National Library of Energy BETA

Sample records for office atlanta ga

  1. IEEE Energy2030 Atlanta, GA USA

    E-Print Network [OSTI]

    Gross, George

    of an aggregation of battery vehicles for the provision of frequency regulation ­ requiring very fast response timesIEEE Energy2030 Atlanta, GA USA 17-18 November, 2008 Design of a Conceptual Framework for the V2G in common is the batteries, which provide good storage capacity that can be effectively integrated

  2. 495 Tech Way NW Atlanta, GA 30318

    E-Print Network [OSTI]

    Li, Mo

    495 Tech Way NW Atlanta, GA 30318 404.385.0384 comments@energy.gatech.edu Copyright 2014 · Georgia concerns, low-cost, clean, secure energy solutions will be necessary to address our global energy needs and sustain our way of life. Georgia Tech Energy Innovations The Strategic Energy Institute's scientists

  3. Istanbul,Turkey & Atlanta, GA Istanbul,Turkey

    E-Print Network [OSTI]

    Frantz, Kyle J.

    Istanbul,Turkey & Atlanta, GA Istanbul,Turkey & Atlanta, GA 2012 Media, Journalism and Business for departure to Istanbul,Turkey Day 9 Depart for Istanbul; guided cultural visit upon arrival; group dinner Day business leaders; site visits to local universities Day 18 UPS and the value of logistics inTurkey Day 19

  4. INFORMS `03, Atlanta GA, October 19-21 A Supply Chain Network EconomyA Supply Chain Network Economy

    E-Print Network [OSTI]

    Nagurney, Anna

    INFORMS `03, Atlanta GA, October 19-21 A Supply Chain Network EconomyA Supply Chain Network Economy, GA, October 19-22, 2003 Supply Chain EconomySupply Chain Economy Supply Chain Economy (SCE a supply chain economy ­ Comprising heterogeneous supply chains ­ Involving in production, distribution

  5. In Proceedings of the 1999 IEEE/ASME International Conference on Advanced Intelligent Mechatronics, Atlanta, GA. Abstract Advanced mechatronic systems increasingly are

    E-Print Network [OSTI]

    In Proceedings of the 1999 IEEE/ASME International Conference on Advanced Intelligent Mechatronics, Atlanta, GA. Abstract ­ Advanced mechatronic systems increasingly are finding application in modern to be coordinated as an aggregate mechatronic system. One important consideration in mechatronics design

  6. Timothy J. Bartness Departments of Biology and Center for Behavioral Neuroscience, Georgia State University, Atlanta, GA 30303. Gregory E. Demas Department of Biology and Program in Neural

    E-Print Network [OSTI]

    Demas, Greg

    University, Atlanta, GA 30303. Gregory E. Demas Department of Biology and Program in Neural Science, Indiana University, Bloomington, IN 47405. Neurobiology of Food and Fluid Intake, 2nd Ed., Volume 14 of Handbook, and from humans, many or most of the fundamental problems in ingestive behavior 423 #12;have not been

  7. Secretary Moniz's Keynote at the Sam Nunn Policy Forum in Atlanta, GA --

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

    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 Natural GasAdjustmentsShirley Ann JacksonDepartment ofOffice|inWestMay 13,Discuss theDepartment of EnergyMarissaAs

  8. Advancing Residential Retrofits in Atlanta

    SciTech Connect (OSTI)

    Jackson, Roderick K; Kim, Eyu-Jin; Roberts, Sydney; Stephenson, Robert

    2012-07-01

    This report will summarize the home energy improvements performed in the Atlanta, GA area. In total, nine homes were retrofitted with eight of the homes having predicted source energy savings of approximately 30% or greater based on simulated energy consumption.

  9. Atlanta- Sustainable Development Design Standards

    Broader source: Energy.gov [DOE]

    In December 2003, the City of Atlanta passed a green building [http://www.atlantaga.gov/modules/showdocument.aspx?documentid=547 ordinance] that applies to city-owned facilities and city-funded...

  10. Building America Case Study: Ground Source Heat Pump Research, TaC Studios Residence, Atlanta, Georigia (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-09-01

    As part of the NAHB Research Center Industry Partnership, Southface partnered with TaC Studios, an Atlanta based architecture firm specializing in residential and light commercial design, on the construction of a new test home in Atlanta, GA in the mixed-humid climate. This home serves as a residence and home office for the firm's owners, as well as a demonstration of their design approach to potential and current clients. Southface believes the home demonstrates current best practices for the mixed-humid climate, including a building envelope featuring advanced air sealing details and low density spray foam insulation, glazing that exceeds ENERGY STAR requirements, and a high performance heating and cooling system. Construction quality and execution was a high priority for TaC Studios and was ensured by a third party review process. Post construction testing showed that the project met stated goals for envelope performance, an air infiltration rate of 2.15 ACH50. The homeowner's wished to further validate whole house energy savings through the project's involvement with Building America and this long-term monitoring effort. As a Building America test home, this home was evaluated to detail whole house energy use, end use loads, and the efficiency and operation of the ground source heat pump and associated systems. Given that the home includes many non-typical end use loads including a home office, pool, landscape water feature, and other luxury features not accounted for in Building America modeling tools, these end uses were separately monitored to determine their impact on overall energy consumption.

  11. Engineering vertically aligned InAs/GaAs quantum dot structures via anion exchange

    E-Print Network [OSTI]

    Wang, Zhong L.

    of Technology, Atlanta, GA 30332-0245, USA b School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA Received 17 March 2002; accepted 16 April 2002 by D. Van Dyck Abstract P exchange; D. Stranski­Krastanov (S­K) growth Self-assemble by exploiting the Stranski­Krastanov (S

  12. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    IL (United States) Atlanta Regional Office, Atlanta, GA (United States) Atmospheric System Research Bartlesville Project Office, OK (United States) Battelle Memorial...

  13. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Photon Source, Argonne, IL (United States) Atlanta Regional Office, Atlanta, GA (United States) Atmospheric System Research Bartlesville Project Office, OK (United...

  14. Will A. Overholt 388 Oakland Ave SE, Atlanta, GA 30312

    E-Print Network [OSTI]

    Storici, Francesca

    sequences for oil-degrading bacterial strains from beach sands impacted by the Deepwater Horizon oil spill in Gulf of Mexico Beach Sands Impacted by the Deepwater Horizon Oil Spill. Applied and Environmental the metabolic potential of indigenous microbial communities with the degradation of oil-hydrocarbons in deep sea

  15. Vehicle Technologies Office Merit Review 2015: Advanced Low-Cost SiC and GaN Wide Bandgap Inverters for Under-the-Hood Electric Vehicle Traction Drives

    Broader source: Energy.gov [DOE]

    Presentation given by APEI Inc. at 2015 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about advanced low-cost SiC and GaN wide...

  16. Vehicle Technologies Office Merit Review 2014: Advanced Low-Cost SiC and GaN Wide Bandgap Inverters for Under-the-Hood Electric Vehicle Traction Drives

    Broader source: Energy.gov [DOE]

    Presentation given by APEI Inc. at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about Advanced low-cost SIC and GaN wide...

