of the dual channel (strained Si/strained Ge) heterostructure have been reviewed. It is shown that the dual channel heterostructure can provide substantially enhanced mobilities for ...

  12. Investigation of crystalline and electronic band alignment properties of GaP/Ge(111) heterostructure

    SciTech Connect (OSTI)

    Dixit, V. K.; Kumar, Shailendra; Singh, S. D.; Khamari, S. K.; Kumar, R.; Tiwari, Pragya; Sharma, T. K.; Oak, S. M. [Raja Ramanna Centre for Advanced Technology, Indore, Madhya Pradesh 452013 (India); Phase, D. M. [UGC-DAE Consortium for Scientific Research, Khandwa Road, Indore, Madhya Pradesh 452001 (India)

    2014-03-03

    Gallium phosphide (GaP) epitaxial layer and nanostructures are grown on n-Ge(111) substrates using metal organic vapour phase epitaxy. It is confirmed by high resolution x-ray diffraction measurements that the layer is highly crystalline and oriented with the coexistence of two domains, i.e., GaP(111)A and GaP(111)B, with an angle of 60° between them due to the formation of a wurtzite monolayer at the interface. The valence band offset between GaP and Ge is 0.7?±?0.1?eV as determined from the valence band onsets and from Kraut's method. A band alignment diagram for GaP/Ge/GeOx is also constructed which can be used to design monolithic optoelectronic integrated circuits.

  13. Surface-induced charge at the Ge (001) surface and its interaction with self-interstitials

    SciTech Connect (OSTI)

    Kamiyama, Eiji; Sueoka, Koji [Department of Communication Engineering, Okayama Prefectural University, 111 Kuboki, Soja-shi, Okayama-ken 719-1197 (Japan); Vanhellemont, Jan [Department of Solid State Sciences, Ghent University, B-9000 Gent (Belgium)

    2014-02-21

    The Ge (001) surface with dimer structure, is negatively charged while into the bulk, positive charges are observed even deeper than the fifteenth layer from the surface. This is different from the Si case. This charge distribution can lead to the repulsion of positively charged self-interstitials by the positively charged near surface layer in an implantation or irradiation process. Self-interstitial reflection by Ge surfaces had been proposed to explain the results of diffusion experiments during irradiation whereby positively charged self-interstitials are generated by collisions of highly energetic particles with Ge atoms. We investigated different Ge (001) surface comparing an as-cleaved surface with dangling bonds to a surface with dimer structure, and to a surface terminated by hydrogen atoms. The effect of these different surface terminations on the surface-induced charges in the near surface bulk were calculated by ab initio techniques.

  14. AVTA: GE Energy WattStation AC Level 2 Charging System Testing...

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

    Energy WattStation AC Level 2 Charging System Testing Results AVTA: GE Energy WattStation AC Level 2 Charging System Testing Results The Vehicle Technologies Office's Advanced...

  15. Direct gap photoluminescence of n-type tensile-strained Ge-on-Si

    E-Print Network [OSTI]

    Sun, Xiaochen

    Room temperature direct gap photoluminescence (PL) was observed from n-type tensile-strained epitaxial Ge-on-Si. The PL intensity increases with n-type doping due to a higher electron population in the direct ? valley as ...

  16. Duality invariance of $s \\ge 3/2$ fermions in AdS

    E-Print Network [OSTI]

    S. Deser; D. Seminara

    2014-09-11

    We show that in D=4 AdS, $s\\ge 3/2$ partially massless (PM) fermions retain the duality invariances of their flat space massless counterparts. They have tuned ratios $ {m^2}/{M^2}\

  17. Effect of tensile strain on the electronic structure of Ge: A first-principles calculation

    SciTech Connect (OSTI)

    Liu, Li [Key Laboratory for Microstructures and Institute of Materials Science, Shanghai University, Shanghai 200072 (China); State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Zhang, Miao; Di, Zengfeng, E-mail: zfdi@mail.sim.ac.cn, E-mail: shijin.zhao@shu.edu.cn [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Hu, Lijuan; Zhao, Shi-Jin, E-mail: zfdi@mail.sim.ac.cn, E-mail: shijin.zhao@shu.edu.cn [Key Laboratory for Microstructures and Institute of Materials Science, Shanghai University, Shanghai 200072 (China)

    2014-09-21

    Taking the change of L-point conduction band valley degeneracy under strain into consideration, we investigate the effect of biaxially tensile strain (parallel to the (001), (110), and (111) planes) and uniaxially tensile strain (along the [001], [110], and [111] directions) on the electronic structure of Ge using density functional theory calculations. Our calculation shows that biaxial tension parallel to (001) is the most efficient way to transform Ge into a direct bandgap material among all tensile strains considered. [111]-tension is the best choice among all uniaxial approaches for an indirect- to direct-bandgap transition of Ge. The calculation results, which are further elaborated by bond-orbital approximation, provide a useful guidance on the optical applications of Ge through strain engineering.

  18. A Ge-on-Si laser for electronic-photonic integration

    E-Print Network [OSTI]

    Sun, Xiaochen

    We demonstrate room temperature photoluminescence and optical gain from the direct band gap transition of tensile strained n-type Ge-on-Si around 1600 nm, which can be applied to a Si-based laser for optical interconnects ...

  19. One-step aluminium-assisted crystallization of Ge epitaxy on Si by magnetron sputtering

    SciTech Connect (OSTI)

    Liu, Ziheng, E-mail: ziheng.liu@unsw.edu.au; Hao, Xiaojing; Ho-Baillie, Anita; Green, Martin A. [School of Photovoltaic and Renewable Energy Engineering, University of New South Wales, Sydney 2052 (Australia)

    2014-02-03

    In this work, one-step aluminium-assisted crystallization of Ge on Si is achieved via magnetron sputtering by applying an in-situ low temperature (50?°C to 150?°C) heat treatment in between Al and Ge depositions. The effect of heat treatment on film properties and the growth mechanism of Ge epitaxy on Si are studied via X-ray diffraction, Raman and transmission electron microscopy analyses. Compared with the conventional two-step process, the one-step aluminium-assisted crystallization requires much lower thermal budget and results in pure Ge epitaxial layer, which may be suitable for use as a virtual substrate for the fabrication of III-V solar cells.

  20. Jefferson Lab to Mark the End of CEBAF 6 GeV Operations on May...

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

    18 CEBAFAerial.jpg Jefferson Lab will officially end 6 GeV operations of the Continuous Electron Beam Accelerator Facility during a short ceremony planned for May 18 in the...

  1. GeV electron beams from a laser-plasma accelerator

    E-Print Network [OSTI]

    2008-01-01

    S. M. Hooker, “Gev electron beams from a centimetre-scaleproducing monoenergetic electron beams,” Nature, vol. 431,GeV electron beams from a laser-plasma accelerator C. B.

  2. SiGe integrated circuits for millimeter-wave imaging and phased arrays

    E-Print Network [OSTI]

    May, Jason W.

    2009-01-01

    b) associated with LNA 2 utilizes a “fast” foundry processwave detection in a foundry CMOS process,” IEEE ElectronSiGe BiCMOS HBT Comparison Foundry Process f t , GHz f max ,

  3. The Capabilities of the Alpha Magnetic Spectrometer as GeV Gamma-rays Detector

    E-Print Network [OSTI]

    R. Battiston

    1999-11-13

    The modeled performance of the Alpha Magnetic Spectrometer (AMS) as a high-energy (0.3 to 100 GeV) gamma-ray detector is described, and its gamma-ray astrophysics objectives are discussed.

  4. Control of Laser Plasma Based Accelerators up to 1 GeV

    E-Print Network [OSTI]

    Nakamura, Kei

    2008-01-01

    The main e-beam diagnostic, namely the GeV class electronof a diagnostic for the e-beam, namely an electronby the laser pulse diagnostics. Electron Beam Generation As

  5. A market analysis for high efficiency multi-junction solar cells grown on SiGe

    E-Print Network [OSTI]

    Judkins, Zachara Steele

    2007-01-01

    Applications, markets and a cost model are presented for III-V multi-junction solar cells built on compositionally graded SiGe buffer layers currently being developed by professors Steven Ringell of Ohio State University ...

  6. Using 3D Printing to Redesign Santa's Sleigh | GE Global Research

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

    In the past, we've utilized GE technology to redesign Santa's Sleigh and have asked our additive manufacturing researchers to design and print 3D printed Christmas tree...

  7. A View of Manufacturing Through 3D Glasses | GE Global Research

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

    a.m. Eastern Time, I will be moderating a Google+ Video Hangout with top experts in the additive manufacturing space, which you can view on GE Global Research Live. I will be...

  8. How Career Development Brought Me Back to Legos | GE Global Research

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

    direct write2square The GE Store for Technology is Open for Business 2-4-13-v-3d-printing-medical-devices Invention Factory: How Will The World Get Smaller? ...

  9. Black GE based on crystalline/amorphous core/shell nanoneedle arrays

    DOE Patents [OSTI]

    Javey, Ali; Chueh, Yu-Lun; Fan, Zhiyong

    2014-03-04

    Direct growth of black Ge on low-temperature substrates, including plastics and rubber is reported. The material is based on highly dense, crystalline/amorphous core/shell Ge nanoneedle arrays with ultrasharp tips (.about.4 nm) enabled by the Ni catalyzed vapor-solid-solid growth process. Ge nanoneedle arrays exhibit remarkable optical properties. Specifically, minimal optical reflectance (<1%) is observed, even for high angles of incidence (.about.75.degree.) and for relatively short nanoneedle lengths (.about.1 .mu.m). Furthermore, the material exhibits high optical absorption efficiency with an effective band gap of .about.1 eV. The reported black Ge can have important practical implications for efficient photovoltaic and photodetector applications on nonconventional substrates.

  10. Ge{sub 1-x}Mn{sub x} heteroepitaxial quantum dots: Growth, morphology, and magnetism

    SciTech Connect (OSTI)

    Kassim, J.; Nolph, C.; Reinke, P.; Floro, J. [Department of Materials Science and Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States); Jamet, M. [Institut Nanosciences et Cryogenie/SP2M, CEA-UJF, F-38054 Grenoble (France)

    2013-02-21

    Heteroepitaxial Ge{sub 1-x}Mn{sub x} quantum dots (QDs) were grown on Si (001) by molecular beam epitaxial co-deposition, with x = 0 to 0.10, in order to explore the interaction between Mn content, surface morphological evolution, and magnetism. Morphological evolution typical of the Ge/Si (001) system was observed, where the effect of Mn on surface morphology is surprisingly minimal at low Mn content, with no obvious surface morphological indicators of second phase formation. As the Mn content increases, secondary phase formation becomes evident, appearing to heterogeneously nucleate on or within Ge QDs. Still higher Mn concentrations lead to extensive second phase formation interspersed with an array of Ge QDs. Although ferromagnetism up to 220 K is observed, likely arising from intermetallic precipitates, there is no clear evidence for room-temperature ferromagnetism associated with a dilute magnetic solution phase.

  11. Optical gain and lasing from band-engineered Ge-on-Si at room temperature

    E-Print Network [OSTI]

    Liu, Jifeng

    We present theoretical modeling and experimental results of optical gain and lasing from tensile-strained, n[superscript +] Ge-on-Si at room temperature. Compatible with silicon CMOS, these devices are ideal for large-scale ...

  12. Investigation of lateral gated quantum devices in Si/SiGe heterostructures

    E-Print Network [OSTI]

    Lai, Andrew P. (Andrew Pan)

    2013-01-01

    Quantum dots in Si/SiGe have long spin decoherence times, due to the low density of nuclear spins and weak coupling between nuclear and electronic spins. Because of this, they are excellent candidates for use as solid state ...

  13. A drone's-eye view of a wind turbine | GE Global Research

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

    the innovative ecoROTR wind turbine in a drone GE spent a week flying state-of-the-art drones over and around some of our biggest machines, including the ecoROTR experimental wind...

  14. €18.5 Million in New Research Program Funding Announced, GE...

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

    Funding Announced as GE Marks the 10th Anniversary of its Global Research Center in Europe Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new...

  15. Interaction of Sn atoms with defects introduced by ion implantation in Ge substrate

    SciTech Connect (OSTI)

    Taoka, Noriyuki, E-mail: ntaoka@alice.xtal.nagoya-u.ac.jp; Fukudome, Motoshi; Takeuchi, Wakana; Arahira, Takamitsu; Sakashita, Mitsuo; Nakatsuka, Osamu; Zaima, Shigeaki [Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan)

    2014-05-07

    The interaction of Sn atoms with defects induced by Sn implantation of Ge substrates with antimony (Sb) as an n-type dopant and the impact of H{sub 2} annealing on these defects were investigated by comparison with defects induced by Ge self-implantation. In the Ge samples implanted with either Sn or Ge, and annealed at temperatures of less than 200?°C, divacancies, Sb-vacancy complexes with single or double acceptor-like states, and defects related to Sb and interstitial Ge atoms were present. On the other hand, after annealing at 500?°C in an N{sub 2} or H{sub 2} atmosphere, defects with different structures were observed in the Sn-implanted samples by deep level transition spectroscopy. The energy levels of the defects were 0.33?eV from the conduction band minimum and 0.55?eV from the valence band maximum. From the capacitance-voltage (C-V) characteristics, interaction between Sn atoms and defects after annealing at 500?°C was observed. The effect of H{sub 2} annealing at around 200?°C was observed in the C-V characteristics, which can be attributed to hydrogen passivation, and this effect was observed in both the Ge- and Sn-implanted samples. These results suggest the presence of defects that interact with Sn or hydrogen atoms. This indicates the possibility of defect control in Ge substrates by Sn or hydrogen incorporation. Such defect control could yield high-performance Ge-based devices.

  16. GeV electron beams from a centimetre-scale accelerator

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    GeV electron beams from a centimetre-scale accelerator W. P. LEEMANS1 * , B. NAGLER1 , A. J-quality electron beam with 1 GeV energy by channelling a 40 TW peak-power laser pulse in a 3.3-cm-long gas-100 GV m-1 in laser-wakefield accelerators1,2 , until recently the electron beams (e-beams) from

  17. GeV electron beams from a centimetre-scale accelerator

    E-Print Network [OSTI]

    Loss, Daniel

    LETTERS GeV electron beams from a centimetre-scale accelerator W. P. LEEMANS1 * , B. NAGLER1 , A. J be needed to reach GeV energies6,7 , here we demonstrate production of a high-quality electron beam with 1 in laser-wakefield accelerators1,2 , until recently the electron beams (e-beams) from such accelerators had

  18. Delay Time ConstantAnalysis for5 Optimization in RF Si/SiGeBipolar Devices

    E-Print Network [OSTI]

    Ng, Wai Tung

    Delay Time ConstantAnalysis for5 Optimization in RF Si/SiGeBipolar Devices I-S.M. Sun,H. E. Xu, R, the optimization of the SiGe epitaxial base, intrinsic collector and base doping profiles, and extrinsic collector restrict the degrees of freedom in device optimization. Furthermore, T S . M. Sun, H.E. Xu, R Tam and W. T

  19. Influence of Y substitutions on the magnetism of Gd5Ge4

    SciTech Connect (OSTI)

    Paudyal, Durga; Mudryk, Y.; Pecharsky, V.K.; Misra, S.; Miller, G.J.; and Gschneidner, Jr., K.A.