  17. Atlanta Chemical Engineering LLC | 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 JEnvironmental Jump to:EAandAmminex A SOpenAshley, Ohio:Atchison-HoltAtlanta Chemical Engineering

  18. Atlanta, Georgia: Energy Resources | 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 JEnvironmental Jump to:EAandAmminex A SOpenAshley, Ohio:Atchison-HoltAtlanta Chemical

  19. Energy Management Program at Atlanta Postal Service Distribution Center 

    E-Print Network [OSTI]

    Brown, M.; Ansari, A.

    2001-01-01

    of standard operating procedures, energy monitoring, and team-based problem solving. Implementation activity at the Atlanta Bulk Mail Facility has included a gap analysis, selection of an implementation team, and initial training. During the first quarter...

  20. OFFICE,

    Office of Legacy Management (LM)

    OFFICE, . . . . . ..-... --.-... .-..I... ..-... bUmME. wArl&l ' rrsldu*. in the dw6lopmQt pmgrwh : Be ostiamts Uuat not man lf+ .b%'o,Qds. cik'e%ah of the...

  1. Georgia and Arkansas Residential Energy Code Field Studies |...

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

    GA Partners: - Advanced Energy - Raleigh, NC - Arkansas Economic Development Commission, Energy Office - Little Rock, AR - Georgia Department of Community Affairs - Atlanta, GA -...

  2. Alternative Fuels Data Center: Atlanta Airport Converts Shuttles to CNG

    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 B L O O D S TA I NLoans The Oregon DepartmentAtlanta Airport

  3. North Atlanta, Georgia: Energy Resources | 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:QAsource History ViewMayo, Maryland:NPI VenturesNew Hampshire: EnergyReservoir |Solkraft AS JumpAndrewsAtlanta,

  4. Workplace Charging Challenge Partner: City of Atlanta | Department of

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

    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 Natural GasAdjustmentsShirley Ann JacksonDepartment| Department of EnergyDataWind TheEnergyEnergy Atlanta The

  5. DOE ZERH Case Study: Heirloom Design Build, Euclid Avenue, Atlanta, GA

    SciTech Connect (OSTI)

    none,

    2015-09-01

    Case study of a DOE 2015 Housing Innovation Award winning custom home in the mixed-humid climate that got a HERS 50 without PV, with 2x6 16” on center walls with R-19 ocsf; basement with R-28 ccsf, R-5 rigid foam under slab; sealed attic with R-28 ocsf under roof deck; 22.8 SEER; 12.5 HSPF heat pump.

  6. Secretary Moniz's Keynote at the Sam Nunn Policy Forum in Atlanta, GA --

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

    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 Delicious RankADVANCED MANUFACTURINGEnergy BillsNo.Hydrogen4 » Searchwith First James R. SchlesingerAs Delivered |

  7. Remarks by Federal Blue Ribbon Commission J. David Jameson Atlanta, GA

    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 wouldMassR&D100 Winners *Reindustrialization Reindustrialization AsInnovation Portal

  8. HIA 2015 DOE Zero Energy Ready Home Case Study: Heirloom Design Build, Euclid Avenue, Atlanta, GA

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

    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 Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing Programs |Reference StationFranklinHammer and Hand

  9. DeKalb County/Metropolitan Atlanta Alternative Fuel and Advanced...

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

    60tifrancis2012o.pdf More Documents & Publications DeKalb CountyMetropolitan Atlanta Alternative Fuel and Advanced Technology Vehicle Project DeKalb CountyMetropolitan...

  10. DeKalb County/Metropolitan Atlanta Alternative Fuel and Advanced...

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

    vt060francis2010p.pdf More Documents & Publications DeKalb CountyMetropolitan Atlanta Alternative Fuel and Advanced Technology Vehicle Project DeKalb CountyMetropolitan...

  11. DeKalb County/Metropolitan Atlanta Alternative Fuel and Advanced...

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

    60tifrancis2011p.pdf More Documents & Publications DeKalb CountyMetropolitan Atlanta Alternative Fuel and Advanced Technology Vehicle Project DeKalb CountyMetropolitan...

  12. Community transportation : alternative transportation provision in a low-income neighborhoods in southeast Atlanta

    E-Print Network [OSTI]

    Alexander, James W., 1977-

    2004-01-01

    Regional transit agencies are ineffective at meeting many of the basic transportation needs of a clustered "Study Area" of low-income Atlanta neighborhoods. For transit dependant residents in the Study Area, getting to the ...

  13. Human Resources Payroll and Employee Benefits Office 108 Pearman Boulevard at Old Stadium Road

    E-Print Network [OSTI]

    Stuart, Steven J.

    Clemson, SC 29631 Atlanta, GA 30328-6104 864-654-5556 800-842-2003 X3524 800-755-7649 www.tiaa-cref.org/scorp 29670 864-654-3121 864-261-9674 Plan #: SCORP CU 1013145-01 For additional information or assistance

  14. Economic evaluation of the Annual Cycle Energy System. Volume I. Executive summary. Final report. [In Minneapolis, Atlanta, and Philadelphia

    SciTech Connect (OSTI)

    Not Available

    1980-05-01

    The objective of this study is to determine the energy effectiveness and the economic viability of the ACES concept. Three different classes of building are investigated, namely: single-family residence; multi-family residence; and commercial office building. The application of ACES to each of these building types is studied in three different climatic regions: Minneapolis, Atlanta, and Philadelphia. Computer programs - ACESIM for the residences and CACESS for the office building - were used, each comprised of four modules: loads; design; simulation; and economic. For each building type in each geographic location, the economic evaluation of the ACES is based on a comparison of the present worth of the ACES to the present worth of a number of conventional systems. The results of this analysis indicate that the economic viability of the ACES is very sensitive to the assumed value of the property tax, maintenace cost, and fuel-escalation rates, while it is relatively insensitive to the assumed values of other parameters. Fortunately, any conceivable change in the fuel-escalation rates would tend to increase the viability of the ACES concept. An increase in the assumed value of the maintenance cost or property tax would tend to make the ACES concept less viable; a decrease in either would tend to make the ACES concept more viable. The detailed results of this analysis are given in Section 5.4 of Volume II. 2 figures, 21 tables.

  15. Summary of Needs and Opportunities from the 2011 Residential Energy Efficiency Stakeholders Meeting: Atlanta, Georgia -- March 16-18, 2011

    SciTech Connect (OSTI)

    Not Available

    2011-05-01

    This summary report outlines needs and issues for increasing energy efficiency of new and existing U.S homes, as identified at the U.S Department of Energy Building America program Spring 2011 stakeholder meeting in Atlanta, Georgia.

  16. Aero-Structural Design Investigations for Biplane Wind Turbine Blades

    E-Print Network [OSTI]

    Roth-Johnson, Perry

    2014-01-01

    Turbine Blades,” in AWEA Windpower, (Atlanta, GA), pp. 1–22,turbine blades,” AWEA Windpower, Atlanta, GA, (presentation)

  17. Badge Office

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

    Badge Office Badge Office The central point where badges are issued to employees and official visitors. Contact Badge Office (505) 667-6901 Email Badge Office location As the...

  18. 15th Symposium on Meteorological Observations and Instrumentation, AMS, Atlanta, 2010 RECENT RESEARCH ON METEOROLOGICAL OBSERVATIONS AND INSTRUMENTATION AT

    E-Print Network [OSTI]

    Wauben, Wiel

    15th Symposium on Meteorological Observations and Instrumentation, AMS, Atlanta, 2010 1 RECENT RESEARCH ON METEOROLOGICAL OBSERVATIONS AND INSTRUMENTATION AT KNMI Hannelore Bloemink, Marijn de Haij are generated at about 30 locations in the meteorological network and are centrally available every 10 minutes

  19. Preprint: Centennial Meeting of the American Physical Society Meeting, Atlanta, 1999, to be published in Computer Physics Communication

    E-Print Network [OSTI]

    Heermann, Dieter W.

    Preprint: Centennial Meeting of the American Physical Society Meeting, Atlanta, 1999, to be published in Computer Physics Communication Teaching Physics in the Virtual University: The Mechanics and some basic physical objects implemented as Java classes. Students can extend these classes in order

  20. Atlanta Survey

    Gasoline and Diesel Fuel Update (EIA)

    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 Natural GasAdjustments (Billion Cubic Feet) Wyoming963 1.969 1.979Coal4 Arizona - NaturalYear JanProfile of Motor-Vehicle

  1. Comparison of nonmethane organic compound concentration data collected by two methods in Atlanta

    SciTech Connect (OSTI)

    Shreffler, J.H.

    1993-12-01

    Title I of the Clean Air Act Amendments of 1990 calls for 'enhanced monitoring' of ozone, which is planned to include measurements of atmospheric non-methane organic compounds (NMOCs). NMOC concentration data gathered by two methods in Atlanta, Georgia during July and August 1990 are compared in order to assess the reliability of such measurements in an operational setting. During that period, automated gas chromatography (GC) systems (Field systems) were used to collect NMOC continuously as one-hour averages. In addition, canister samples of ambient air were collected on an intermittent schedule for quality control purposes and analyzed by laboratory GC (the Lab system). Data from the six-site network included concentrations of nitrogen oxides (NOx), carbon monoxide (CO), ozone, total NMOC (TNMOVC), and 47 identified NMOCs. (Copyright (c) 1993-Air Waste Management Association.)

  2. ARCS Additional FirstYear PhD Student Award The Atlanta chapter of ARCS has just informed me that they will honor us with another graduate student

    E-Print Network [OSTI]

    Arnold, Jonathan

    ARCS Additional FirstYear PhD Student Award The Atlanta chapter of ARCS has just informed me meets their definition listed above. Sincerely, Harry A. Dailey, Ph.D. Professor and Director

  3. Campus Sustainability Office Campus Planning Office

    E-Print Network [OSTI]

    Elzanowski, Marek

    Campus Sustainability Office (CSO) Campus Planning Office (CPO) Campus Sustainability Manager (Molly Bressers) Campus Sustainability Office and Campus Planning Office May 2015 Student Employee (Thea

  4. CMTA Office

    High Performance Buildings Database

    Prospect, KY When CMTA outgrew their old office space, the consultant engineering company decided to construct a new building. Not only does the structure provide offices for the firm, it also showcases progressive design elements and allows the firm to test new technologies and demonstrate their effectiveness to clients. The new CMTA office building is located in a live-work development on the outskirts of Louisville, KY. The location was selected to place the office close to where the employees live.

  5. President Office Vice President Office

    E-Print Network [OSTI]

    Wu, Yih-Min

    Affairs Division Computer Information Management Division Media Instruction and Production Center Division Campus Security Supplies Office Office of Research and Development Planning Section and Waste Control Division Radiation Protection Division Biological Pollution Control Division #12

  6. Building Technologies Office Overview

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

    Roland Risser Director, Building Technologies Office Building Technologies Office Energy Efficiency Starts Here. 2 Building Technologies Office Integrated Approach: Improving...

  7. AlGaN/GaN-based power semiconductor switches

    E-Print Network [OSTI]

    Lu, Bin, Ph. D. Massachusetts Institute of Technology

    2013-01-01

    AlGaN/GaN-based high-electron-mobility transistors (HEMTs) have great potential for their use as high efficiency and high speed power semiconductor switches, thanks to their high breakdown electric field, mobility and ...

  8. Sustainability Performance Office | Department of Energy

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

    Sustainability Performance Office Sustainability Performance Office Sustainability Performance Office Sustainability Performance Office Sustainability Performance Office...

  9. Eleventh ARM Science Team Meeting Proceedings, Atlanta, Georgia, March 19-23, 2001 Radar-based Retrievals of Cloud Properties in the Arctic

    E-Print Network [OSTI]

    Shupe, Matthew

    Eleventh ARM Science Team Meeting Proceedings, Atlanta, Georgia, March 19-23, 2001 1 Radar Radiation Measurement (ARM) program Cloud and Radiation Testbed (CART) sites, all techniques discussed here can be applied to measurements taken at the different ARM sites. Briefly summarized here

  10. Building Technologies Office Overview

    SciTech Connect (OSTI)

    2013-04-01

    Building Technologies Office Overview Presentation for the 2013 Building Technologies Office's Program Peer Review

  11. Southface Energy Institute: Advanced Commercial Buildings Initiative...

    Energy Savers [EERE]

    Fund - Atlanta, GA - Oak Ridge National Laboratory - Oak Ridge, TN - Acuity Brands Lighting - Atlanta, GA - Vermont Energy Investment Corp - Burlington, VT - Georgia Power-...

  12. Review of Multi-Person Exposure Calls to a Regional Poison Control Center

    E-Print Network [OSTI]

    Morgan, Brent W; Skinner, Carl G; Kleiman, Richard J; Geller, Robert J; Chang, Arthur S

    2010-01-01

    Exposure Calls to a Regional Poison Control Center Brent W.Medicine and the Georgia Poison Center, Atlanta, GA †of Pediatrics and the Georgia Poison Center, Atlanta, GA

  13. Strategic Utilization of Paper/Wood Waste for Biodiesel Fuel Art J. Ragauskas, Institute of Paper Science and Technology; Georgia Institute of Technology, Atlanta, GA.

    E-Print Network [OSTI]

    Strategic Utilization of Paper/Wood Waste for Biodiesel Fuel Art J. Ragauskas, Institute of Paper lignocellulosics to biodiesel fuel Feedstocks ABSTRACT This poster examines the potential of utilizing waste paper

  14. Office of Chief Financial Officer

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2001-01-19

    This Order implements the provisions of the Chief Financial Officers Act of 1990 within the Department of Energy. Cancels SEN 34-91. Canceled by DOE O 520.1A.

  15. Urban airshed modeling of air quality impacts of alternative transportation fuel use in Los Angeles and Atlanta

    SciTech Connect (OSTI)

    NONE

    1997-12-01

    The main objective of NREL in supporting this study is to determine the relative air quality impact of the use of compressed natural gas (CNG) as an alternative transportation fuel when compared to low Reid vapor pressure (RVP) gasoline and reformulated gasoline (RFG). A table lists the criteria, air toxic, and greenhouse gas pollutants for which emissions were estimated for the alternative fuel scenarios. Air quality impacts were then estimated by performing photochemical modeling of the alternative fuel scenarios using the Urban Airshed Model Version 6.21 and the Carbon Bond Mechanism Version IV (CBM-IV) (Geary et al., 1988) Using this model, the authors examined the formation and transport of ozone under alternative fuel strategies for motor vehicle transportation sources for the year 2007. Photochemical modeling was performed for modeling domains in Los Angeles, California, and Atlanta, Georgia.