    2010-04-21

    The interrelation between the specific crystallographic positions and their influence on the magnetism of neighboring atoms is examined from first principles electronic structure calculations using the Gd{sub 5}Ge{sub 4} compound as a model system. The predicted preferences of the specific occupations by nonmagnetic yttrium atoms and the resulting magnetism of substituted Gd{sub 5}Ge{sub 4} have been confirmed, respectively, by single crystal x-ray diffraction and magnetization experiments.

  20. Strangelet search in S-W collisions at 200[ital A] GeV/[ital c

    SciTech Connect (OSTI)

    Borer, K.; Dittus, F.; Frei, D.; Hugentobler, E.; Klingenberg, R.; Moser, U.; Pretzl, K.; Schacher, J.; Stoffel, F.; Volken, W. ); Elsener, K.; Lohmann, K.D. ); Baglin, C.; Bussiere, A.; Guillaud, J.P. ); Appelquist, G.; Bohm, C.; Hovander, B.; Sellden, B.; Zhang, Q.P. )

    1994-03-07

    A search for new massive particles with a low charge to mass ratio in S-W collisions at a beam momentum of 200 GeV/[ital c] per nucleon is presented. Upper limits for the production of strangelets with a mass to charge ratio of up to 60 GeV/[ital c][sup 2] at rigidities of [plus minus]150 GV are reported.

  1. Early diagenesis of germanium in sediments of the Antarctic South Atlantic: In search of the missing Ge sink

    SciTech Connect (OSTI)

    King, S.L.; Froelich, P.N.; Jahnke, R.A.

    2000-04-01

    Pore water and solid-phase geochemistry profiles were obtained from several cores between 41{degree}S and 53{degree}S in the Atlantic sector of the Southern Ocean. Pore water nitrate, manganese, and iron profiles delineate standard redox zones in these sediments, and help characterize those with classic vs. burn-down behaviors. Pore water Si and Ge profiles demonstrate that Ge released during opal dissolution is removed pervasively throughout the uppermost interval of silicate release, and also downwards into the suboxic zone by as yet unidentified precipitation mechanisms. These results indicate that early diagenesis of Ge is uncoupled from that of opal. Solid-phase extractions (Fe, Mn, U, Mo, Ge, Cu, Ni, Co, V, and Cd) in a few cores suggest that anthigenic Ge removal in the suboxic zone is not associated with peaks in authigenic Mn cycling (MnO{sub 2} and related metals) but rather with processes deeper in the sediments, perhaps Fe or U diagenesis. Below the interval of Ge removal, pre water Ge increases linearly with depth by over two orders of magnitude, indicating a deep (below recovery) source of large magnitude. The fraction of opal-derived Ge precipitated authigenically in these sediments ranges from {approximately}1 to 96% and correlates strongly with the detrital fraction as well as the detrital to opal ratio, both of which generally decrease from north to south. The Ge sink observed in these sediments would need to be globally representative to account for the entire missing Ge sink in today's oceanic Ge balance, which seems unlikely. Benthic fluxes of Ge and Si estimated from these pore water profiles and from measurements in three benthic flux chamber experiments at high carbon-rain continental margin sites demonstrate that the Ge/Si rate released from the seafloor in locations with high benthic silicate and carbon fluxes is congruent with Holocene opal dissolution (Ge/Si {approximately} 0.7 x 10{sup {minus}6}). In contrast, Ge/Si flux ratios in areas with low silicate fluxes are Ge-depleted (Ge/Si < 0.5 x 10{sup {minus}6}). The authors speculate that glacial-interglacial changes in oceanic Ge/Si as recorded in diatoms may be due in part to variations in this authigenic Ge sink, perhaps related to shifts in siliceous productivity from open ocean (Antarctic) siliceous oozes during interglacials to areas of higher detrital input (Sub Antarctic, continental margins) and possibly also to generally more reducing conditions in sediments during glacials.

  2. Wave-function engineering and absorption spectra in Si{sub 0.16}Ge{sub 0.84}/Ge{sub 0.94}Sn{sub 0.06}/Si{sub 0.16}Ge{sub 0.84} strained on relaxed Si{sub 0.10}Ge{sub 0.90} type I quantum well

    SciTech Connect (OSTI)

    Yahyaoui, N., E-mail: naima.yahyaoui@yahoo.fr, E-mail: moncef-said@yahoo.fr; Sfina, N.; Said, M., E-mail: naima.yahyaoui@yahoo.fr, E-mail: moncef-said@yahoo.fr [Laboratoire de la Matière Condensée et des Nanosciences (LMCN), Département de Physique, Faculté des Sciences de Monastir, Avenue de l'Environnement, 5019 Monastir (Tunisia); Lazzari, J.-L. [Centre Interdisciplinaire de Nanoscience de Marseille (CINaM), UMR CNRS 7325, Aix-Marseille Université, Case 913, Campus de Luminy, 13288 Marseille cedex 9 (France); Bournel, A. [Institut d'Electronique Fondamentale (IEF), UMR CNRS 8622, Université Paris-Sud, Bât. 220, 91405 Orsay cedex (France)

    2014-01-21

    We theoretically investigate germanium-tin alloy as a semiconductor for the design of near infrared optical modulators in which the Ge{sub 1?x}Sn{sub x} alloy is the active region. We have calculated the electronic band parameters for heterointerfaces between strained Ge{sub 1?x}Sn{sub x} and relaxed Si{sub 1?y}Ge{sub y}. Then, a type-I strain-compensated Si{sub 0.10}Ge{sub 0.90}/Si{sub 0.16}Ge{sub 0.84}/Ge{sub 0.94}Sn{sub 0.06} quantum well heterostructure optimized in terms of compositions and thicknesses is studied by solving Schrödinger equation without and under applied bias voltage. The strong absorption coefficient (>1.5?×?10{sup 4}?cm{sup ?1}) and the shift of the direct transition under large Stark effect at 3?V are useful characteristics for the design of optoelectronic devices based on compressively strained IV-IV heterostructures at near infrared wavelengths.

  3. Low-energy enhancement in the \\gamma-ray strength functions of $^{73,74}$Ge

    E-Print Network [OSTI]

    Renstrøm, T; Utsumoniya, H; Schwengner, R; Goriely, S; Larsen, A C; Filipescu, D M; Gheorghe, I; Bernstein, L A; Bleuel, D L; Glodariu, T; Görgen, A; Guttormsen, M; Hagen, T W; Kheswa, B V; Lui, Y -W; Negi, D; Ruud, I E; Shima, T; Siem, S; Takahisa, K; Tesileanu, O; Tornyi, T G; Tveten, G M; Wiedeking, M

    2015-01-01

    The $\\gamma$-ray strength functions and level densities of $^{73,74}$Ge have been extracted up to the neutron separation energy S$_n$ from particle-$\\gamma$ coincidence data using the Oslo method. Moreover, the $\\gamma$-ray strength function of $^{74}$Ge above S$_n$ has been determined from photo-neutron measurements, hence these two experiments cover the range of E$_\\gamma \\approx$ 1-13 MeV for $^{74}$Ge. The obtained data show that both $^{73,74}$Ge display an increase in strength at low $\\gamma$ energies. The experimental $\\gamma$-ray strength functions are compared with $M1$ strength functions deduced from average $B(M1)$ values calculated within the shell model for a large number of transitions. The observed low-energy enhancements in $^{73,74}$Ge are adopted in the calculations of the $^{72,73}$Ge(n,$\\gamma$) cross sections, where there are no direct experimental data. Calculated reaction rates for more neutron-rich germanium isotopes are shown to be strongly dependent on the presence of the low-energy ...

  4. Low-energy enhancement in the ?-ray strength functions of $^{73,74}$Ge

    E-Print Network [OSTI]

    T. Renstrøm; H. -T. Nyhus; H. Utsumoniya; R. Schwengner; S. Goriely; A. C. Larsen; D. M. Filipescu; I. Gheorghe; L. A. Bernstein; D. L. Bleuel; T. Glodariu; A. Görgen; M. Guttormsen; T. W. Hagen; B. V. Kheswa; Y. -W . Lui; D. Negi; I. E. Ruud; T. Shima; S. Siem; K. Takahisa; O. Tesileanu; T. G. Tornyi; G. M. Tveten; M. Wiedeking

    2015-10-18

    The $\\gamma$-ray strength functions and level densities of $^{73,74}$Ge have been extracted up to the neutron separation energy S$_n$ from particle-$\\gamma$ coincidence data using the Oslo method. Moreover, the $\\gamma$-ray strength function of $^{74}$Ge above S$_n$ has been determined from photo-neutron measurements, hence these two experiments cover the range of E$_\\gamma \\approx$ 1-13 MeV for $^{74}$Ge. The obtained data show that both $^{73,74}$Ge display an increase in strength at low $\\gamma$ energies. The experimental $\\gamma$-ray strength functions are compared with $M1$ strength functions deduced from average $B(M1)$ values calculated within the shell model for a large number of transitions. The observed low-energy enhancements in $^{73,74}$Ge are adopted in the calculations of the $^{72,73}$Ge(n,$\\gamma$) cross sections, where there are no direct experimental data. Calculated reaction rates for more neutron-rich germanium isotopes are shown to be strongly dependent on the presence of the low-energy enhancement.

  5. Microstructure study of the rare-earth intermetallic compounds R5(SixGe1-x)4 and R5(SixGe1-x)3

    SciTech Connect (OSTI)

    Cao, Qing

    2012-07-26

    The unique combination of magnetic properties and structural transitions exhibited by many members of the R{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} family (R = rare earths, 0 ? x ? 1) presents numerous opportunities for these materials in advanced energy transformation applications. Past research has proven that the crystal structure and magnetic ordering of the R{sub 5(Si{sub x}Ge{sub 1-x}){sub 4} compounds can be altered by temperature, magnetic field, pressure and the Si/Ge ratio. Results of this thesis study on the crystal structure of the Er{sub 5}Si{sub 4} compound have for the first time shown that the application of mechanical forces (i.e. shear stress introduced during the mechanical grinding) can also result in a structural transition from Gd{sub 5}Si{sub 4}-type orthorhombic to Gd{sub 5}Si{sub 2}Ge{sub 2}-type monoclinic. This structural transition is reversible, moving in the opposite direction when the material is subjected to low-temperature annealing at 500 ?C. Successful future utilization of the R{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} family in novel devices depends on a fundamental understanding of the structure-property interplay on the nanoscale level, which makes a complete understanding of the microstructure of this family especially important. Past scanning electron microscopy (SEM) observation has shown that nanometer-thin plates exist in every R{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} (“5:4”) phase studied, independent of initial parent crystal structure and composition. A comprehensive electron microscopy study including SEM, energy dispersive spectroscopy (EDS), selected area diffraction (SAD), and high resolution transmission electron microscopy (HRTEM) of a selected complex 5:4 compound based on Er rather than Gd, (Er{sub 0.9Lu{sub 0.1}){sub 5}Si{sub 4}, has produced data supporting the assumption that all the platelet-like features present in the R{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} family are hexagonal R{sub 5}(Si{sub x}Ge{sub 1-x}){sub 3} (“5:3”) phase and possess the same reported orientation relationship that exists for the Gd{sub 5}Ge{sub 4} and Gd{sub 5}Si{sub 2}Ge{sub 2} compounds, i.e. [010](102?){sub m} || [101?0](12?11){sub p}. Additionally, the phase identification in (Er{sub 0.9}Lu{sub 0.1}){sub 5}Si{sub 4} carried out using X-ray powder diffraction (XRD) techniques revealed that the low amount of 5:3 phase is undetectable in a conventional laboratory Cu K? diffractometer due to detection limitations, but that extremely low amounts of the 5:3 phase can be detected using high resolution powder diffraction (HRPD) employing a synchrotron source. These results suggest that use of synchrotron radiation for the study of R{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} compounds should be favored over conventional XRD for future investigations. The phase stability of the thin 5:3 plates in a Gd{sub 5}Ge{sub 4} sample was examined by performing long-term annealing at very high temperature. The experimental results indicate the plates are thermally unstable above 1200?C. While phase transformation of 5:3 to 5:4 occurs during the annealing, the phase transition is still fairly sluggish, being incomplete even after 24 hours annealing at this elevated temperature. Additional experiments using laser surface melting performed on the surface of a Ho{sub 5}(Si{sub 0.8}Ge{sub 0.}2){sub 4} sample showed that rapid cooling will suppress the precipitation of 5:3 plates. Bulk microstructure studies of polycrystalline and monocrystalline Gd{sub 5}Ge{sub 3} compounds examined using optical microscopy, SEM and TEM also show a series of linear features present in the Gd{sub 5}Ge{sub 3} matrix, similar in appearance in many ways to the 5:3 plates observed in R{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} compounds. A systematic microscopy analysis of these linear features revealed they also are thin plates with a stoichiometric composition of Gd{sub 5}Ge{sub 4} with an orthorhombic structure. The orientation relationship between the 5:3 matrix and the precipitate 5:4 thin plates was determined as [101?0] (12?11){s

  6. Production and Testing Experience with the SRF Cavities for the CEBAF 12 GeV Upgrade

    SciTech Connect (OSTI)

    A. Burrill, G.K. Davis, F. Marhauser, C.E. Reece, A.V. Reilly, M. Stirbet

    2011-09-01

    The CEBAF recirculating CW electron linear accelerator at Jefferson Lab is presently undergoing a major upgrade to 12 GeV. This project includes the fabrication, preparation, and testing of 80 new 7-cell SRF cavities, followed by their incorporation into ten new cryomodules for subsequent testing and installation. In order to maximize the cavity Q over the full operable dynamic range in CEBAF (as high as 25 MV/m), the decision was taken to apply a streamlined preparation process that includes a final light temperature-controlled electropolish of the rf surface over the vendor-provided bulk BCP etch. Cavity processing work began at JLab in September 2010 and will continue through December 2011. The excellent performance results are exceeding project requirements and indicate a fabrication and preparation process that is stable and well controlled. The cavity production and performance experience to date will be summarized and lessons learned reported to the community.

  7. Dissociative Chemisorption of Methanol on Ge(100) Sung-Soo Bae, Do Hwan Kim,, Ansoon Kim,, Soon Jung Jung, Suklyun Hong,*, and

    E-Print Network [OSTI]

    Kim, Sehun

    Dissociative Chemisorption of Methanol on Ge(100) Sung-Soo Bae, Do Hwan Kim,, Ansoon Kim,,§ Soon of methanol (CH3OH) on Ge(100) surface has been studied using ultrahigh vacuum scanning tunneling microscopy-resolution experimental STM shows that methanol undergoes O-H bond dissociative adsorption on a single Ge-Ge dimer

  8. Liquid-metal-mediated homoepitaxial film growth of Ge at low temperature Fulin Xiong,a) Eric Ganz, A. G. Loeser, J. A. Golovchenko, and Frans Spaepen

    E-Print Network [OSTI]

    Golovchenko, Jene A.

    Liquid-metal-mediated homoepitaxial film growth of Ge at low temperature Fulin Xiong,a) Eric Ganz for publication 10 October 1991) We demonstrate liquid-metal-mediated homoepitaxial crystal growth of Ge on Ge. The liquid-metal phase at the interface is a Au-Ge alloy formed by initial deposition of a thin Au layer

  9. Multi-GeV neutrinos due to neutro anti-neutron oscillation in Gamma-Ray Burst Fireballs

    E-Print Network [OSTI]

    Sarira Sahu

    2007-02-27

    The long and short gamma-ray bursts are believed to be produced due to collapse of massive stars and merger of compact binaries respectively. All these objects are rich in neutron and the jet outflow from these objects must have a neutron component in it. By postulating the neutron anti-neutron oscillation in the gamma-ray burst fireball, we show that, 19-38 GeV neutrinos and anti-neutrinos can be produced due to annihilation of anti-neutrons with the background neutrons. These neutrinos and anti-neutrinos will be produced before the 5-10 GeV neutrinos due to dynamical decoupling of neutrons from the rest of the fireball. Observation of these neutrinos will shed more light on the nature of the GRB progenitors and also be a unique signature of physics beyond the standard model. A possible way of detecting these neutrinos in future is also discussed.