  16. Fellows' Officers

    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 Racah861May 2011AprilOfficers Fellows' Officers

  17. Energy Secretary Moniz to Keynote Sam Nunn Policy Forum in Atlanta |

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

    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 Natural GasAdjustmentsShirley Ann JacksonDepartment ofOffice ofofWind ProjectsEfficiency CompetitionEfficientDepartment of

  18. Responsible University Officer Chief Information Officer

    E-Print Network [OSTI]

    Whitton, Mary C.

    Responsible University Officer Chief Information Officer Responsible Office Information Technology Services Information Security Liaison Policy Policy Statement Given the risks associated with information and Department Heads be aware of information security issues and of their responsibilities for mitigating

  19. Office of Chief Financial Officer

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2001-11-27

    Page Change 1 to DOE O 520.1 modifies the responsibility statement to include NNSA Field CFO positions, modifies Heads of Field Elements responsibilities for consistency with the CFO responsibilities, and makes a minor change to reflect the establishment of the Office of Management, Budget and Evaluation. Cancels SEN 34-9.

  20. Responsible University Officer Chief Information Officer

    E-Print Network [OSTI]

    Whitton, Mary C.

    Responsible University Officer Chief Information Officer Responsible Office Information Technology at Chapel Hill that manages its own or subcontracts its information technology must: Establish and maintain Management Plan, contact the Information Security Office (ISO) at 919-445-9393 or security@unc.edu. Designate

  1. OFFICE of the CHIEF INFORMATION SECURITY OFFICER

    E-Print Network [OSTI]

    Matrajt, Graciela

    OFFICE of the CHIEF INFORMATION SECURITY OFFICER 2013 Information Security and Privacy Annual conversation,The Office of the Chief Information Security Officer (CISO) invites readers to email ciso@uw.edu by May 1st, 2014 with privacy-themed cap- tions for the cartoon on the right.Winning captions

  2. Director's Office

    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 HAB PacketDiesel pricesCenter at CornellDirector's Office Print

  3. Office Buildings

    U.S. Energy Information Administration (EIA) Indexed Site

    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 PageMonthly","10/2015"4,"Ames5 Tables July 1996 Energy Information Administration Office of Coal, Nuclear,DecadeYear Jan FebElements)Feet) Decade8 45YearYear

  4. Polarization-engineered GaN/InGaN/GaN tunnel diodes

    SciTech Connect (OSTI)

    Krishnamoorthy, Sriram; Nath, Digbijoy N.; Akyol, Fatih; Park, Pil Sung; Esposto, Michele; Rajan, Siddharth [Department of Electrical and Computer Engineering, Ohio State University, Columbus, Ohio 43210 (United States)

    2010-11-15

    We report on the design and demonstration of polarization-engineered GaN/InGaN/GaN tunnel junction diodes with high current density and low tunneling turn-on voltage. Wentzel-Kramers-Brillouin calculations were used to model and design tunnel junctions with narrow band gap InGaN-based barrier layers. N-polar p-GaN/In{sub 0.33}Ga{sub 0.67}N/n-GaN heterostructure tunnel diodes were grown using molecular beam epitaxy. Efficient interband tunneling was achieved close to zero bias with a high current density of 118 A/cm{sup 2} at a reverse bias of 1 V, reaching a maximum current density up to 9.2 kA/cm{sup 2}. These results represent the highest current density reported in III-nitride tunnel junctions and demonstrate the potential of III-nitride tunnel devices for a broad range of optoelectronic and electronic applications.

  5. High School Students’ Perceptions of Motivations for Cyberbullying: An Exploratory Study

    E-Print Network [OSTI]

    Varjas, Kris; Talley, Jasmaine; Meyers, Joel; Parris, Leandra; Cutts, Hayley

    2010-01-01

    Climate, and Classroom Management, Atlanta, GA SupervisingCyberbullying and Classroom Management and the Educational

  6. GaInNAs laser gain

    SciTech Connect (OSTI)

    CHOW,WENG W.; JONES,ERIC D.; MODINE,NORMAND A.; KURTZ,STEVEN R.; ALLERMAN,ANDREW A.

    2000-05-23

    The optical gain spectra for GaInNAs/GaAs quantum wells are computed using a microscopic laser theory. From these spectra, the peak gain and carrier radiative decay rate as functions of carrier density are determined. These dependences allow the study of the lasing threshold current density of GaInNAs/GaAs quantum well structures.

  7. Office of Communication - Speakers' Bureau

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

    Office of Communication Office of Communication home | Office of Communication staff | speakers' bureau | available materials | links | talk to Fermilab Speakers' Bureau The Office...

  8. Advantages of the Blue InGaN/GaN Light-Emitting Diodes with an AlGaN/GaN/AlGaN Quantum Well Structured Electron Blocking Layer

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    ABSTRACT: InGaN/GaN light-emitting diodes (LEDs) with p-(AlGaN/GaN/AlGaN) quantum well structured electron. The proposed QWEBL LED structure, in which a p-GaN QW layer is inserted in the p-AlGaN electron blocking layer the radiative recombination rates across the active region. Consequently, the light output power was enhanced

  9. Office of International Education International Student, Scholar, and Immigration Services (ISSIS)

    E-Print Network [OSTI]

    Arnold, Jonathan

    1 Rev. 11-11 Office of International Education International Student, Scholar, and Immigration Services (ISSIS) 1324 S. Lumpkin Street, Athens, GA 30602-5407 issis@uga.edu (706) 542-2900 fax: (706) 583 remain in status while in the U.S.: · Check-in with the Office of International Education (OIE

  10. Red emitting photonic devices using InGaP/InGaAlP material system

    E-Print Network [OSTI]

    Kangude, Yamini

    2005-01-01

    In this thesis, two red emitting photonic devices are presented using the InGaP/InGaAlP material system. InGaP/InGaAlP material system provides large flexibility in the band gap energy while being lattice matched to GaAs ...

  11. Finance & Administration Controller's Office

    E-Print Network [OSTI]

    Weston, Ken

    Finance & Administration Controller's Office April 2014 Michael Williams Controller Controller ICOFA 61318 Revised: 4/4/2014 #12;Finance & Administration Controller's Office Accounting & Asset Coordinator Property Surplus Sales 81269 Revised: 4/4/2014 #12;Finance & Administration Controller's Office

  12. Chief Information Officer

    Broader source: Energy.gov [DOE]

    The Federal Energy Regulatory Commission is looking for an experienced senior level executive to serve as the Chief Information Officer (CIO). The Chief Information Officer (CIO) reports directly...

  13. Building Technologies Office Overview

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

    Roland Risser Director, Building Technologies Office Building Technologies Office Overview Our Homes and Buildings Use 40% of Our Nation's Energy and 75% of Electricity Energy Use...

  14. Building Technologies Office Overview

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

    Technologies Office Roland Risser Director, Building Technologies Office National Energy Consumption 40% 60% Reducing consumption or improving performance calls for cutting-edge...

  15. GaAs, AlGaAs and InGaP Tunnel Junctions for Multi-Junction Solar Cells Under Concentration: Resistance Study

    SciTech Connect (OSTI)

    Wheeldon, Jeffrey F.; Valdivia, Christopher E.; Walker, Alex; Kolhatkar, Gitanja; Hall, Trevor J.; Hinzer, Karin; Masson, Denis; Riel, Bruno; Fafard, Simon; Jaouad, Abdelatif; Turala, Artur; Ares, Richard; Aimez, Vincent

    2010-10-14

    The following four TJ designs, AlGaAs/AlGaAs, GaAs/GaAs, AlGaAs/InGaP and AlGaAs/GaAs are studied to determine minimum doping concentration to achieve a resistance of <10{sup -4} {omega}{center_dot}cm{sup 2} and a peak tunneling current suitable for MJ solar cells up to 1500-suns concentration (operating current of 21 A/cm{sup 2}). Experimentally calibrated numerical models are used to determine how the resistance changes as a function of doping concentration. The AlGaAs/GaAs TJ design is determined to require the least doping concentration to achieve the specified resistance and peak tunneling current, followed by the GaAs/GaAs, and AlGaAs/AlGaAs TJ designs. The AlGaAs/InGaP TJ design can only achieve resistances >5x10{sup -4} {omega}cm{sup 2}.

  16. Advanced Manufacturing Office News

    SciTech Connect (OSTI)

    2013-08-08

    News stories about advanced manufacturing, events, and office accomplishments. Subscribe to receive updates.

  17. GaAs MOEMS Technology

    SciTech Connect (OSTI)

    SPAHN, OLGA B.; GROSSETETE, GRANT D.; CICH, MICHAEL J.; TIGGES, CHRIS P.; RENO, JOHN L.; PEAKE, GREGORY M.; KLEM, JOHN F.; LEAN, JEN; FULLER, CHARLES T.; BURKHART, JEFF; BAUER, THOMAS; SULLIVAN, CHARLES T.

    2003-03-01

    Many MEMS-based components require optical monitoring techniques using optoelectronic devices for converting mechanical position information into useful electronic signals. While the constituent piece-parts of such hybrid opto-MEMS components can be separately optimized, the resulting component performance, size, ruggedness and cost are substantially compromised due to assembly and packaging limitations. GaAs MOEMS offers the possibility of monolithically integrating high-performance optoelectronics with simple mechanical structures built in very low-stress epitaxial layers with a resulting component performance determined only by GaAs microfabrication technology limitations. GaAs MOEMS implicitly integrates the capability for radiation-hardened optical communications into the MEMS sensor or actuator component, a vital step towards rugged integrated autonomous microsystems that sense, act, and communicate. This project establishes a new foundational technology that monolithically combines GaAs optoelectronics with simple mechanics. Critical process issues addressed include selectivity, electrochemical characteristics, and anisotropy of the release chemistry, and post-release drying and coating processes. Several types of devices incorporating this novel technology are demonstrated.

  18. Intense terahertz emission from molecular beam epitaxy-grown GaAs/GaSb(001)

    SciTech Connect (OSTI)

    Sadia, Cyril P.; Laganapan, Aleena Maria; Agatha Tumanguil, Mae; Estacio, Elmer; Somintac, Armando; Salvador, Arnel; Que, Christopher T.; Yamamoto, Kohji; Tani, Masahiko

    2012-12-15

    Intense terahertz (THz) electromagnetic wave emission was observed in undoped GaAs thin films deposited on (100) n-GaSb substrates via molecular beam epitaxy. GaAs/n-GaSb heterostructures were found to be viable THz sources having signal amplitude 75% that of bulk p-InAs. The GaAs films were grown by interruption method during the growth initiation and using various metamorphic buffer layers. Reciprocal space maps revealed that the GaAs epilayers are tensile relaxed. Defects at the i-GaAs/n-GaSb interface were confirmed by scanning electron microscope images. Band calculations were performed to infer the depletion region and electric field at the i-GaAs/n-GaSb and the air-GaAs interfaces. However, the resulting band calculations were found to be insufficient to explain the THz emission. The enhanced THz emission is currently attributed to a piezoelectric field induced by incoherent strain and defects.

  19. Computational analysis of thin film InGaAs/GaAs quantum well solar cells with

    E-Print Network [OSTI]

    Yu, Edward T.

    Computational analysis of thin film InGaAs/GaAs quantum well solar cells with back side light, Austin, TX 78758, USA * ety@ece.utexas.edu Abstract: Simulations of thin film (~2.5 µm thick) InGaAs/GaAs. Roberts, G. Hill, and C. Calder, "Progress in quantum well solar cells," Thin Solid Films 511­512, 76

  20. GaSb/GaAs type II quantum dot solar cells for enhanced infrared spectral response

    E-Print Network [OSTI]

    Jalali. Bahram

    into existing multijunction cells either as a means to increase the current or efficiency by using low band gapGaSb/GaAs type II quantum dot solar cells for enhanced infrared spectral response R. B infrared spectral response of GaAs-based solar cells that incorporate type II GaSb quantum dots QDs formed

  1. The Office of Independent Enterprise Assessments' Office of Enforcemen...

    Office of Environmental Management (EM)

    The Office of Independent Enterprise Assessments' Office of Enforcement convened the 2014 DOE Safety and Security Enforcement Workshop May 13 and 14, 2014 The Office of Independent...

  2. Office of Personnel Management (OPM) Billing System PIA, Office...

    Energy Savers [EERE]

    Personnel Management (OPM) Billing System PIA, Office of Health, Safety and Security Office of Personnel Management (OPM) Billing System PIA, Office of Health, Safety and Security...

  3. USD E'16 ATLANTA

    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 ofDidDevelopmentat LENA| ReactionSite Map SiteUS ITER Jobs

  4. New GaInP/GaAs/GaInAs, Triple-Bandgap, Tandem Solar Cell for High-Efficiency Terrestrial Concentrator Systems

    SciTech Connect (OSTI)

    Kurtz, S.; Wanlass, M.; Kramer, C.; Young, M.; Geisz, J.; Ward, S.; Duda, A.; Moriarty, T.; Carapella, J.; Ahrenkiel, P.; Emery. K.; Jones, K.; Romero, M.; Kibbler, A.; Olson, J.; Friedman, D.; McMahon, W.; Ptak, A.

    2005-11-01

    GaInP/GaAs/GaInAs three-junction cells are grown in an inverted configuration on GaAs, allowing high quality growth of the lattice matched GaInP and GaAs layers before a grade is used for the 1-eV GaInAs layer. Using this approach an efficiency of 37.9% was demonstrated.

  5. Office of Information Management

    Broader source: Energy.gov [DOE]

    The Office of Information Management provides a broad range of information technology services in support of the Associate Under Secretary for the Office of Environment, Health, Safety and Security (AU).

  6. Office Buildings: Consumption Tables

    U.S. Energy Information Administration (EIA) Indexed Site

    and Type of Office Building Total (trillion Btu) per Building (million Btu) per Square Foot (thousand Btu) Dollars per Million Btu All Office Buildings 1,089 1,475 90.5 16.32...

  7. Finance & Administration Controller's Office

    E-Print Network [OSTI]

    McQuade, D. Tyler

    Finance & Administration Controller's Office July 2014 Michael Williams Controller Controller Administrative Services 51111 Catherine Hebert Program Director ICOFA 61318 Revised: 7/28/2014 #12;Finance Surplus Property 81269 Revised: 7/28/2014 #12;Finance & Administration Controller's Office Disbursement

  8. Office Buildings - Full Report

    Gasoline and Diesel Fuel Update (EIA)

    PDF Office Buildings Although no one building type dominates the commercial buildings sector, office buildings are the most common and account for more than 800,000 buildings or 17...