  10. K[superscript *0] production in Cu + Cu and Au + Au collisions at ?s[subscript NN]=62.4 GeV and 200 GeV

    E-Print Network [OSTI]

    Balewski, Jan T.

    We report on K[superscript *0] production at midrapidity in Au + Au and Cu + Cu collisions at ?s[subscript NN]=62.4 and 200 GeV collected by the Solenoid Tracker at the Relativistic Heavy Ion Collider detector. The ...

  11. K*0 production in Cu+Cu and Au+Au collisions at \\sqrt{s_NN} = 62.4 GeV and 200 GeV

    E-Print Network [OSTI]

    M. M. Aggarwal; Z. Ahammed; A. V. Alakhverdyants; I. Alekseev; J. Alford; B. D. Anderson; Daniel Anson; D. Arkhipkin; G. S. Averichev; J. Balewski; L. S. Barnby; S. Baumgart; D. R. Beavis; R. Bellwied; M. J. Betancourt; R. R. Betts; A. Bhasin; A. K. Bhati; H. Bichsel; J. Bielcik; J. Bielcikova; B. Biritz; L. C. Bland; B. E. Bonner; W. Borowski; J. Bouchet; E. Braidot; A. V. Brandin; A. Bridgeman; E. Bruna; S. Bueltmann; I. Bunzarov; T. P. Burton; X. Z. Cai; H. Caines; M. Calderon; O. Catu; D. Cebra; R. Cendejas; M. C. Cervantes; Z. Chajecki; P. chaloupka; S. Chattopadhyay; H. F. Chen; J. H. Chen; J. Y. Chen; J. Cheng; M. Cherney; A. Chikanian; K. E. Choi; W. Christie; P. Chung; R. F. Clarke; M. J. M. Codrington; R. Corliss; J. G. Cramer; H. J. Crawford; D. Das; S. Dash; A. Davila Leyva; L. C. De Silva; R. R. Debbe; T. G. Dedovich; A. A. Derevschikov; R. Derradi de Souza; L. Didenko; P. Djawotho; S. M. Dogra; X. Dong; J. L. Drachenberg; J. E. Draper; J. C. Dunlop; M. R. Dutta Mazumdar; L. G. Efimov; E. Elhalhuli; M. Elnimr; J. Engelage; G. Eppley; B. Erazmus; M. Estienne; L. Eun; O. Evdokimov; P. Fachini; R. Fatemi; J. Fedorisin; R. G. Fersch; P. Filip; E. Finch; V. Fine; Y. Fisyak; C. A. Gagliardi; D. R. Gangadharan; M. S. Ganti; E. J. Garcia-Solis; A. Geromitsos; F. Geurts; V. Ghazikhanian; P. Ghosh; Y. N. Gorbunov; A. Gordon; O. Grebenyuk; D. Grosnick; S. M. Guertin; A. Gupta; W. Guryn; B. Haag; A. Hamed; L-X. Han; J. W. Harris; J. P. Hays-Wehle; M. Heinz; S. Heppelmann; A. Hirsch; E. Hjort; A. M. Hoffman; G. W. Hoffmann; D. J. Hofman; B. Huang; H. Z. Huang; T. J. Humanic; L. Huo; G. Igo; P. Jacobs; W. W. Jacobs; C. Jena; F. Jin; C. L. Jones; P. G. Jones; J. Joseph; E. G. Judd; S. Kabana; K. Kajimoto; K. Kang; J. Kapitan; K. Kauder; D. Keane; A. Kechechyan; D. Kettler; D. P. Kikola; J. Kiryluk; A. Kisiel; V. Kizka; S. R. Klein; A. G. Knospe; A. Kocoloski; D. D. Koetke; T. Kollegger; J. Konzer; I. Koralt; L. Koroleva; W. Korsch; L. Kotchenda; V. Kouchpil; P. Kravtsov; K. Krueger; M. Krus; L. Kumar; P. Kurnadi; M. A. C. Lamont; J. M. Landgraf; S. LaPointe; J. Lauret; A. Lebedev; R. Lednicky; C-H. Lee; J. H. Lee; W. Leight; M. J. LeVine; C. Li; L. Li; N. Li; W. Li; X. Li; X. Li; Y. Li; Z. M. Li; G. Lin; S. J. Lindenbaum; M. A. Lisa; F. Liu; H. Liu; J. Liu; T. Ljubicic; W. J. Llope; R. S. Longacre; W. A. Love; Y. Lu; E. V. Lukashov; X. Luo; G. L. Ma; Y. G. Ma; D. P. Mahapatra; R. Majka; O. I. Mall; L. K. Mangotra; R. Manweiler; S. Margetis; C. Markert; H. Masui; H. S. Matis; Yu. A. Matulenko; D. McDonald; T. S. McShane; A. Meschanin; R. Milner; N. G. Minaev; S. Mioduszewski; A. Mischke; M. K. Mitrovski; B. Mohanty; M. M. Mondal; B. Morozov; D. A. Morozov; M. G. Munhoz; B. K. Nandi; C. Nattrass; T. K. Nayak; J. M. Nelson; P. K. Netrakanti; M. J. Ng; L. V. Nogach; S. B. Nurushev; G. Odyniec; A. Ogawa; V. Okorokov; E. W. Oldag; D. Olson; M. Pachr; B. S. Page; S. K. Pal; Y. Pandit; Y. Panebratsev; T. Pawlak; T. Peitzmann; C. Perkins; W. Peryt; S. C. Phatak; P. Pile; M. Planinic; M. A. Ploskon; J. Pluta; D. Plyku; N. Poljak; A. M. Poskanzer; B. V. K. S. Potukuchi; C. B. Powell; D. Prindle; C. Pruneau; N. K. Pruthi; P. R. Pujahari; J. Putschke; H. Qiu; R. Raniwala; S. Raniwala; R. L. Ray; R. Redwine; R. Reed; H. G. Ritter; J. B. Roberts; O. V. Rogachevskiy; J. L. Romero; A. Rose; C. Roy; L. Ruan; R. Sahoo; S. Sakai; I. Sakrejda; T. Sakuma; S. Salur; J. Sandweiss; E. Sangaline; J. Schambach; R. P. Scharenberg; N. Schmitz; T. R. Schuster; J. Seele; J. Seger; I. Selyuzhenkov; P. Seyboth; E. Shahaliev; M. Shao; M. Sharma; S. S. Shi; E. P. Sichtermann; F. Simon; R. N. Singaraju; M. J. Skoby; N. Smirnov; P. Sorensen; J. Sowinski; H. M. Spinka; B. Srivastava; T. D. S. Stanislaus; D. Staszak; J. R. Stevens; R. Stock; M. Strikhanov; B. Stringfellow; A. A. P. Suaide; M. C. Suarez; N. L. Subba; M. Sumbera; X. M. Sun; Y. Sun; Z. Sun; B. Surrow; D. N. Svirida; T. J. M. Symons; A. Szanto de Toledo; J. Takahashi; A. H. Tang; Z. Tang; L. H. Tarini; T. Tarnowsky; D. Thein; J. H. Thomas; J. Tian; A. R. Timmins; S. Timoshenko; D. Tlusty; M. Tokarev; T. A. Trainor; V. N. Tram; S. Trentalange; R. E. Tribble; O. D. Tsai; J. Ulery; T. Ullrich; D. G. Underwood; G. Van Buren; M. van Leeuwen; G. van Nieuwenhuizen; J. A. Vanfossen, Jr.; R. Varma; G. M. S. Vasconcelos; A. N. Vasiliev; F. Videbaek; Y. P. Viyogi; S. Vokal; S. A. Voloshin; M. Wada; M. Walker; F. Wang; G. Wang; H. Wang; J. S. Wang; Q. Wang; X. L. Wang; Y. Wang; G. Webb; J. C. Webb; G. D. Westfall; C. Whitten Jr.; H. Wieman; S. W. Wissink; R. Witt; Y. F. Wu; W. Xie; H. Xu; N. Xu; Q. H. Xu; W. Xu; Y. Xu; Z. Xu; L. Xue; Y. Yang; P. Yepes; K. Yip; I-K. Yoo; Q. Yue; M. Zawisza; H. Zbroszczyk; W. Zhan; J. B. Zhang; S. Zhang; W. M. Zhang; X. P. Zhang; Y. Zhang; Z. P. Zhang; J. Zhao; C. Zhong; J. Zhou; W. Zhou; X. Zhu; Y. H. Zhu; R. Zoulkarneev

    2010-06-10

    We report on K*0 production at mid-rapidity in Au+Au and Cu+Cu collisions at \\sqrt{s_{NN}} = 62.4 and 200 GeV collected by the Solenoid Tracker at RHIC (STAR) detector. The K*0 is reconstructed via the hadronic decays K*0 \\to K+ pi- and \\bar{K*0} \\to K-pi+. Transverse momentum, pT, spectra are measured over a range of pT extending from 0.2 GeV/c to 5 GeV/c. The center of mass energy and system size dependence of the rapidity density, dN/dy, and the average transverse momentum, , are presented. The measured N(K*0)/N(K) and N(\\phi)/N(K*0) ratios favor the dominance of re-scattering of decay daughters of K*0 over the hadronic regeneration for the K*0 production. In the intermediate pT region (2.0 < pT < 4.0 GeV/c), the elliptic flow parameter, v2, and the nuclear modification factor, RCP, agree with the expectations from the quark coalescence model of particle production.

  12. Band alignment at interfaces of amorphous Al{sub 2}O{sub 3} with Ge{sub 1?x}Sn{sub x}- and strained Ge-based channels

    SciTech Connect (OSTI)

    Chou, H.-Y.; Afanas'ev, V. V., E-mail: valeri.afanasiev@fys.kuleuven.be; Houssa, M.; Stesmans, A. [Department of Physics, University of Leuven, Celestijnenlaan 200D, B-3001 Leuven (Belgium); Vincent, B.; Gencarelli, F.; Shimura, Y.; Merckling, C.; Loo, R. [Imec, Kapeldreef 75, B-3001 Leuven (Belgium); Nakatsuka, O.; Zaima, S. [Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan)

    2014-05-19

    Spectroscopy of internal photoemission of electrons from Ge and Ge{sub 1?x}Sn{sub x} (x???0.08) alloys into amorphous Al{sub 2}O{sub 3} is used to evaluate the energy of the semiconductor valence band top. It is found that in Ge and Ge{sub 1?x}Sn{sub x} the valence bands are aligned within the measurement accuracy (±0.05?eV) irrespective of the strain imposed on the semiconductor or by the kind of passivating inter-layer applied between the semiconductor and alumina. This indicates that the Ge{sub 1?x}Sn{sub x}-stressor approach may be useful for strain engineering in p-channel Ge metal-oxide-semiconductor transistors.

  13. Searches for exotic decays of the 125 GeV Higgs boson and the lightest neutral Higgs boson in NMSSM with the ATLAS detector

    E-Print Network [OSTI]

    Looper, Kristina Anne; The ATLAS collaboration

    2015-01-01

    We present the results of searches for non-Standard Model decays of the 125 GeV Higgs boson, including decays to dark sector bosons, lepton flavour violating and flavour changing decays, and decays to a light pseudoscalar neutral Higgs boson (a) predicted by the next-Minimal-Supersymmetric-Standard-Model.

  14. The First-cycle Electrochemical Lithiation of Crystalline Ge – Dopant and Orientation Dependence, and Comparison with Si

    SciTech Connect (OSTI)

    Chan, Maria K.Y.; Long, Brandon R.; Gewirth, Andrew A.; Greeley, Jeffrey P.

    2011-12-15

    We use first principles Density Functional Theory (DFT), cyclic voltammetry (CV), and Raman spectroscopy to investigate the first-cycle electrochemical lithiation of Ge in comparison with Si – both high-capacity anode materials for Li ion batteries. DFT shows a significant difference in the dilute solubility of Li in Si and Ge, despite similarities in their chemical and physical properties. We attribute this difference to electronic, as opposed to elastic, effects. CV and Raman data reveal little dopant dependence in the lithiation onset voltages in Ge, unlike in Si, due to a smaller energy difference between dilute Li insertion in p-type Ge and bulk germanide formation than the corresponding difference in Si. Finally, we show that there is no orientation dependence in lithiation onset voltages in Ge. We conclude that approaches other than microstructuring are needed to fabricate effective electrodes able to take advantage of the higher rate capability of Ge compared to that of Si.

  15. Electrical properties of diluted n- and p-Si{sub 1?x}Ge{sub x} at small x

    SciTech Connect (OSTI)

    Emtsev, V. V., E-mail: emtsev@mail.ioffe.ru [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation); Abrosimov, N. V. [Leibniz Institute for Crystal Growth (Germany); Kozlovskii, V. V. [St. Petersburg Polytechnical State University (Russian Federation); Oganesyan, G. A. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)

    2014-12-15

    Hall effect and conductivity measurements are taken on Si{sub 1?x}Ge{sub x} of n- and p-type at x ? 0.05. Much attention is given to electrical measurements over a temperature interval of 25 to 40 K where the mobility of charged carriers is strongly affected by alloy scattering. The partial mobility of electrons and holes due to this scattering mechanism is estimated for n-Si{sub 1?x}Ge{sub x} and p-Si{sub 1?x}Ge{sub x} at small x. Together with this, an effect of the presence of Ge atoms upon the ionization energy of phosphorus and boron impurities is investigated. Some points related to an inhomogeneous distribution of Ge atoms in Si{sub 1?x}Ge{sub x} are discussed.

  16. Structure and magnetism in strained Ge{sub 1-x-y}Sn{sub x}Mn{sub y} films grown on Ge(001) by low temperature molecular beam epitaxy

    SciTech Connect (OSTI)

    Prestat, E. [INAC, SP2M, CEA and Universite Joseph Fourier, 17 rue des Martyrs, 38054 Grenoble (France); Karlsruher Institut fuer Technologie (KIT), Laboratorium fuer Elektronenmikroskopie, D-76128 Karlsruhe (Germany); Barski, A.; Bellet-Amalric, E.; Morel, R.; Tainoff, D.; Jain, A.; Porret, C.; Bayle-Guillemaud, P.; Jamet, M. [INAC, SP2M, CEA and Universite Joseph Fourier, 17 rue des Martyrs, 38054 Grenoble (France); Jacquot, J.-F. [INAC, SCIB, CEA and Universite Joseph Fourier, 17 rue des Martyrs, 38054 Grenoble (France)

    2013-07-01

    In this letter, we study the structural and magnetic properties of Ge{sub 1-x-y}Sn{sub x}Mn{sub y} films grown on Ge(001) by low temperature molecular beam epitaxy using X-ray diffraction, high resolution transmission electron microscopy, and superconducting quantum interference device. Like in Mn doped Ge films, Mn atoms diffuse during the growth and aggregate into vertically aligned Mn-rich nanocolumns of a few nanometers in diameter. Transmission electron microscopy observations in plane view clearly indicate that the Sn incorporation is not uniform with concentration in Mn rich vertical nanocolumns lower than the detection limit of electron energy loss spectroscopy. The matrix exhibits a GeSn solid solution while there is a Sn-rich GeSn shell around GeMn nanocolumns. The magnetization in Ge{sub 1-x-y}Sn{sub x}Mn{sub y} layers is higher than in Ge{sub 1-x}Mn{sub x} films. This magnetic moment enhancement in Ge{sub 1-x-y}Sn{sub x}Mn{sub y} is probably related to the modification of the electronic structure of Mn atoms in the nanocolumns by the Sn-rich shell, which is formed around the nanocolumns.