  9. Student Services Conference Office

    E-Print Network [OSTI]

    Sussex, University of

    Student Services Conference Office Guidelines VAT Exemption for Eligible Bodies #12;Student ........................................................................................................2 Applying the rules to Conferences is intended for use by the University of Sussex Conference Office to determine if an Organisation using

  10. Assistant Director (Commissioned Officer)

    E-Print Network [OSTI]

    Matrajt, Graciela

    Manager Maintenance Sup. II Bldg & Grounds Sup. B Program Ops Specialist Maintenance & Construction Coord. Coordinator Parking Enforcement Officer 2 - FTE Budget Analyst Cashier .5 FTE Parking Operations Officer 8

  11. Finance & Administration Controller's Office

    E-Print Network [OSTI]

    Finance & Administration Controller's Office July 2015 Michael Williams Assistant VP & Controller Thornton Exec. Support Assistant Administrative Services 57950 Cherrylyn Mills-Brown Office Administrator Administrative Services 51112 Judd Enfinger Associate Controller Accounting Services 60998 Sandra Scanlan

  12. Office of the Chief Information Officer DOERM@hq.doe.gov Office...

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

    Office of the Chief Information Officer DOERM@hq.doe.gov Office of IT Planning, Architecture and E-government Records Management Division (IM-23) Employee Separation:...

  13. InGaAsN/GaAs heterojunction for multi-junction solar cells

    DOE Patents [OSTI]

    Kurtz, Steven R. (Albuquerque, NM); Allerman, Andrew A. (Albuquerque, NM); Klem, John F. (Albuquerque, NM); Jones, Eric D. (Edgewood, NM)

    2001-01-01

    An InGaAsN/GaAs semiconductor p-n heterojunction is disclosed for use in forming a 0.95-1.2 eV bandgap photodetector with application for use in high-efficiency multi-junction solar cells. The InGaAsN/GaAs p-n heterojunction is formed by epitaxially growing on a gallium arsenide (GaAs) or germanium (Ge) substrate an n-type indium gallium arsenide nitride (InGaAsN) layer having a semiconductor alloy composition In.sub.x Ga.sub.1-x As.sub.1-y N.sub.y with 0GaAs layer, with the InGaAsN and GaAs layers being lattice-matched to the substrate. The InGaAsN/GaAs p-n heterojunction can be epitaxially grown by either molecular beam epitaxy (MBE) or metalorganic chemical vapor deposition (MOCVD). The InGaAsN/GaAs p-n heterojunction provides a high open-circuit voltage of up to 0.62 volts and an internal quantum efficiency of >70%.

  14. Band Structure of Strain-Balanced GaAsBi/GaAsN Super-lattices on GaAs

    SciTech Connect (OSTI)

    Hwang, J.; Phillips, J. D.

    2011-05-31

    GaAs alloys with dilute content of Bi and N provide a large reduction in band-gap energy with increasing alloy composition. GaAsBi/GaAsN heterojunctions have a type-II band alignment, where superlattices based on these materials offer a wide range for designing effective band-gap energy by varying superlattice period and alloy composition. The miniband structure and effective band gap for strain-balanced GaAsBi/GaAsN superlattices with effective lattice match to GaAs are calculated for alloy compositions up to 5% Bi and N using the k·p method. The effective band gap for these superlattices is found to vary between 0.89 and 1.32 eV for period thickness ranging from 10 to 100 Å. The joint density of states and optical absorption of a 40/40 Å GaAs0.96Bi0.04/GaAs0.98N0.02 superlattice are reported demonstrating a ground-state transition at 1.005 eV and first excited transition at 1.074 eV. The joint density of states is similar in magnitude to GaAs, while the optical absorption is approximately one order of magnitude lower due to the spatially indirect optical transition in the type-II structure. The GaAsBi/GaAsN system may provide a new material system with lattice match to GaAs in a spectral range of high importance for optoelectronic devices including solar cells, photodetectors, and light emitters.

  15. Magnetism and transport properties of epitaxial Fe-Ga thin films on GaAs(001)

    SciTech Connect (OSTI)

    Duong Anh Tuan; Shin, Yooleemi; Cho, Sunglae; Dang Duc Dung; Vo Thanh Son

    2012-04-01

    Epitaxial Fe-Ga thin films in disordered bcc {alpha}-Fe crystal structure (A2) have been grown on GaAs(001) by molecular beam epitaxy. The saturated magnetization (M{sub S}) decreased from 1371 to 1105 kA/m with increasing Ga concentration from 10.5 to 24.3 % at room temperature. The lattice parameter increased with the increase in Ga content because of the larger atomic radius of Ga atom than that of Fe. The increase in carrier density with Ga content caused in lower resistivity.

  16. Graphene induced remote surface scattering in graphene/AlGaN/GaN heterostructures

    SciTech Connect (OSTI)

    Liu, Xiwen; Li, Dan; Wang, Bobo; Liu, Bin; Chen, Famin; Jin, Guangri; Lu, Yanwu, E-mail: ywlu@bjtu.edu.cn [Department of Physics, Beijing Jiaotong University, Beijing 100044 (China)

    2014-10-20

    The mobilities of single-layer graphene combined with AlGaN/GaN heterostructures on two-dimensional electron gases in graphene/AlGaN/GaN double heterojunction are calculated. The impact of electron density in single-layer graphene is also studied. Remote surface roughness (RSR) and remote interfacial charge (RIC) scatterings are introduced into this heterostructure. The mobilities limited by RSR and RIC are an order of magnitude higher than that of interface roughness and misfit dislocation. This study contributes to designing structures for generation of higher electron mobility in graphene/AlGaN/GaN double heterojunction.

  17. Prepared October, 2015 Joseph Lachance, Ph.D.

    E-Print Network [OSTI]

    Weissburg, Marc

    population genetics2015 of randomly mating populations. Encyclopedia of Evolutionary Biology, edited by Orive of Biology Georgia Institute of Technology Atlanta, GA 30332 Office: 404-894-0794 Cell: 631-332-6112 joseph.lachance@biology.gatech.edu https://popgen.gatech.edu Educational Background: 1992-1996 A.B. in biology, University of Chicago

  18. Supplier Diversity Advocacy Meeting

    E-Print Network [OSTI]

    Pittendrigh, Barry

    APRIL 2015 EDITION UPCOMING EVENTS Supplier Diversity Advocacy Meeting April 7, 2015 Purdue Campus April 12-16, 2015 Atlanta, GA Contact: Publisher Office of Supplier Diversity Development Purdue University 401 S. Grant Street West Lafayette, IN 47907 Director of Supplier Diversity Development Jesse L

  19. OFFICE of the CHIEF INFORMATION SECURITY OFFICER

    E-Print Network [OSTI]

    Matrajt, Graciela

    security and privacy. Services are designed to help UW units understand risks by analyzing and forecasting Chief Information Security Officer In reflecting back on all our hard work during 2012, I would like of Contents Asset-Based Risk Management

  20. AlGaAsSb/GaSb Distributed Bragg Reflectors Grown by Organometallic Vapor Phase Epitaxy

    SciTech Connect (OSTI)

    C.A. Wang; C.J. Vineis; D.R. Calawa

    2002-02-13

    The first AlGaAsSb/GaSb quarter-wave distributed Bragg reflectors grown by metallic vapor phase epitaxy are reported. The peak reflectance is 96% for a 10-period structure.