  17. Centrality dependence of the thermal excitation-energy deposition in 8-15 GeV/c hadron-Au reactions

    E-Print Network [OSTI]

    R. A. Soltz; R. J. Newby; J. L. Klay; M. Heffner; L. Beaulieu; T. Lefort; K. Kwiatkowski; V. E. Viola

    2009-01-09

    The excitation energy per residue nucleon (E*/A) and fast and thermal light particle multiplicities are studied as a function of centrality defined as the number of grey tracks emitted N_grey and by the mean number of primary hadron-nucleon scatterings and mean impact parameter extracted from it. The value of E*/A and the multiplicities show an increase with centrality for all systems, 14.6 GeV p-Au and 8.0 GeV pi-Au and pbar-Au collisions, and the excitation energy per residue nucleon exhibits a uniform dependence on N_grey.

  18. The Majorana Demonstrator: Progress towards showing the feasibility of a 76Ge neutrinoless double-beta decay experiment

    SciTech Connect (OSTI)

    Finnerty, P.; Aguayo, Estanislao; Amman, M.; Avignone, Frank T.; Barabash, Alexander S.; Barton, P. J.; Beene, Jim; Bertrand, F.; Boswell, M.; Brudanin, V.; Busch, Matthew; Chan, Yuen-Dat; Christofferson, Cabot-Ann; Collar, J. I.; Combs, Dustin C.; Cooper, R. J.; Detwiler, Jason A.; Doe, P. J.; Efremenko, Yuri; Egorov, Viatcheslav; Ejiri, H.; Elliott, S. R.; Esterline, James H.; Fast, James E.; Fields, N.; Fraenkle, Florian; Galindo-Uribarri, A.; Gehman, Victor M.; Giovanetti, G. K.; Green, M.; Guiseppe, Vincente; Gusey, K.; Hallin, A. L.; Hazama, R.; Henning, Reyco; Hoppe, Eric W.; Horton, Mark; Howard, Stanley; Howe, M. A.; Johnson, R. A.; Keeter, K.; Kidd, M. F.; Knecht, A.; Kochetov, Oleg; Konovalov, S.; Kouzes, Richard T.; LaFerriere, Brian D.; Leon, Jonathan D.; Leviner, L.; Loach, J. C.; Looker, Q.; Luke, P.; MacMullin, S.; Marino, Michael G.; Martin, R. D.; Merriman, Jason H.; Miller, M. L.; Mizouni, Leila; Nomachi, Masaharu; Orrell, John L.; Overman, Nicole R.; Perumpilly, Gopakumar; Phillips, David; Poon, Alan; Radford, D. C.; Rielage, Keith; Robertson, R. G. H.; Ronquest, M. C.; Schubert, Alexis G.; Shima, T.; Shirchenko, M.; Snavely, Kyle J.; Steele, David; Strain, J.; Timkin, V.; Tornow, Werner; Varner, R. L.; Vetter, Kai; Vorren, Kris R.; Wilkerson, J. F.; Yakushev, E.; Yaver, Harold; Young, A.; Yu, Chang-Hong; Yumatov, Vladimir

    2014-03-24

    The Majorana Demonstrator will search for the neutrinoless double-beta decay (0*) of the 76Ge isotope with a mixed array of enriched and natural germanium detectors. The observation of this rare decay would indicate the neutrino is its own anti-particle, demonstrate that lepton number is not conserved, and provide information on the absolute mass-scale of the neutrino. The Demonstrator is being assembled at the 4850 foot level of the Sanford Underground Research Facility in Lead, South Dakota. The array will be contained in a lowbackground environment and surrounded by passive and active shielding. The goals for the Demonstrator are: demonstrating a background rate less than 3 counts tonne -1 year-1 in the 4 keV region of interest (ROI) surrounding the 2039 keV 76Ge endpoint energy; establishing the technology required to build a tonne-scale germanium based double-beta decay experiment; testing the recent claim of observation of 0; and performing a direct search for lightWIMPs (3-10 GeV/c2).

  19. Particle Production of Mercury Target with 15Tto2T5m Configuration at 6.75 GeV

    E-Print Network [OSTI]

    McDonald, Kirk

    Particle Production of Mercury Target with 15Tto2T5m Configuration at 6.75 GeV X. Ding, UCLA beam with waist at z= 0 m and emittance of 5 m; · Production Collection: (50 m downstream, 40 MeV : 0.0145 GeV); EPSTAM: The star production threshold kinetic energy (Default: 0.03 GeV); EMCHR

  20. Control of tensile strain and interdiffusion in Ge/Si(001) epilayers grown by molecular-beam epitaxy

    SciTech Connect (OSTI)

    Luong, T. K. P.; Dau, M. T.; Zrir, M. A.; Le Thanh, V.; Petit, M. [Aix-Marseille Université, CNRS CINaM-UMR 7325, F-13288 Marseille Cedex 09 (France)] [Aix-Marseille Université, CNRS CINaM-UMR 7325, F-13288 Marseille Cedex 09 (France); Stoffel, M.; Rinnert, H. [Université de Lorraine, Institut Jean Lamour, CNRS UMR 7198, Nancy-Université, BP 70239, 54506 Vandoeuvre-lès-Nancy Cedex (France)] [Université de Lorraine, Institut Jean Lamour, CNRS UMR 7198, Nancy-Université, BP 70239, 54506 Vandoeuvre-lès-Nancy Cedex (France); Ghrib, A.; El Kurdi, M.; Boucaud, P. [Institut d'Electronique Fondamentale, CNRS UMR 8622, Université Paris-Sud, Ba-carett. 220, 91405 Orsay (France)] [Institut d'Electronique Fondamentale, CNRS UMR 8622, Université Paris-Sud, Ba-carett. 220, 91405 Orsay (France); Murota, J. [Research Institute of Electrical Communications, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)] [Research Institute of Electrical Communications, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)

    2013-08-28

    Tensile-strained and n-doped Ge has emerged as a potential candidate for the realization of optoelectronic devices that are compatible with the mainstream silicon technology. Tensile-strained Ge/Si epilayers can be obtained by using the difference of thermal expansion coefficients between Ge and Si. We have combined various surface, structural, and compositional characterizations to investigate the growth mode and the strain state in Ge/Si epilayers grown by molecular-beam epitaxy. The Ge growth was carried out using a two-step approach: a low-temperature growth to produce relaxed and smooth buffer layers, which is followed by a high-temperature growth to get high quality Ge layers. The existence of a substrate temperature window from 260 to 300 °C is evidenced, which allows to completely suppress the Ge/Si Stranski-Krastanov growth. As a consequence of the high temperature growth, a tensile strain lying in the range of 0.22%–0.24% is obtained. Concerning the effect of thermal annealing, it is shown that cyclic annealing may allow increasing the tensile strain up to 0.30%. Finally, we propose an approach to use carbon adsorption to suppress Si/Ge interdiffusion, which represents one of the main obstacles to overcome in order to realize pure Ge-based optoelectronic devices.

  1. FERMI-LAT DETECTION OF PULSED GAMMA-RAYS ABOVE 50 GeV FROM THE VELA PULSAR

    SciTech Connect (OSTI)

    Leung, Gene C. K.; Takata, J.; Ng, C. W.; Cheng, K. S. [Department of Physics, The University of Hong Kong, Pokfulam Road (Hong Kong); Kong, A. K. H.; Tam, P. H. T. [Institute of Astronomy and Department of Physics, National Tsing Hua University, Hsinchu, Taiwan (China); Hui, C. Y., E-mail: gene930@connect.hku.hk, E-mail: takata@hku.hk [Department of Astronomy and Space Science, Chungnam National University, Daejeon (Korea, Republic of)

    2014-12-20

    The first Fermi-Large Area Telescope (LAT) catalog of sources above 10 GeV reported evidence of pulsed emission above 25 GeV from 12 pulsars, including the Vela pulsar, which showed evidence of pulsation at >37 GeV energy bands. Using 62 months of Fermi-LAT data, we analyzed the gamma-ray emission from the Vela pulsar and searched for pulsed emission above 50 GeV. Having confirmed the significance of the pulsation in 30-50 GeV with the H test (p-value ?10{sup –77}), we extracted its pulse profile using the Bayesian block algorithm and compared it with the distribution of the five observed photons above 50 GeV using the likelihood ratio test. Pulsation was significantly detected for photons above 50 GeV with a p-value of =3 × 10{sup –5} (4.2?). The detection of pulsation is significant above 4? at >79 GeV and above 3? at >90 GeV energy bands, making this the highest energy pulsation significantly detected by the LAT. We explore the non-stationary outer gap scenario of the very high-energy emissions from the Vela pulsar.

  2. Si/SiGe electron resonant tunneling diodes with graded spacer wells

    SciTech Connect (OSTI)

    Paul, D. J.; See, P.; Bates, R.; Griffin, N.; Coonan, B. P.; Redmond, G.; Crean, G. M.; Zozoulenko, I. V.; Berggren, K.-F.; Hollander, B.

    2001-06-25

    Resonant tunneling diodes have been fabricated using graded Si{sub 1{minus}x}Ge{sub x} (x=0.3{r_arrow}0.0) spacer wells and strained Si{sub 0.4}Ge{sub 0.6} barriers on a relaxed Si{sub 0.7}Ge{sub 0.3} n-type substrate which demonstrates negative differential resistance at up to 100 K. This design is aimed at reducing the voltage at which the peak current density is achieved. Peak current densities of 0.08A/cm{sup 2} with peak-to-valley current ratios of 1.67 have been achieved for a low peak voltage of 40 mV at 77 K. This represents an improvement of over an order of magnitude compared to previous work. {copyright} 2001 American Institute of Physics.

  3. Characterization of neutron transmutation doped (NTD) Ge for low temperature sensor development

    E-Print Network [OSTI]

    S. Mathimalar; V. Singh; N. Dokania; V. Nanal; R. G. Pillay; S. Pal; S. Ramakrishnan; A. Shrivastava; Priya Maheshwari; P. K. Pujari; S. Ojha; D. Kanjilal; K. C. Jagadeesan; S. V. Thakare

    2014-12-05

    Development of NTD Ge sensors has been initiated for low temperature (mK) thermometry in The India-based Tin detector (TIN.TIN). NTD Ge sensors are prepared by thermal neutron irradiation of device grade Ge samples at Dhruva reactor, BARC, Mumbai. Detailed measurements have been carried out in irradiated samples for estimating the carrier concentration and fast neutron induced defects. The Positron Annihilation Lifetime Spectroscopy (PALS) measurements indicated monovacancy type defects for all irradiated samples, while Channeling studies employing RBS with 2 MeV alpha particles, revealed no significant defects in the samples exposed to fast neutron fluence of $\\sim 4\\times10^{16}/cm^2$. Both PALS and Channeling studies have shown that vacuum annealing at 600 $^\\circ$C for $\\sim2$ hours is sufficient to recover the damage in the irradiated samples, thereby making them suitable for the sensor development.

  4. Pd-vacancy complex in Ge: TDPAC and ab initio study

    SciTech Connect (OSTI)

    Abiona, Adurafimihan A.; Kemp, Williams; Timmers, Heiko [School of Physical, Environmental and Mathematical Sciences, The University of New South Wales, UNSW Canberra, PO Box 7916, Canberra BC 2610 (Australia)

    2014-02-21

    Low temperature metal-induced-crystallized germanium is a promising alternative for silicon in Complementary Metal-Oxide-Semiconductor (CMOS) technology. Palladium (Pd) is one of the metals suitable for inducing the low temperature crystallization. It is not certain, how residual Pd atoms are integrated into the Ge lattice. Therefore, time-different ?-? perturbed angular correlation (TDPAC) technique using the {sup 100}Pd(?{sup 100}Rh) nuclear probe has been applied to study the hyperfine interactions of this probe in single crystalline undoped Ge. A Pd-vacancy (Pd-V) complex with a unique interaction frequency of 8.4(2) Mrad/s has been identified. The Pd-V complex has been measured to have a maximum fraction after annealing at 350 °C. Density functional theory calculations have confirmed that the Pd-V complex may have the split-vacancy configuration in Ge, in contrast to the full-vacancy configuration observed in Si.

  5. Electronic structural and magnetic properties of Mn{sub 5}Ge{sub 3} clusters

    SciTech Connect (OSTI)

    Yuan, H. K.; Chen, H. Kuang, A. L.; Tian, C. L.; Wang, J. Z.

    2013-11-28

    Theoretical understanding of the stability, ferromagnetism, and spin polarization of Mn{sub 5}Ge{sub 3} clusters has been performed by using the density functional theory with generalized gradient approximation for exchange and correlation. The magnetic moments and magnetic anisotropy energy (MAE) have been calculated for both bulk and clusters, and the enhanced magnetic moment as well as the enlarged MAE have been identified in clusters. The most attractive achievement is that Mn{sub 5}Ge{sub 3} clusters show a fine half-metallic character with large energy scales. The present results may have important implications for potential applications of small Mn{sub 5}Ge{sub 3} clusters as both emerging spintronics and next-generation data-storage technologies.

  6. Highly bent (110) Ge crystals for efficient steering of ultrarelativistic beams

    SciTech Connect (OSTI)

    De Salvador, D.; Maggioni, G.; Carturan, S.; Bazzan, M.; Argiolas, N.; Carnera, A.; Dalla Palma, M.; Della Mea, G.; Bagli, E.; Mazzolari, A.; Bandiera, L.; Guidi, V.; Lietti, D.; Berra, A.; Guffanti, G.; Prest, M.; Vallazza, E.

    2013-10-21

    Thanks to the effective electrostatic potential generated by the ordered atomic structure, bent crystals can efficiently deflect ultra relativistic charged beams by means of planar and axial channeling phenomena as well as of the recently discovered volume reflection effect. Most of the experimental knowledge about these phenomena has been gathered with Si crystals, but it has been recently demonstrated that the steering performance can be improved by using high quality Ge materials which have a larger atomic number. In this paper, we investigate channeling and volume reflection of 400 GeV protons from (110) lattice planes in highly bent Ge strips crystals. Both production and characterization of the strips are presented. Herein, the experimental results on deflection are compared with theoretical predictions, with previous published data and with the expected performances of Si crystals in similar experimental conditions.

  7. First results on Cosmic Ray electron spectrum below 20 GeV from the Fermi LAT

    E-Print Network [OSTI]

    Pesce-Rollins, Melissa

    2009-01-01

    Designed to be a successor of the previous flown space based gamma ray detectors, the Fermi Large Area Telescope (LAT) is also an electron detector. Taking advantage of its capability to separate electromagnetic and hadronic signals it is possible to accurately measure the Cosmic Ray electron spectrum. The spectra of primary cosmic ray electrons below 20 GeV is influenced by many local effects such as solar modulation and the geomagnetic cutoff. For energies below a few GeV it is possible to observe the albedo population of electrons which are controlled by the local magnetic field. In this paper we present the LAT electron analysis in particular event selection and validation as well as the first results on the measurement of the electron spectrum below 20 GeV.

  8. 5-10 GeV Neutrinos from Gamma-Ray Burst Fireballs

    E-Print Network [OSTI]

    John N. Bahcall; Peter Meszaros

    2000-06-23

    A gamma-ray burst fireball is likely to contain an admixture of neutrons, in addition to protons, in essentially all progenitor scenarios. Inelastic collisions between differentially streaming protons and neutrons in the fireball produce muon neutrinos (antineutrinos) of ~ 10 GeV as well as electron neutrinos (antineutrinos) of ~ 5 GeV, which could produce ~ 7 events/year in kilometer cube detectors, if the neutron abundance is comparable to that of protons. Photons of ~ 10 GeV from pi-zero decay and ~ 100 MeV electron antineutrinos from neutron decay are also produced, but will be difficult to detect. Photons with energies < 1 MeV from shocks following neutron decay produce a characteristic signal which may be distinguishable from the proton-related MeV photons.

  9. MaGe - a Geant4-based Monte Carlo framework for low-background experiments

    E-Print Network [OSTI]

    Yuen-Dat Chan; Jason A. Detwiler; Reyco Henning; Victor M. Gehman; Rob A. Johnson; David V. Jordan; Kareem Kazkaz; Markus Knapp; Kevin Kroninger; Daniel Lenz; Jing Liu; Xiang Liu; Michael G. Marino; Akbar Mokhtarani; Luciano Pandola; Alexis G. Schubert; Claudia Tomei

    2008-02-06

    A Monte Carlo framework, MaGe, has been developed based on the Geant4 simulation toolkit. Its purpose is to simulate physics processes in low-energy and low-background radiation detectors, specifically for the Majorana and Gerda $^{76}$Ge neutrinoless double-beta decay experiments. This jointly-developed tool is also used to verify the simulation of physics processes relevant to other low-background experiments in Geant4. The MaGe framework contains simulations of prototype experiments and test stands, and is easily extended to incorporate new geometries and configurations while still using the same verified physics processes, tunings, and code framework. This reduces duplication of efforts and improves the robustness of and confidence in the simulation output.

  10. The JLAB 3D program at 12 GeV (TMDs + GPDs)

    SciTech Connect (OSTI)

    Pisano, Silvia [Lab. Naz. Frascati, Frascati, Italy

    2015-01-01

    The Jefferson Lab CEBAF accelerator is undergoing an upgrade that will increase the beam energy up to 12 GeV. The three experimental Halls operating in the 6-GeV era are upgrading their detectors to adapt their performances to the new available kinematics, and a new Hall (D) is being built. The investigation of the three-dimensional nucleon structure both in the coordinate and in the momentum space represents an essential part of the 12-GeV physics program, and several proposals aiming at the extraction of related observables have been already approved in Hall A, B and C. In this proceedings, the focus of the JLab 3D program will be described, and a selection of proposals will be discussed.

  11. An aerogel Cherenkov detector for multi-GeV photon detection with low sensitivity to neutrons

    E-Print Network [OSTI]

    Maeda, Y; Masuda, T; Morii, H; Naito, D; Nakajima, Y; Nanjo, H; Nomura, T; Sasao, N; Seki, S; Shiomi, K; Sumida, T; Tajima, Y

    2014-01-01

    We describe a novel photon detector which operates under an intense flux of neutrons. It is composed of lead-aerogel sandwich counter modules. Its salient features are high photon detection efficiency and blindness to neutrons. As a result of Monte Carlo (MC) simulations, the efficiency for photons with the energy larger than 1 GeV is expected to be higher than 99.5% and that for 2 GeV/$c$ neutrons less than 1%. The performance on the photon detection under such a large flux of neutrons was measured for a part of the detector. It was confirmed that the efficiency to photons with the energy $>$1 GeV was consistent with the MC expectation within 8.2% uncertainty.

  12. An aerogel Cherenkov detector for multi-GeV photon detection with low sensitivity to neutrons

    E-Print Network [OSTI]

    Y. Maeda; N. Kawasaki; T. Masuda; H. Morii; D. Naito; Y. Nakajima; H. Nanjo; T. Nomura; N. Sasao; S. Seki; K. Shiomi; T. Sumida; Y. Tajima

    2014-12-22

    We describe a novel photon detector which operates under an intense flux of neutrons. It is composed of lead-aerogel sandwich counter modules. Its salient features are high photon detection efficiency and blindness to neutrons. As a result of Monte Carlo (MC) simulations, the efficiency for photons with the energy larger than 1 GeV is expected to be higher than 99.5% and that for 2 GeV/$c$ neutrons less than 1%. The performance on the photon detection under such a large flux of neutrons was measured for a part of the detector. It was confirmed that the efficiency to photons with the energy $>$1 GeV was consistent with the MC expectation within 8.2% uncertainty.

  13. ? meson production in d+Au collisions at ?sNN = 200 GeV

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

    Adare, A.

    2015-10-19

    The PHENIX Collaboration has measured ? meson production in d+Au collisions at ?sNN=200 GeV using the dimuon and dielectron decay channels. The ? meson is measured in the forward (backward) d-going (Au-going) direction, 1.2 T) range from 1–7 GeV/c and at midrapidity |y|T range below 7 GeV/c. The ? meson invariant yields and nuclear-modification factors as a function of pT, rapidity, and centrality are reported. An enhancement of ? meson production is observed in the Au-going direction, while suppression is seen in the d-going direction,more »and no modification is observed at midrapidity relative to the yield in p+p collisions scaled by the number of binary collisions. As a result, similar behavior was previously observed for inclusive charged hadrons and open heavy flavor, indicating similar cold-nuclear-matter effects.« less

  14. Search for neutrinoless double-beta decay of Ge-76 with GERDA

    E-Print Network [OSTI]

    Karl-Tasso Knoepfle

    2008-10-17

    GERDA, the GERmanium Detector Array experiment, is a new double beta-decay experiment which is currently under construction in the INFN National Gran Sasso Laboratory (LNGS), Italy. It is implementing a new shielding concept by operating bare Ge diodes - enriched in Ge-76 - in high purity liquid argon supplemented by a water shield. The aim of GERDA is to verify or refute the recent claim of discovery, and, in a second phase, to achieve a two orders of magnitude lower background index than recent experiments. The paper discusses motivation, physics reach, design and status of construction of GERDA, and presents some R&D results.

  15. Measurements of spin parameters in p-p elastic scattering at 6 GeV/c

    SciTech Connect (OSTI)

    Linn, S.L.; Perlmutter, A.; Crosbie, E.A.; Ratner, L.G.; Schultz, P.F.; O'Fallon, J.R.; Cameron, P.R.; Crabb, D.G.; Fernow, R.C.; Hansen, P.H.; Krisch, A.D.; Salthouse, A.J.; Sandler, B.; Shima, T.; Terwilliger, K.M.

    1982-08-01

    We measured the differential cross section for proton-proton elastic scattering in 6 GeV/c, with both initial spins oriented normal to the scattering plane. The analyzing power A shows significant structure with a large broad peak reaching about 24% near P/sub perpendicular/ /sup 2/ = 1.6 (GeV/c)/sup 2/. The spin-spin correlation parameter A/sub n/n exhibits more dramatic structure, with a small but very sharp peak rising rapidly to about 13% at 90/sup 0//sub tsc.m./. This sharp peak may be caused by particle-identity effects.

  16. Higgs portal, fermionic dark matter, and a Standard Model like Higgs at 125 GeV

    E-Print Network [OSTI]

    Laura Lopez-Honorez; Thomas Schwetz; Jure Zupan

    2012-07-09

    We show that fermionic dark matter (DM) which communicates with the Standard Model (SM) via the Higgs portal is a viable scenario, even if a SM-like Higgs is found at around 125 GeV. Using effective field theory we show that for DM with a mass in the range from about 60 GeV to 2 TeV the Higgs portal needs to be parity violating in order to be in agreement with direct detection searches. For parity conserving interactions we identify two distinct options that remain viable: a resonant Higgs portal, and an indirect Higgs portal. We illustrate both possibilities using a simple renormalizable toy model.

  17. Straw man 900-1000 GeV crystal extraction test beam for Fermilab collider operation

    SciTech Connect (OSTI)

    Carrigan, R.A. Jr.

    1996-10-01

    A design for a 900-1000 GeV, 100 khz parasitic test beam for use during collider operations has been developed. The beam makes use of two bent crystals, one for extraction and the other one for redirecting the beam in to the present Switchyard beam system. The beam requires only a few modifications in the A0 area and largely uses existing devices. It should be straight-forward to modify one or two beam lines in the fixed target experimental areas to work above 800 GeV. Possibilities for improvements to the design,to operate at higher fluxes are discussed.

  18. 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.

  19. Electrical characteristics of Ni Ohmic contact on n-type GeSn

    SciTech Connect (OSTI)

    Li, H.; Cheng, H. H., E-mail: hhcheng@ntu.edu.tw [Center for Condensed Matter Sciences and Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 106, Taiwan (China); Lee, L. C.; Lee, C. P. [Center for Nano Science and Technology, National Chiao Tung University, Hsinchu 300, Taiwan (China); Su, L. H.; Suen, Y. W. [Department of Physics and Institute of Nano Science, National Chung Hsing University, Taichung 402, Taiwan (China)

    2014-06-16

    We report an investigation of the electrical and material characteristics of Ni on an n-type GeSn film under thermal annealing. The current-voltage traces measured with the transmission line method are linear for a wide range of annealing temperatures. The specific contact resistivity was found to decrease with increasing annealing temperature, followed by an increase as the annealing temperature further increased, with a minimum value at an annealing temperature of 350?°C. The material characteristics at the interface layer were measured by energy-dispersive spectrometer, showing that an atomic ratio of (Ni)/(GeSn)?=?1:1 yields the lowest specific contact resistivity.

  20. Dislocation engineering in SiGe heteroepitaxial films on patterned Si (001) substrates

    SciTech Connect (OSTI)

    Gatti, R.; Boioli, F.; Montalenti, F.; Miglio, Leo [L-NESS and Dipartimento di Scienza dei Materiali, Universita degli Studi di Milano-Bicocca, via R. Cozzi 53, I-20125 Milano (Italy); Grydlik, M.; Brehm, M.; Groiss, H.; Glaser, M.; Fromherz, T.; Schaeffler, F. [Institut fuer Halbleiter- und Festkoerperphysik, Johannes Kepler Universitaet, Altenberger Str. 69, A-4040 Linz (Austria)

    2011-03-21

    We demonstrate dislocation engineering without oxide masks. By using finite element simulations we show how nanopatterning of Si substrates with (111) trenches provides anisotropic elastic relaxation in a SiGe film, generates preferential nucleation sites for dislocation loops, and allows for dislocation trapping, leaving wide areas free of threading dislocations. These predictions are confirmed by atomic force and transmission electron microscopy performed on overcritical Si{sub 0.7}Ge{sub 0.3} films. These were grown by molecular beam epitaxy on a Si(001) substrate patterned with periodic arrays of selectively etched (111)-terminated trenches.

  1. Misfit dislocation gettering by substrate pit-patterning in SiGe films on Si(001)

    SciTech Connect (OSTI)

    Grydlik, Martyna; Groiss, Heiko; Brehm, Moritz; Schaeffler, Friedrich [Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz, Altenbergerstrasse 69, A-4040 Linz (Austria); Boioli, Francesca; Montalenti, Francesco; Miglio, Leo [L-NESS and Department of Material Science, University of Milano-Bicocca (Italy); Gatti, Riccardo; Devincre, Benoit [LEM, CNRS/ONERA, Chatillon Cedex (France)

    2012-07-02

    We show that suitable pit-patterning of a Si(001) substrate can strongly influence the nucleation and the propagation of dislocations during epitaxial deposition of Si-rich Si{sub 1-x}Ge{sub x} alloys, preferentially gettering misfit segments along pit rows. In particular, for a 250 nm layer deposited by molecular beam epitaxy at x{sub Ge} = 15%, extended film regions appear free of dislocations, by atomic force microscopy, as confirmed by transmission electron microscopy sampling. This result is quite general, as explained by dislocation dynamics simulations, which reveal the key role of the inhomogeneous distribution in stress produced by the pit-patterning.

  2. Effects of (Al,Ge) double doping on the thermoelectric properties of higher manganese silicides

    SciTech Connect (OSTI)

    Chen, Xi; Salta, Daniel; Zhang, Libin [Materials Science and Engineering Program, Texas Materials Institute, The University of Texas at Austin, Austin, Texas 78712 (United States); Weathers, Annie [Department of Mechanical Engineering, The University of Texas at Austin, Austin, Texas 78712 (United States); Zhou, Jianshi; Goodenough, John B.; Shi, Li [Materials Science and Engineering Program, Texas Materials Institute, The University of Texas at Austin, Austin, Texas 78712 (United States); Department of Mechanical Engineering, The University of Texas at Austin, Austin, Texas 78712 (United States)

    2013-11-07

    Experiments and analysis have been carried out to investigate the effects of Al and (Al,Ge) doping on the microstructure and thermoelectric properties of polycrystalline higher manganese silicide (HMS) samples, which were prepared by solid-state reaction, ball milling, and followed by spark plasma sintering. It has been found that Al doping effectively increases the hole concentration, which leads to an increase in the electrical conductivity and power factor. By introducing the second dopant Ge into Al-doped HMS, the electrical conductivity is increased, and the Seebeck coefficient is decreased as a result of further increased hole concentration. The peak power factor is found to occur at a hole concentration between 1.8?×?10{sup 21} and 2.2?×?10{sup 21}?cm{sup ?3} measured at room temperature. The (Al,Ge)-doped HMS samples show lower power factors owing to their higher hole concentrations. The mobility of Mn(Al{sub 0.0035}Ge{sub y}Si{sub 0.9965-y}){sub 1.8} with y?=?0.035 varies approximately as T{sup ?3/2} above 200?K, suggesting acoustic phonon scattering is the dominant scattering mechanism. The thermal conductivity of HMS does not change appreciably by Al or (Al,Ge) doping. The maximum ZT of (Al,Ge)-doped HMS is 0.57 at 823?K, which is similar to the highest value found in the Al-doped HMS samples. The ZT values were reduced in the Mn(Al{sub 0.0035}Ge{sub y}Si{sub 0.9965-y}){sub 1.8} samples with high Ge concentration of y?=?0.025 and 0.035, because of reduced power factor. In addition, a two-band model was employed to show that the hole contribution to the thermal conductivity dominates the bipolar and electron contributions for all samples from 300 to 823?K and accounts for about 12% of the total thermal conductivity at about 800?K.