  1. Impact of electrochemical process on the degradation mechanisms of AlGaN/GaN HEMTs

    E-Print Network [OSTI]

    Gao, Feng, Ph. D. Massachusetts Institute of Technology

    2014-01-01

    AlGaN/GaN high electron mobility transistors (HEMTs) constitute a new generation of transistors with excellent electrical characteristics and great potential to replace silicon technology in the future, especially in high ...

  2. GaN nanowires show more 3D piezoelectricity than bulk GaN

    E-Print Network [OSTI]

    Espinosa, Horacio D.

    director cds murder nudity soundtrack BBC movie releases footage worth documentary film Blu-rays Blu-ray Ga

  3. GaInP/GaAs/GaInAs Monolithic Tandem Cells for High-Performance Solar Concentrators

    SciTech Connect (OSTI)

    Wanlass, M. W.; Ahrenkiel, S. P.; Albin, D. S.; Carapella, J. J.; Duda, A.; Emery, K.; Geisz, J. F.; Jones, K.; Kurtz, S.; Moriarty, T.; Romero, M. J.

    2005-08-01

    We present a new approach for ultra-high-performance tandem solar cells that involves inverted epitaxial growth and ultra-thin device processing. The additional degree of freedom afforded by the inverted design allows the monolithic integration of high-, and medium-bandgap, lattice-matched (LM) subcell materials with lower-bandgap, lattice-mismatched (LMM) materials in a tandem structure through the use of transparent compositionally graded layers. The current work concerns an inverted, series-connected, triple-bandgap, GaInP (LM, 1.87 eV)/GaAs (LM, 1.42 eV)/GaInAs (LMM, {approx}1 eV) device structure grown on a GaAs substrate. Ultra-thin tandem devices are fabricated by mounting the epiwafers to pre-metallized Si wafer handles and selectively removing the parent GaAs substrate. The resulting handle-mounted, ultra-thin tandem cells have a number of important advantages, including improved performance and potential reclamation/reuse of the parent substrate for epitaxial growth. Additionally, realistic performance modeling calculations suggest that terrestrial concentrator efficiencies in the range of 40-45% are possible with this new tandem cell approach. A laboratory-scale (0.24 cm2), prototype GaInP/GaAs/GaInAs tandem cell with a terrestrial concentrator efficiency of 37.9% at a low concentration ratio (10.1 suns) is described, which surpasses the previous world efficiency record of 37.3%.

  4. Spontaneous emission in GaN/InGaN photonic crystal nanopillars

    E-Print Network [OSTI]

    Boyer, Edmond

    . Sigalas, "InGaN/GaN quantum-well heterostructure light-emitting diodes employing photonic crystal, "III-nitride blue and ultraviolet photonic crystal light emitting diodes," Appl. Phys. Lett. 84, 466, and H. Benisty, "Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution

  5. Switchable piezoelectric transduction in AlGaN/GaN MEMS resonators

    E-Print Network [OSTI]

    Weinstein, Dana

    This work presents a new switching mechanism in piezoelectric transduction of AlGaN/GaN bulk acoustic resonators. A piezoelectric transducer is formed in the AlGaN, between a top Schottky electrode and a 2D electron gas ...

  6. Office Of Nuclear Energy

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

    Office Of Nuclear Energy Sensors and Instrumentation Annual Review Meeting Enhanced Micro-Pocket Fission Detector (MPFD) for High Temperature Reactors Troy Unruh Idaho National...

  7. Office of Physical Protection

    Broader source: Energy.gov [DOE]

    The Office of Physical Protection is comprised of a team of security specialists engaged in providing Headquarters-wide physical protection.

  8. Government Printing Office Requirements

    Broader source: Energy.gov [DOE]

    This section describes the Government Printing Office (GPO) requirements for all print materials, whether printed electronically or on paper. This includes requirements for printing and copying for...

  9. Site Office Manager, Princeton

    Broader source: Energy.gov [DOE]

    A successful candidate in this position will serve as the Princeton Site Office (PSO) Manager by providing overall executive leadership to the PSO.

  10. Vehicle Technologies Office: News

    Broader source: Energy.gov [DOE]

    EERE intends to issue, on behalf of its Fuel Cell Technologies Office, a Funding Opportunity Announcement (FOA) entitled "Fuel Cell Technologies Incubator: Innovations in Fuel Cell and Hydrogen...

  11. Building Technologies Office

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

    Technologies Office Richard Karney, P.E. May 8, 2014 40% 60% National Energy Consumption Reducing consumption or improving performance calls for cutting-edge...

  12. Solar Energy Technologies Office

    Office of Energy Efficiency and Renewable Energy (EERE)

    In 2011, the Energy Department's Solar Energy Technologies Office (SETO) became the SunShot Initiative, a collaborative national effort that aggressively drives innovation to make solar energy...

  13. Sustainability Performance Office | Department of Energy

    Office of Environmental Management (EM)

    Performance Office Sustainability Performance Office The U.S. Department of Energy (DOE) Sustainability Performance Office (SPO) oversees departmental sustainability...

  14. Scientific Achievement Networks of highly photoresponsive crystalline GaSe

    E-Print Network [OSTI]

    Geohegan, David B.

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

  15. UC Sustainability Office Report

    E-Print Network [OSTI]

    Hickman, Mark

    UC Sustainability Office Report Introduction Welcome to the third annual UC Sustainability Office infrastructure, UC is now trending in a positive direction against some sustainability indicators. Electricity products and membership of the UC Sustainability Community is growing. There are concerns around the amount

  16. FRASER POLLUTION ABATEMENT OFFICE

    E-Print Network [OSTI]

    #12;-. FRASER POLLUTION ABATEMENT OFFICE 1992-93 Progress Report By MaggieM. Paquet MAIAPublishingLtd. 302 E. 6th Street NorthVancouver,BC V7L 1P6 For FraserPollutionAbatementOffice EnvironmentCanada 224W objectives of FRAP is to clean up pollution in the Fraser River Basin. This objective depends on pollution

  17. FRASER POLLUTION ABATEMENT OFFICE

    E-Print Network [OSTI]

    #12;FRASER POLLUTION ABATEMENT OFFICE PROGRESS REPORT 1994-95 Prepared By Maggie M. Paquet MAIA Publishing Ltd. Vancouver, BC For Technology and Pollution Prevention Section Fraser River Action Plan Environment Canada, FPAO Progress Report 1994-1995 ACKNOWLEDGEMENTS The Fraser Pollution Abatement Office

  18. Europaisches Patent Office

    E-Print Network [OSTI]

    Vertes, Akos

    (19) (12) Europaisches Patentamt European Patent Office Office europeen des brevets 11111~11111111111111111"11111111111111111"11""1111111111II~,,~1111 (11) EP 2 356 668 81 EUROPEAN PATENT SPECIFICATION (86) International application number: PCT/US2009/065891 (45) Date of publication and mention of the grant of the patent: 17.07.2013 Bulletin

  19. KALELE ROAD Parking Office

    E-Print Network [OSTI]

    FREEWAY H1 KALELE ROAD Parking Office on ground floor Bike Rack Locations Bike Lockers BICYCLE RACK Hale Kahawai Environmental Protection Services Federal Credit Union Energy House & Safety Office Bus Shelter Bus Shelter Art Building Sustainability Courtyard Kuykendall Hall Campus Center Jakuan Tea

  20. Appointment of Contracting Officers and Contracting Officer Representatives

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2004-04-21

    The Order established procedures governing the selection, appointment and termination of Department of Energy contracting officers and contracting officer representatives. Supersedes DOE O 541.1A.