  3. Absolute Drell-Yan Dimuon Cross Sections in 800 GeV/c pp and pd Collisions

    E-Print Network [OSTI]

    FNAL E866/NuSea Collaboration; :; J. C. Webb; T. C. Awes; M. L. Brooks; C. N. Brown; J. D. Bush; T. A. Carey; T. H. Chang; W. E. Cooper; C. A. Gagliardi; G. T. Garvey; D. F. Geesaman; E. A. Hawker; X. C. He; L. D. Isenhower; D. M. Kaplan; S. B. Kaufman; D. D. Koetke; D. M. Lee; W. M. Lee; M. J. Leitch; N. Makins; P. L. McGaughey; J. M. Moss; B. A. Mueller; P. M. Nord; V. Papavassiliou; B. K. Park; J. C. Peng; G. Petitt; P. E. Reimer; M. E. Sadler; W. E. Sondheim; P. W. Stankus; T. N. Thompson; R. S. Towell; R. E. Tribble; M. A. Vasiliev; J. L. Willis; D. K. Wise; G. R. Young

    2003-02-14

    The Fermilab E866/NuSea Collaboration has measured the Drell-Yan dimuon cross sections in 800 GeV/$c$ $pp$ and $pd$ collisions. This represents the first measurement of the Drell-Yan cross section in $pp$ collisions over a broad kinematic region and the most extensive study to date of the Drell-Yan cross section in $pd$ collisions. The results indicate that recent global parton distribution fits provide a good description of the light antiquark sea in the nucleon over the Bjorken-$x$ range $0.03 \\lesssim x < 0.15$, but overestimate the valence quark distributions as $x \\to 1$.

  4. Cross-sections of large-angle hadron production in proton- and pion-nucleus interactions II: beryllium nuclei and beam momenta from +/- 3 GeV/c to +/-15 GeV/c

    E-Print Network [OSTI]

    The HARP-CDP group; :; A. Bolshakova

    2009-06-23

    We report on double-differential inclusive cross-sections of the production of secondary protons and charged pions, in the interactions with a 5% interaction length thick stationary beryllium target, of proton and pion beams with momentum from +/-3 GeV/c to +/-15 GeV/c. Results are given for secondary particles with production angles between 20 and 125 degrees.

  5. Page 320 Courses: Geology (GEOL) Sonoma State University 2010-2011 Catalog GeOl 303 AdVAnCed prinCipleS Of GeOlOGy (4)

    E-Print Network [OSTI]

    Ravikumar, B.

    Page 320 Courses: Geology (GEOL) Sonoma State University 2010-2011 Catalog GeOl 303 AdVAnCed prinCipleS Of GeOlOGy (4) Lecture, 3 hours; laboratory, 3 hours. Advanced treatment of the principles, meth- ods and tools of geology emphasizing the materials that constitute the earth and the processes that act or have

  6. Low-temperature (180?°C) formation of large-grained Ge (111) thin film on insulator using accelerated metal-induced crystallization

    SciTech Connect (OSTI)

    Toko, K., E-mail: toko@bk.tsukuba.ac.jp; Numata, R.; Oya, N.; Suemasu, T. [Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573 (Japan); Fukata, N. [National Institute for Materials Science, Namiki, Tsukuba 305-0044 (Japan); Usami, N. [Materials, Physics and Energy Engineering, Nagoya University, Aichi 464-8603 (Japan)

    2014-01-13

    The Al-induced crystallization (AIC) yields a large-grained (111)-oriented Ge thin film on an insulator at temperatures as low as 180?°C. We accelerated the AIC of an amorphous Ge layer (50-nm thickness) by initially doping Ge in Al and by facilitating Ge diffusion into Al. The electron backscatter diffraction measurement demonstrated the simultaneous achievement of large grains over 10??m and a high (111) orientation fraction of 90% in the polycrystalline Ge layer formed at 180?°C. This result opens up the possibility for developing Ge-based electronic and optical devices fabricated on inexpensive flexible substrates.

  7. Large grain growth of Ge-rich Ge{sub 1?x}Sn{sub x} (x???0.02) on insulating surfaces using pulsed laser annealing in flowing water

    SciTech Connect (OSTI)

    Kurosawa, Masashi, E-mail: kurosawa@alice.xtal.nagoya-u.ac.jp [Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); JSPS, 5-3-1 Kojimachi, Chiyoda-ku, Tokyo 102-0083 (Japan); Taoka, Noriyuki; Nakatsuka, Osamu; Zaima, Shigeaki [Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Ikenoue, Hiroshi [Graduate School of Information Science and Electrical Engineering, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan)

    2014-02-10

    We investigate Sn incorporation effects on the growth characteristics of Ge-rich Ge{sub 1?x}Sn{sub x} (x?GeSn layers play a role in preventing ablation and aggregation of the layers during these PLA. Raman and electron backscatter diffraction measurements demonstrate achievement of large-grain (?800?nm?) growth of Ge{sub 0.98}Sn{sub 0.02} polycrystals by using PLA in water. These polycrystals also show a tensile-strain of ?0.68%. This result opens up the possibility for developing GeSn-based devices fabricated on flexible substrates as well as Si platforms.

  8. Crystal structure and physical properties of quaternary clathrates Ba{sub 8}Zn{sub x}Ge{sub 46-x-y}Si{sub y}, Ba{sub 8}(Zn,Cu){sub x}Ge{sub 46-x} and Ba{sub 8}(Zn,Pd){sub x}Ge{sub 46-x}

    SciTech Connect (OSTI)

    Nasir, Navida; Grytsiv, Andriy; Melnychenko-Koblyuk, Nataliya [Institute of Physical Chemistry, University of Vienna, A-1090 Wien (Austria); Rogl, Peter, E-mail: peter.franz.rogl@univie.ac.a [Institute of Physical Chemistry, University of Vienna, A-1090 Wien (Austria); Bednar, Ingeborg; Bauer, Ernst [Institute of Solid State Physics, Vienna University of Technology, A-1040 Wien (Austria)

    2010-10-15

    Three series of vacancy-free quaternary clathrates of type I, Ba{sub 8}Zn{sub x}Ge{sub 46-x-y}Si{sub y}, Ba{sub 8}(Zn,Cu){sub x}Ge{sub 46-x}, and Ba{sub 8}(Zn,Pd){sub x}Ge{sub 46-x}, have been prepared by reactions of elemental ingots in vacuum sealed quartz at 800 {sup o}C. In all cases cubic primitive symmetry (space group Pm3n, a{approx}1.1 nm) was confirmed for the clathrate phase by X-ray powder diffraction and X-ray single crystal analyses. The lattice parameters show a linear increase with increase in Ge for Ba{sub 8}Zn{sub x}Ge{sub 46-x-y}Si{sub y}. M atoms (Zn, Pd, Cu) preferably occupy the 6d site in random mixtures. No defects were observed for the 6d site. Site preference of Ge and Si in Ba{sub 8}Zn{sub x}Ge{sub 46-x-y}Si{sub y} has been elucidated from X-ray refinement: Ge atoms linearly substitute Si in the 24k site whilst a significant deviation from linearity is observed for occupation of the 16i site. A connectivity scheme for the phase equilibria in the 'Ba{sub 8}Ge{sub 46}' corner at 800 {sup o}C has been derived and a three-dimensional isothermal section at 800 {sup o}C is presented for the Ba-Pd-Zn-Ge system. Studies of transport properties carried out for Ba{sub 8{l_brace}}Cu,Pd,Zn{r_brace}{sub x}Ge{sub 46-x} and Ba{sub 8}Zn{sub x}Si{sub y}Ge{sub 46-x-y} evidenced predominantly electrons as charge carriers and the closeness of the systems to a metal-to-insulator transition, fine-tuned by substitution and mechanical processing of starting material Ba{sub 8}Ge{sub 43}. A promising figure of merit, ZT {approx}0.45 at 750 K, has been derived for Ba{sub 8}Zn{sub 7.4}Ge{sub 19.8}Si{sub 18.8}, where pricey germanium is exchanged by reasonably cheap silicon. - Graphical abstract: Quaternary phase diagram of Ba-Pd-Zn-Ge system at 800 {sup o}C.

  9. Study of Centrality Dependence of Transverse Momentum Spectra of Hadrons and the Freeze-out Parameters at root(sNN) of 62.4 GeV, 130 GeV and 200 GeV

    E-Print Network [OSTI]

    Saeed Uddin; Riyaz Ahmed Bhat; Inam-ul Bashir

    2014-12-05

    We attempt to describe the rapidity distribution of P, P-bar, K+ and K- for the most central Au+Au collisions at root(sNN) of 62.4 GeV,130 GeV and 200 GeV. The transverse momentum spectra of strange as well as non-strange hadrons e.g. P, P-bar, K+, K-, Lambda, Lambda-bar, Cascade,Cascade-bar and (Omega + Omega-bar) are studied for the whole centrality classes at all the three RHIC energies. The experimental data of the transverse momentum spectra and the rapidity distributions are well reproduced. This is done by using a statistical thermal freeze-out model which incorporates the rapidity (collision) axis as well as transverse direction boosts developed within an expanding hot and dense hadronic fluid (fireball) till the final freeze-out. We determine the thermo-chemical freeze-out conditions particularly in terms of temperature, baryon chemical potential and collective flow effect parameters for different particle species. The parameters indicate occurrence of freeze-out of the singly and doubly strange hyperon species at somewhat earlier times during the evolution of the fireball. Dependence of the freeze-out parameters on the degree of centrality is also described and it is found that the kinetic temperature increases and collective flow effect decreases with decreasing centrality at all energies studied. The nuclear transparency effect is also studied and it is clear from our model that the nuclear matter becomes more transparent at the highest RHIC energy compared to lower RHIC energies. The contribution of heavier hadronic resonance decay is taken into account.

  10. The interfacial reaction of Ni on (100) Si?â??xGex (x=0, 0.25) and (111) Ge

    E-Print Network [OSTI]

    Jin, Lijuan

    The interfacial reaction of Ni with Si, Si?.??Ge?.??, and Ge at 400°C has been investigated. A uniform epitaxial NiSi film was obtained at 400°C for Ni-Silicidation on Si using rapid thermal annealing method. Similarly, ...

  11. Effects of carbon on phosphorus diffusion in SiGe:C and the implications on phosphorus diffusion mechanisms

    SciTech Connect (OSTI)

    Lin, Yiheng; Xia, Guangrui [Department of Materials Engineering, The University of British Columbia, 309-6350 Stores Rd, Vancouver, British Columbia V6T 1Z4 (Canada); Yasuda, Hiroshi; Wise, Rick [Texas Instruments, 13121 TI Blvd., Dallas, Texas 75243 (United States); Schiekofer, Manfred; Benna, Bernhard [Texas Instruments Deutschland GmbH, Haggertystrasse 1, 85356 Freising (Germany)

    2014-10-14

    The use of carbon (C) in SiGe base layers is an important approach to control the base layer dopant phosphorus (P) diffusion and thus enhance PNP heterojunction bipolar transistor (HBT) performance. This work quantitatively investigated the carbon impacts on P diffusion in Si?.??Ge?.??:C and Si:C under rapid thermal anneal conditions. The carbon molar fraction is up to 0.32%. The results showed that the carbon retardation effect on P diffusion is less effective for Si?.??Ge?.??:C than for Si:C. In Si?.??Ge?.??:C, there is an optimum carbon content at around 0.05% to 0.1%, beyond which more carbon incorporation does not retard P diffusion any more. This behavior is different from the P diffusion behavior in Si:C and the B in Si:C and low Ge SiGe:C, which can be explained by the decreased interstitial-mediated diffusion fraction f{sub I}{sup P,SiGe} to 95% as Ge content increases to 18%. Empirical models were established to calculate the time-averaged point defect concentrations and effective diffusivities as a function of carbon and was shown to agree with previous studies on boron, phosphorus, arsenic and antimony diffusion with carbon.

  12. FILE CPO-a-.... l~a.yii GE DOCUMENT NO. 80SDS4230 DEVELOPMENT AND DEMONSTRATION

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    FILE CPO¥-a-.... l£~a.yii GE DOCUMENT NO. 80SDS4230 DEVELOPMENT AND DEMONSTRATION OF A 31~STIRLING Government or any agency thereof. #12;GE DOCUMENT NO. 80SDS4230 DEVELOPMENT AND DEMONSTRATION OF STIRLING . . . . . . 3-16 3.3 Engine . . . . . . . . . . . . . . . . . . 3-16 3.3.1 Summary . . . . . . . . . . . . . . 3

  13. Proposed structure for a crossed-laser beam, GeV per meter gradient, vacuum electron linear accelerator

    E-Print Network [OSTI]

    Byer, Robert L.

    Proposed structure for a crossed-laser beam, GeV per meter gradient, vacuum electron linear We propose a dielectric-based, multistaged, laser-driven electron linear accelerator structure operating in a vacuum that is capable of accelerating electrons to 1 TeV in 1 km. Our study shows that a Ge

  14. 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

  15. Direct photons in 200 GeV p+p, d+Au, and Au+Au from PHENIX

    E-Print Network [OSTI]

    Stefan Bathe; for the PHENIX Collaboration

    2005-11-22

    Direct photons were measured with the PHENIX experiment in p+p, d+Au, and Au+Au at sqrt(s_NN) = 200 GeV. To tackle the p_T region below 5 GeV/c, direct photons were measured through their internal conversion into e^+e^- in Au+Au collisions.

  16. Role of hydrogen in Ge/HfO2/Al gate stacks subjected to negative bias temperature instability

    E-Print Network [OSTI]

    Misra, Durgamadhab "Durga"

    Role of hydrogen in Ge/HfO2/Al gate stacks subjected to negative bias temperature instability N 2007; published online 17 January 2008 This work investigates the role of hydrogen and nitrogen in a Ge. Virtually unchanged interface state density as a function of NBTI indicates no atomic hydrogen release from

  17. Stability and equation of state of the post-perovskite phase in MgGeO3 Atsushi Kubo,1

    E-Print Network [OSTI]

    Duffy, Thomas S.

    Stability and equation of state of the post-perovskite phase in MgGeO3 to 2 Mbar Atsushi Kubo,1 and equation of state of the post- perovskite phase in MgGeO3 were investigated to 2 Mbar by in situ x. The relative axial compressibilities of the silicate and germanate post-perovskite phases are similar although

  18. Planar waveguide obtained by burying a Ge22As20Se58 fiber in As2S3 glass

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Planar waveguide obtained by burying a Ge22As20Se58 fiber in As2S3 glass Quentin Coulombier glasses. Two highly mature chalcogenide glasses are used for these experiments. GASIR glass from Umicore IR Glass, Olen, Belgium, with the composition of Ge22As20Se58 is used to draw fibers

  19. Neutral pion production in Au plus Au collisions at root s(NN)=200 GeV

    E-Print Network [OSTI]

    Walker, M.

    The results of midrapidity (0GeV/c) in ?(s[subscript NN])=200?GeV?Au+Au collisions, measured by the STAR experiment, are presented. ...

  20. Particle Production of Carbon Target with 20Tto2T5m Configuration at 6.75 GeV

    E-Print Network [OSTI]

    McDonald, Kirk

    Particle Production of Carbon Target with 20Tto2T5m Configuration at 6.75 GeV (Preliminary) Xm; · Production Collection: (1.2 m downstream, 40 MeV production threshold kinetic energy (Default:0.03 GeV); EMCHR: The threshold energy applied collectively

  1. Quantum modeling of thermoelectric performance of strained Si/Ge/Si superlattices using the nonequilibrium Green's function method

    E-Print Network [OSTI]

    Walker, D. Greg

    Quantum modeling of thermoelectric performance of strained Si/Ge/Si superlattices using 2007 The cross-plane thermoelectric performance of strained Si/Ge/Si superlattices is studied from such that thermoelectric performance is independent of layer thickness between 2 and 4 nm germanium barrier layers

  2. (Sr,Ba)(Si,Ge){sub 2} for thin-film solar-cell applications: First-principles study

    SciTech Connect (OSTI)

    Kumar, Mukesh E-mail: mkgarg79@gmail.com; Umezawa, Naoto; Imai, Motoharu

    2014-05-28

    In order to meet the increasing demand for electric power generation from solar energy conversion, the development of efficient light absorber materials has been awaited. To this end, the electronic and optical properties of advanced alkaline-earth-metals disilicides and digermanides (SrSi{sub 2}, BaSi{sub 2}, SrGe{sub 2}, and BaGe{sub 2}) are studied by means of the density functional theory using HSE06 exchange-correlation energy functional. Our calculations show that all these orthorhombic structured compounds have fundamental indirect band gaps in the range E{sub g} ? 0.89–1.25 eV, which is suitable for solar cell applications. The estimated lattice parameters and band gaps are in good agreement with experiments. Our calculations show that the electronic band structures of all four compounds are very similar except in the vicinity of the ?-point. The valence band of these compounds is made up by Si(Ge)-p states, whereas the conduction band is composed of Sr(Ba)-d states. Their band alignments are carefully determined by estimating the work function of each compound using slab model. The optical properties are discussed in terms of the complex dielectric function ?(?)?=??{sub 1}(?)?+?i?{sub 2}(?). The static and high-frequency dielectric constants are calculated, taking into account the ionic contribution. The absorption coefficient ?(?) demonstrates that a low energy dispersion of the conduction band, which results in a flat conduction band minimum, leads to large optical activity in these compounds. Therefore, alkaline-earth-metals disilicides and digermanides possess great potential as light absorbers for applications in thin-film solar cell technologies.

  3. Dispersive estimates of solutions to the Schrodinger equation in dimensions $n\\ge 4$

    E-Print Network [OSTI]

    Georgi Vodev

    2006-02-03

    We prove dispersive estimates for solutions to the Schrodinger equation with a real-valued potential $V\\in L^\\infty({\\bf R}^n)$, $n\\ge 4$, satisfying $V(x)=O(|x|^{-(n+2)/2-\\epsilon})$, $|x|>1$, $\\epsilon>0$.

  4. Atomic and electronic structure of the ferroelectric BaTiO{sub 3}/Ge(001) interface

    SciTech Connect (OSTI)

    Fredrickson, Kurt D.; Ponath, Patrick; Posadas, Agham B.; Demkov, Alexander A., E-mail: demkov@physics.utexas.edu [Department of Physics, The University of Texas at Austin, Austin, Texas 78712 (United States); McCartney, Martha R.; Smith, David J. [Department of Physics, Arizona State University, Tempe, Arizona 85287 (United States); Aoki, Toshihiro [LeRoy Eyring Center for Solid State Science, Arizona State University, Tempe, Arizona 85287 (United States)

    2014-06-16

    In this study, we demonstrate the epitaxial growth of BaTiO{sub 3} on Ge(001) by molecular beam epitaxy using a thin Zintl template buffer layer. A combination of density functional theory, atomic-resolution electron microscopy and in situ photoemission spectroscopy is used to investigate the electronic properties and atomic structure of the BaTiO{sub 3}/Ge interface. Aberration-corrected scanning transmission electron micrographs reveal that the Ge(001) 2?×?1 surface reconstruction remains intact during the subsequent BaTiO{sub 3} growth, thereby enabling a choice to be made between several theoretically predicted interface structures. The measured valence band offset of 2.7?eV matches well with the theoretical value of 2.5?eV based on the model structure for an in-plane-polarized interface. The agreement between the calculated and measured band offsets, which are highly sensitive to the detailed atomic arrangement, indicates that the most likely BaTiO{sub 3}/Ge(001) interface structure has been identified.

  5. GeV ELECTRON BEAMS FROM A CENTIMETER-SCALE LASER-DRIVEN PLASMA ACCELERATOR

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    GeV ELECTRON BEAMS FROM A CENTIMETER-SCALE LASER-DRIVEN PLASMA ACCELERATOR A. J. Gonsalves, K discharge waveguide [1, 2]. Electron beams were not observed without a plasma channel, indicating that self of the electron beam spectra, and the dependence of the reliability of pro- ducing electron beams as a function

  6. High-speed SiGe BiCMOS technologies for Ethernet communications

    E-Print Network [OSTI]

    Weinreb, Sander

    High-speed SiGe BiCMOS technologies for Ethernet communications from 10Gb/s to 100Gb/s Pascal Characterization, Modeling, Design, ... involved in the development of High-Speed BiCMOS technologies Thanks-offs 43 · Reliability 46 Technology of high-speed HBTs · Architectures 50 · Competitors 66 · Device

  7. Plasma hydrogenation of strain-relaxed SiGe/Si heterostructure for layer transfer

    SciTech Connect (OSTI)

    Chen Peng; Chu, Paul K.; Hoechbauer, T.; Nastasi, M.; Buca, D.; Mantl, S.; Theodore, N. David; Alford, T.L.; Mayer, J.W.; Loo, R.; Caymax, M.; Cai, M.; Lau, S.S. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China); Los Alamos National Laboratory, Los Alamos, New Mexico, 87545 (United States); Institut fuer Schichten und Grenzflaechen and cni-Center of Nanoelectronic Systems for Information Technology, Forschungszentrum Juelich, D-52425 Juelich (Germany); Advanced Products Research and Development Laboratory, Freescale Semiconductor Incorporated, 2100 East Elliot Road, Tempe, Arizona 85284 (United States); Department of Chemical and Materials Engineering, Arizona State University, Tempe, Arizona 85287 (United States); IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); University of California at San Diego, San Diego, California 92093 (United States)

    2004-11-22

    The use of plasma hydrogenation for relaxed SiGe layer transfer is demonstrated. It is found that the interface of a strain-relaxed SiGe/Si heterostructure is effective in trapping H during plasma hydrogenation. Long microcracks observed at the interface due to the trapping of indiffused H indicate the distinct possibility of transferring the overlayer using the ion-cutting technique. Our results suggest that interfacial defects induced by the He implantation relaxation process trap the indiffusing H atoms and lead to interfacial cracks during hydrogenation or upon postannealing at higher temperatures. It is further noted that trapping of H at the interface is possible only in strain-relaxed structures. Without strain relaxation, H atoms introduced by plasma hydrogenation get trapped just below the sample surface and form a band of shallow platelets. Without the need for high-dose high-energy ion implantation, our results suggest an effective way for high-quality strain-relaxed SiGe layer transfer. The technique has potential for application in the fabrication of SiGe-on-insulator strained Si epitaxial layer and related structures.

  8. DOI: 10.1002/adma.200801764 Low-Temperature Deterministic Growth of Ge Nanowires

    E-Print Network [OSTI]

    Jo, Moon-Ho

    DOI: 10.1002/adma.200801764 Low-Temperature Deterministic Growth of Ge Nanowires Using Cu Solid-dimensional crystal growth essentially exploits the highly asymmetric growth kinetics in the radial and axial and the subsequent one-dimensional crystal growth.[1­3] One of the earliest and prevailing examples of such one

  9. Magnetic structure at low temperatures in FeGe{sub 2}

    SciTech Connect (OSTI)

    Babu, P. D.; Mishra, P. K.; Dube, V.; Ravikumar, G.; Mishra, R.; Sastry, P. U.

    2014-04-24

    Magnetic phase of FeGe{sub 2} intermetallic is studied using low-temperature neutron diffraction and DC magnetization. Zero-magnetic-field neutron scattering data shows the presence of an antiferromagnetic phase in the low temperature range. We find the evidence of the presence of a ferromagnetic order overriding on the predominantly antiferromagnetic phase at low temperatures.

  10. $?_{DIS}(?N)$, NLO Perturbative QCD and O(1 GeV) Mass Corrections

    E-Print Network [OSTI]

    S. Kretzer; M. H. Reno

    2004-10-13

    The deep-inelastic neutrino-nucleon cross section is one of the components of few GeV neutrino interactions. We present here our results for neutrino-isoscalar nucleon charged current scattering including perturbative next-to-leading order QCD corrections, target mass corrections, charm mass and lepton mass corrections.

  11. Forward Di-hadron Asymmetries from p + p at ?s = 200 GeV at STAR 

    E-Print Network [OSTI]

    Drachenberg, James Lucas

    2012-07-16

    to Interference Fragmentation Functions (IFF) and the Sivers effect. In 2008, RHIC dedicated a portion of the run to transversely polarized proton collisions at sqrt(s) = 200 GeV. STAR was equipped with a Foward Meson Spectrometer (FMS) and a Forward Time...

  12. Effect of carbon doping on electronic transitions in Mn5Ge3 N. Stojilovic,1,a)

    E-Print Network [OSTI]

    Dordevic, Sasha V.

    these compounds promising candidates for spin injectors for potential spintronics applications. The resistivity mismatch between a metal and a semicon- ductor. Therefore, for spintronics applications, finding a compound is now being considered for use in spintronics applications.4 However, pure Mn5Ge3 has Tc ¼ 293 K,5 which

  13. Higgs-Portal Dark Matter for GeV Gamma-Ray Excess

    E-Print Network [OSTI]

    P. Ko; Wan-Il Park; Yong Tang

    2015-04-27

    We present Higgs-Portal dark matter (DM) models to explain the reported Galactic Center GeV gamma-ray excess. Naive effective theories are inconsistent with direct detection constraint for the relevant parameter range. Simple extended models with dark gauge symmetries can easily accommodate the gamma-ray excess through the Higgs-Portal coupling while satisfying various constraints.

  14. 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

  15. A search for GeV-TeV emission from GRBs with the Milagro detector

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    in the three years since the launch of Swift. Keywords: gamma-ray sources; gamma-ray bursts; astronomical observations gamma-ray PACS: 98.70.Rz,95.85.Pw Gamma-ray bursts (GRBs) have been detected up to GeV energies. B. Yodh CPIOOO, Gamma-Ray Bursts 2007: Proceedings of the Santa Fe Conference, edited by M. Galassi

  16. 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

  17. GREEN FUNCTIONS ASSOCIATED TO COMPLEX REFLECTION GROUPS G(e, 1, n)

    E-Print Network [OSTI]

    Shoj, Toshiaki

    of the matrix P give Green functions Q # (u)). Note that the matrix# is completely determined by the property characters, is completely dominated by Green functions. Thanks to Lusztig [L3], similar facts hold in generalGREEN FUNCTIONS ASSOCIATED TO COMPLEX REFLECTION GROUPS G(e, 1, n) TOSHIAKI SHOJI Department

  18. GREEN FUNCTIONS ASSOCIATED TO COMPLEX REFLECTION GROUPS G(e, 1, n)

    E-Print Network [OSTI]

    Shoj, Toshiaki

    P give Green functions QO(u)). No* *te that the matrix is completely determined by the property to the values at unipotent elements of unipotent characters, is completely domi* *nated by Green functions GREEN FUNCTIONS ASSOCIATED TO COMPLEX REFLECTION GROUPS G(e, 1, n

  19. GeV electron beams from a centimetre-scale accelerator

    E-Print Network [OSTI]

    to synchrotron radiation facilities and free-electron lasers, and as modules for high-energy particle physics. Radiofrequency-based accelerators are limited to relatively low accelerating fields (10-50 MV m-1 ), requiring tens to hundreds of metres to reach the multi-GeV beam energies needed to drive radiation sources

  20. The 8-GeV transfer line injection into main ring

    SciTech Connect (OSTI)

    Yang, M.J.

    1995-06-01

    Included in this report are a brief review of the design lattice of the 8-GeV beam transfer line and the Main Ring, the recent measurements on the 8-GeV line lattice function as well as that of the Main Ring at 8-GeV. The injection matching is a very important part of the MR operation. Mismatches such as energy, timing, or position are easily corrected because they cause oscillations which are visible on the Turn-By-Turn (TBT) TV monitor display. Mis-matches due to beta and dispersion functions are detected only by using the Flying Wire or by doing measurements during beam study. A new method which makes use of the available data from TBT hardware was used to obtain the beam phase space ellipse. Data taken from Main Ring at injection gives the beta function needed for transfer matching from 8-GeV line. The result of this measurement is also presented here.

  1. A Search for GeV-TeV Emission from GRBs Using the Milagro Detector

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    with known redshift is reported. Keywords: -ray, -ray bursts, -ray telescope PACS: 95.85.Pw 98.70.Rz 95.55.Ka INTRODUCTION Milagro is ground-based gamma-ray observatory located in the Jemez mountains (2630 m a to search for >1 GeV emission from these bursts. Milagro is a water Cerenkov detector designed primarily

  2. SERA-IO: Integrating Energy Consciousness into Parallel I/O Middleware Rong Ge Xizhou Feng

    E-Print Network [OSTI]

    Sun, Xian-He

    .ge@marquette.edu xizhou.feng@marquette.edu Xian-He Sun Department of Computer Science Illinois Institute of Technology, Chicago, IL sun@iit.edu Abstract--Improving energy efficiency is a primary concern in high performance on modern processors to intelligently schedule the system's power-performance mode for energy savings. We

  3. Measurements of the Cosmic-Ray Positron Fraction From 1 to 50 GeV

    E-Print Network [OSTI]

    HEAT Collaboration; S. W. Barwick; E. Schneider; J. J. Beatty; G. A. de Nolfo; A. Bhattacharyya; C. R. Bower; J. A. Musser; C. J. Chaput; S. Coutu; S. McKee; G. Tarle; A. D. Tomasch; J. Knapp; D. M. Lowder; D. Muller; S. P. Swordy; E. Torbet; S. L. Nutter

    1997-03-28

    Two measurements of the cosmic-ray positron fraction as a function of energy have been made using the High Energy Antimatter Telescope (HEAT) balloon-borne instrument. The first flight took place from Ft. Sumner, New Mexico in 1994, and yielded results above the geomagnetic cutoff energy of 4.5 GeV. The second flight from Lynn Lake, Manitoba in 1995 permitted measurements over a larger energy interval, from 1 GeV to 50 GeV. In this letter we present results on the positron fraction based on data from the Lynn Lake flight, and compare these with the previously published results from the Ft. Sumner flight. The results confirm that the positron fraction does not increase with energy above ~10 GeV, although a small excess above purely secondary production cannot be ruled out. At low energies the positron fraction is slightly larger than that reported from measurements made in the 1960's. This effect could possibly be a consequence of charge dependence in the level of solar modulation.

  4. 1 | Building America eere.energy.gov Evaluation of Ducted GE

    E-Print Network [OSTI]

    1 | Building America eere.energy.gov Evaluation of Ducted GE Hybrid Heat Pump Water Heater in PNNL Lab Homes Sarah Widder Building America Program Review April 24-25, 2013 #12;2 | Building America eere Technologies Program ­ DOE, Office of Electricity Project Partners #12;3 | Building America eere

  5. Energy deposition of 24 GeV/c protons in gravity affected

    E-Print Network [OSTI]

    McDonald, Kirk

    Energy deposition of 24 GeV/c protons in gravity affected mercury jet Sergei Striganov Fermilab Data Analysis(latest update : 07Oct08), including dispersion term. · If there is vacuum only between +- 15 degree 75 +- 15 degree #12;Energy deposition density in round gravity affected jet at 5 Tesla, r=8

  6. ? cross section in p+p collisions at ?s=200??GeV

    E-Print Network [OSTI]

    Balewski, Jan T.

    We report on a measurement of the ?(1S+2S+3S)?e+e- cross section at midrapidity in p+p collisions at ?s=200??GeV. We find the cross section to be 114±38(stat+fit)-24+23(syst)??pb. Perturbative QCD calculations at next-to-leading ...

  7. Fabrication and Testing Status of CEBAF 12 GeV Upgrade Cavities

    SciTech Connect (OSTI)

    Marhauser, F; Davis, G K; Forehand, D; Grenoble, C; Hogan, J; Overton, R B; Reilly, A V; Rimmer, R A

    2011-09-01

    The 12 GeV upgrade of the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Laboratory (JLab) is under way. All cavities have been built by industry and are presently undergoing post-processing and final low and high power qualification before cryomodule assembly. The status is reported including fabrication-related experiences, observations and issues throughout production, post-processing and qualification.

  8. Continuum charged D* spin alignment at s?=10.5GeV

    E-Print Network [OSTI]

    Ammar, Raymond G.; Baringer, Philip S.; Bean, Alice; Besson, David Zeke; Coppage, Don; Darling, C.; Davis, Robin E. P.; Kotov, S.; Kravchenko, I.; Kwak, Nowhan; Zhou, L.

    1998-07-29

    A measurement of the spin alignment of charged D* mesons produced in continuum e+e-?cc¯ events at s?=10.5GeV is presented. This study using 4.72fb(-1) of CLEO II data shows that there is little evidence of any D* spin alignment.

  9. Strange particle production in p+p collisions at root s=200 Ge

    E-Print Network [OSTI]

    Abelev, B. I.; Adams, J.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D.; Anderson, M.; Arkhipkin, D.; Averichev, G. S.; Bai, Y.; Balewski, J.; Barannikova, O.; Barnby, L. S.; Baudot, J.; Bekele, S.; Belaga, V. V.; Bellingeri-Laurikainen, A.; Bellwied, R.; Benedosso, F.; Bhardwaj, S.; Bhasin, A.; Bhati, A. K.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Blyth, S. -L; Bonner, B. E.; Botje, M.; Bouchet, J.; Brandin, A. V.; Bravar, A.; Burton, T. P.; Bystersky, M.; Cadman, R. V.; Cai, X. Z.; Caines, H.; Calderon de la Barca Sanchez,M.; Castillo, J.; Catu, O.; Cebra, D.; Chajecki, Z.; Chaloupka, P.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Coffin, J. P.; Cormier, T. M.; Cosentino, M. R.; Cramer, J. G.; Crawford, H. J.; Das, D.; Das, S.; Dash, S.; Daugherity, M.; de Moura, M. M.; Dedovich, T. G.; DePhillips, M.; Derevschikov, A. A.; Didenko, L.; Dietel, T.; Djawotho, P.; Dogra, S. M.; Dong, W. J.; Dong, X.; Draper, J. E.; Du, F.; Dunin, V. B.; Dunlop, J. C.; Dutta Mazumdar, M. R.; Eckardt, V.; Edwards, W. R.; Efimov, L. G.; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Fachini, P.; Fatemi, R.; Fedorisin, J.; Filimonov, K.; Filip, P.; Finch, E.; Fine, V.; Fisyak, Y.; Fu, J.; Gagliardi, Carl A.; Gaillard, L.; Ganti, M. S.; Ghazikhanian, V.; Ghosh, P.; Gonzalez, J. E.; Gorbunov, Y. G.; Gos, H.; Grebenyuk, O.; Grosnick, D.; Guertin, S. M.; Guimaraes, K. S. F. F.; Gupta, A.; Gutierrez, T. D.; Haag, B.; Hallman, T. J.; Hamed, A.; Harris, J. W.; He, W.; Heinz, M.; Henry, T. W.; Hepplemann, S.; Hippolyte, B.; Hirsch, A.; Hjort, E.; Hoffman, A. M.; Hoffmann, G. W.; Horner, M. J.; Huang, H. Z.; Huang, S. L.; Hughes, E. W.; Humanic, T. J.; Igo, G.; Jacobs, P.; Jacobs, W. W.; Jakl, P.; Jia, F.; Jiang, H.; Jones, P. G.; Judd, E. G.; Kabana, S.; Kang, K.; Kapitan, J.; Kaplan, M.; Keane, D.; Kechechyan, A.; Khodyrev, V. Yu; Kim, B. C.; Kiryluk, J.; Kisiel, A.; Kislov, E. M.; Klein, S. R.; Kocoloski, A.; Koetke, D. D.; Kollegger, T.; Kopytine, M.; Kotchenda, L.; Kouchpil, V.; Kowalik, K. L.; Kramer, M.; Kravtsov, P.; Kravtsov, V. I.; Krueger, K.; Kuhn, C.; Kulikov, A. I.; Kumar, A.; Kuznetsov, A. A.; Lamont, M. A. C.; Landgraf, J. M.; Lange, S.; LaPointe, S.; Laue, F.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, C. -H; Lehocka, S.; LeVine, M. J.; Li, C.; Li, Q.; Li, Y.; Lin, G.; Lin, X.; Lindenbaum, S. J.; Lisa, M. A.; Liu, F.; Liu, H.; Liu, J.; Liu, L.; Liu, Z.; Ljubicic, T.; Llope, W. J.; Long, H.; Longacre, R. S.; Love, W. A.; Lu, Y.; Ludlam, T.; Lynn, D.; Ma, G. L.; Ma, J. G.; Ma, Y. G.; Magestro, D.; Mahapatra, D. P.; Majka, R.; Mangotra, L. K.; Manweiler, R.; Margetis, S.; Markert, C.; Martin, L.; Matis, H. S.; Matulenko, Yu A.; McClain, C. J.; McShane, T. S.; Melnick, Yu; Meschanin, A.; Millane, J.; Miller, M. L.; Minaev, N. G.; Mioduszewski, Saskia; Mironov, C.; Mischke, A.; Mishra, D. K.; Mitchell, J.; Mohanty, B.; Molnar, L.; Moore, C. F.; Morozov, D. A.; Munhoz, M. G.; Nandi, B. K.; Nattrass, C.; Nayak, T. K.; Nelson, J. M.; Netrakanti, P. K.; Nogach, L. V.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Okorokov, V.; Oldenburg, M.; Olson, D.; Pachr, M.; Pal, S. K.; Panebratsev, Y.; Panitkin, S. Y.; Pavlinov, A. I.; Pawlak, T.; Peitzmann, T.; Perevoztchikov, V.; Perkins, C.; Peryt, W.; Phatak, S. C.; Picha, R.; Planinic, M.; Pluta, J.; Poljak, N.; Porile, N.; Porter, J.; Poskanzer, A. M.; Potekhin, M.; Potrebenikova, E.; Potukuchi, B. V. K. S.; Prindle, D.; Pruneau, C.; Putschke, J.; Rakness, G.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Razin, S. V.; Reinnarth, J.; Relyea, D.; Retiere, F.; Ridiger, A.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Rose, A.; Roy, C.; Ruan, L.; Russcher, M. J.; Sahoo, R.; Sakuma, T.; Salur, S.; Sandweiss, J.; Sarsour, M.; Sazhin, P. S.; Schambach, J.; Scharenberg, R. P.; Schmitz, N.; Schweda, K.; Seger, J.; Selyuzhenkov, I.; Seyboth, P.; Shabetai, A.; Shahaliev, E.; Shao, M.; Sharma, M.; Shen, W. Q.; Shimanskiy, S. S.; Sichtermann, E.; Simon, F.; Singaraju, R. N.; Smirnov, N.; Snellings, R.; Sood, G.; Sorensen, P.; Sowinski, J.; Speltz, J.; Spinka, H. M.; Srivastava, B.; Stadnik, A.; Stanislaus, T. D. S.; Stock, R.; Stolpovsky, A.; Strikhanov, M.; Stringfellow, B.; Suaide, A. A. P.; Sugarbaker, E.; Sumbera, M.; Sun, Z.; Surrow, B.; Swanger, M.; Symons, T. J. M.; de Toledo, A. Szanto; Tai, A.; Takahashi, J.; Tang, A. H.; Tarnowsky, T.; Thein, D.; Thomas, J. H.; Timmins, A. R.; Timoshenko, S.; Tokarev, M.; Trainor, T. A.; Trentalange, S.; Tribble, Robert E.; Tsai, O. D.; Ulery, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van der Kolk, N.; van Leeuwen, M.; Vander Molen, A. M.; Varma, R.; Vasilevski, I. M.; Vasiliev, A. N.; Vernet, R.; Vigdor, S. E.

    2007-01-01

    We present strange particle spectra and yields measured at midrapidity in root s = 200 GeV proton-proton (p + p) collisions at the BNL Relativistic Heavy Ion Collider (RHIC). We find that the previously observed universal transverse mass (m...

  10. psi' production in Pb-Pb collisions at 158 GeV/nucleon

    E-Print Network [OSTI]

    NA50 Collaboration

    2006-12-08

    psi' production is studied in Pb-Pb collisions at 158 GeV/c per nucleon incident momentum. Absolute cross-sections are measured and production rates are investigated as a function of the centrality of the collision. The results are compared with those obtained for lighter colliding systems and also for the J/psi meson produced under identical conditions.

  11. 3 GeV Booster Synchrotron Conceptual Design Report

    SciTech Connect (OSTI)

    Wiedemann, Helmut

    2009-06-02

    Synchrotron light cna be produced from a relativistic particle beam circulating in a storage ring at extremely high intensity and brilliance over a large spectral region reaching from the far infrared regime to hard x-rays. The particles, either electrons or positrons, radiate as they are deflected in the fields of the storage ring bending magnets or of magnets specially optimized for the production of synchrotron light. The synchrotron light being very intense and well collimated in the forward direction has become a major tool in a large variety of research fields in physics, chemistry, material science, biology, and medicine.

  12. High-Speed Network Enables Industrial Internet | GE Global Research

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

    Infrastructure to Connect Machines, Data and People at Light Speed to the Industrial Internet Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new...

  13. Project#12: Zigang Ge and Todd McDevitt: SpatialTemporal Differentiation of Embryonic Stem Cells with Engineering Technologies and Molecular Biology Synergistically

    E-Print Network [OSTI]

    Weber, Rodney

    Project#12: Zigang Ge and Todd McDevitt: SpatialTemporal Differentiation of Embryonic Stem Cells is to incorporate "layerbylayer" technologies being developed by Dr. GE's lab with microspheremediated embryoid

  14. Chemical non-equilibrium and deconfinement in 200 A GeV Sulphur induced reactions

    E-Print Network [OSTI]

    Jean Letessier; Johann Rafelski

    1998-10-06

    We interpret hadronic particle abundances produced in S--Au/W/Pb 200 A GeV reactions in terms of the final state hadronic phase space model and determine by a data fit of the chemical hadron freeze-out parameters. Allowing for the flavor abundance non-equilibrium a highly significant fit to experimental particle abundance data emerges, which supports possibility of strangeness distillation. We find under different strategies stable values for freeze-out temperature T_f=143\\pm3 MeV, baryochemical potential \\mu_B= 173\\pm6 MeV, ratio of strangeness (\\gamma_s) and light quark (\\gamma_q) phase space occupancies \\gamma_s/\\gamma_q=0.60\\pm0.02, and \\gamma_q=1.22\\pm0.05 without accounting for collective expansion (radial flow). When introducing flow effects which allow a consistent description of the transverse mass particle spectra, yielding |v_c|=0.49\\pm0.01c, we find \\gamma_s/\\gamma_q=0.69\\pm0.03, \\gamma_q=1.41\\pm0.08. The strange quark fugacity is fitted at \\lambda_s=1.00\\pm0.02 suggesting chemical freeze-out directly from the deconfined phase.

  15. Study on the Ge{sub 1?x}Sn{sub x}/HfO{sub 2} interface and its impacts on Ge{sub 1?x}Sn{sub x} tunneling transistor

    SciTech Connect (OSTI)

    Qiu, Yingxin; Wang, Runsheng, E-mail: ruhuang@pku.edu.cn, E-mail: r.wang@pku.edu.cn; Huang, Qianqian; Huang, Ru, E-mail: ruhuang@pku.edu.cn, E-mail: r.wang@pku.edu.cn [Key Laboratory of Microelectronic Devices and Circuits, Institute of Microelectronics, Peking University, Beijing 100871 (China)

    2014-06-21

    In this paper, we employ first-principle calculation to investigate the Ge{sub 1?x}Sn{sub x}/HfO{sub 2} interface, and then evaluate its impacts on Ge{sub 1?x}Sn{sub x} tunneling field-effect transistor (TFET). First-principle calculations of Ge{sub 1?x}Sn{sub x}/HfO{sub 2} interfaces in the oxygen-rich process atmosphere indicate that the interface states originate from the Ge and Sn dangling bond, rather than Hf-bond. The total density of state shows that there are more interface states in the semiconductor bandgap with increasing Sn fraction. By further incorporating the material and interface parameters from density functional theory calculation into advanced device simulation, the electrical characteristics of Ge{sub 1?x}Sn{sub x} TFET are investigated. Removing the Sn atom from the first atom layer of Ge{sub 1?x}Sn{sub x} in device processes is found to be beneficial to reduce the degradations. For the degradation mechanisms, the trap-assisted-tunneling is the dominant mechanism at the low Sn fraction, and enhanced Shockley-Read-Hall recombination induced by traps becomes the dominant mechanism with increasing Sn fraction. The results are helpful for the interface optimization of Ge{sub 1?x}Sn{sub x} TFET.

  16. Z:\\Gerontology\\Program\\Application Packages\\PBD Application Package\\PBD package 2008\\Reference form.doc de partme nt of ge rontology

    E-Print Network [OSTI]

    .doc de partme nt of ge rontology gerontology research centre Letter of ReferenceLetter of Reference

  17. Z:\\Gerontology\\Program\\Application Packages\\MA Application Package\\Application Package 2008\\Reference Form.doc de partme nt of ge rontology

    E-Print Network [OSTI]

    \\Reference Form.doc de partme nt of ge rontology gerontology research centre LETTER OF REFERENCE MASTER

  18. ECS2003_#923_Fitzgerald ECS Meeting Proceedings, Paris, France April 29, 2003 MOSFET CHANNEL ENGINEERING USING STRAINED SI, SIGE, AND GE

    E-Print Network [OSTI]

    ENGINEERING USING STRAINED SI, SIGE, AND GE CHANNELS E.A. Fitzgerald,1 M.L. Lee,1 C.W. Leitz,1 and D MOSFET channel designs in the SiGe/Relaxed SiGe/Si system to explore the limits of electron and hole. The largest improvement in both PMOS and NMOS drive current enhancements were achieved with a -Si/-Ge

  19. Strained Ge channel p-type metaloxidesemiconductor field-effect transistors grown on Si1xGex Si virtual substrates

    E-Print Network [OSTI]

    Strained Ge channel p-type metal­oxide­semiconductor field-effect transistors grown on Si1ÀxGex ÕSi 2001; accepted for publication 29 August 2001 We have fabricated strained Ge channel p-type metal­oxide­semiconductor field-effect transistors (p-MOSFETs) on Si0.3Ge0.7 virtual substrates. The poor interface between

  20. GE Healthcare Life Sciences provides products and services used as tools for biopharmaceutical manufacturing, drug discovery and the latest in cellular technologies, thereby enabling our customers

    E-Print Network [OSTI]

    Uppsala Universitet

    GE Healthcare Life Sciences provides products and services used as tools for biopharmaceutical protein purification at Protein Tools, GE Healthcare, Uppsala Background Immobilized metal affinity independently and in collaborations. The master thesis will be carried out at GE Healthcare in Uppsala and last