  1. The Office of Independent Enterprise Assessments' Office of Enforcemen...

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

    Steve Simonson, Director of the Office of Enforcement, addresses the 2014 DOE Safety and Security Enforcement Workshop attendees. Steve Simonson, Director of the Office of...

  2. Development of metallization for GaAs and AlGaAs concentrator solar cells

    SciTech Connect (OSTI)

    Tobin, S.P.

    1987-04-01

    A three-layer metallization system was developed for high temperature stability on GaAs and AlGaAs solar cells. The layers are a Pt ohmic contact metal that forms thermally stable compounds with GaAs, a TiN diffusion barrier, and a gold conductor. The solar cell structure was also designed for contact stability, with the key component being a heavily doped GaAs cap layer. Reactively sputtered TiN was found to act as an excellent barrier when deposited under the proper conditions. The conditions were carefully optimized for low resistivity and low stress in the films. A low but nonzero substrate bias during sputtering was found to be important. Solar cells with sputtered metallizations of Pt/TiN/Ti/Pt/Au were found to be thermally stable up to 500/sup 0/C for 15 minutes in vacuum. At 600/sup 0/C there was catastrophic degradation of the cells due to dissociation of uncapped GaAs surfaces. Below this temperature the metallization performed as designed. The Pt and GaAs layers reacted to form a stable PtGa compound layer that gave low contact resistance. There was no penetration of Au or GaAs through the barrier layer. These results are a very encouraging first step leading to stable, reliable GaAs and AlGaAs concentrator cells.

  3. Office of International Education International Student, Scholar, and Immigration Services (ISSIS)

    E-Print Network [OSTI]

    Arnold, Jonathan

    1 Rev. 01-12 Office of International Education International Student, Scholar, and Immigration Services (ISSIS) 1324 S. Lumpkin Street, Athens, GA 30602-5407 issis@uga.edu (706) 542-2900 fax: (706) 583 may request reinstatement from the U.S. Citizenship & Immigration Services (USCIS). The USCIS has

  4. Office of International Education International Student, Scholar, and Immigration Services (ISSIS)

    E-Print Network [OSTI]

    Arnold, Jonathan

    1 Rev. 01-12 Office of International Education International Student, Scholar, and Immigration Services (ISSIS) 1324 S. Lumpkin Street, Athens, GA 30602-5407 issis@uga.edu (706) 542-2900 fax: (706) 583 will "fulfill the educational objectives for his or her current degree program at his or her home institution

  5. Office of International Education International Student, Scholar, and Immigration Services (ISSIS)

    E-Print Network [OSTI]

    Arnold, Jonathan

    1 Rev. 01-12 Office of International Education International Student, Scholar, and Immigration Services (ISSIS) 1324 S. Lumpkin Street, Athens, GA 30602-5407 issis@uga.edu (706) 542-2900 fax: (706) 583 provides direct services to students. If you are unclear if a job would be considered "on

  6. Office of International Education International Student, Scholar, and Immigration Services (ISSIS)

    E-Print Network [OSTI]

    Arnold, Jonathan

    1 Rev. 11-11 Office of International Education International Student, Scholar, and Immigration Services (ISSIS) 1324 S. Lumpkin Street, Athens, GA 30602-5407 issis@uga.edu (706) 542-2900 fax: (706) 583 & Immigration Services (ISSIS) RE: USCIS ELIS Filing Program, and Submission of Form I-20 or DS-2019 in support

  7. Office of International Education International Student, Scholar, and Immigration Services (ISSIS)

    E-Print Network [OSTI]

    Arnold, Jonathan

    1 Rev. 03-15 Office of International Education International Student, Scholar, and Immigration Services (ISSIS) 1324 S. Lumpkin Street, Athens, GA 30602-5407 issis@uga.edu (706) 542-2900 fax: (706) 583 as the employment provides direct services to students. If you are unclear if a job would be considered "on

  8. Structural and optical properties of InGaN–GaN nanowire heterostructures grown by molecular beam epitaxy

    SciTech Connect (OSTI)

    Limbach, F.; Gotschke, T.; Stoica, T.; Calarco, R.; Sutter, E.; Ciston, J.; Cusco, R.; Artus, L.; Kremling, S.; Ho?fling, S.; Worschech, L.; Gru?tzmacher, D.

    2011-01-01

    InGaN/GaN nanowire (NW) heterostructures grown by plasma assisted molecular beam epitaxy were studied in comparison to their GaN and InGaN counterparts. The InGaN/GaN heterostructure NWs are composed of a GaN NW, a thin InGaN shell, and a multifaceted InGaN cap wrapping the top part of the GaN NW. High-resolution transmission electron microscopy (HRTEM) images taken from different parts of a InGaN/GaN NW show a wurtzite structure of the GaN core and the epitaxial InGaN shell around it, while additional crystallographic domains are observed whithin the InGaN cap region. Large changes in the lattice parameter along the wire, from pure GaN to higher In concentration demonstrate the successful growth of a complex InGaN/GaN NW heterostructure. Photoluminescence (PL) spectra of these heterostructure NW ensembles show rather broad and intense emission peak at 2.1 eV. However, ?-PL spectra measured on single NWs reveal a reduced broadening of the visible luminescence. The analysis of the longitudinal optical phonon Raman peak position and its shape reveal a variation in the In content between 20% and 30%, in agreement with the values estimated by PL and HRTEM investigations. The reported studies are important for understanding of the growth and properties of NW heterostructures suitable for applications in optoelectronics and photovoltaics.

  9. Secondary structure and domain architecture of the 23S and 5S rRNAs

    E-Print Network [OSTI]

    Williams, Loren

    Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA, 4 Department of Biology and Biochemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA, 2 Center for Ribosomal Origins

  10. On the effect of dust particles on global CCN and cloud droplet number1 V.A. Karydis1

    E-Print Network [OSTI]

    Nenes, Athanasios

    Institute of Technology, Atlanta,4 GA5 3 SABIC-Innovative Plastics, Selkirk, NY6 4 NASA Goddard Space Flight, Georgia Institute of Technology, Atlanta, GA3 2 School of Chemical and Biomolecular Engineering, Georgia

  11. Atmos. Chem. Phys., 11, 86618676, 2011 www.atmos-chem-phys.net/11/8661/2011/

    E-Print Network [OSTI]

    Meskhidze, Nicholas

    of Technology, Atlanta, GA, 30332, USA 2School of Earth & Atmospheric Sciences, Georgia Institute of Technology Atlanta, GA, 30332, USA *now at: SABIC-Innovative Plastics, 1 Noryl Avenue, Selkirk, NY, 12158, USA

  12. Indoor Air Quality Assessment of the San Francisco Federal Building

    E-Print Network [OSTI]

    Apte, Michael

    2010-01-01

    References ASHRAE. 1999. ANSI/ASHRAE Standard 129-199,Atlanta GA. ASHRAE. 2004. ANSI/ASHRAE Standard 55, ThermalAtlanta GA. ASHRAE. 2007. ANSI/ASHRAE Standard 62.1,

  13. Georgia Tech Manufacturing Institute | 813 Ferst Drive, N.W. | Atlanta, GA 30332-0560 | (404) 894-9100 | www.manufacturing.gatech.edu Manufacturing is in Georgia Tech's DNA: GTMI Binds it Together

    E-Print Network [OSTI]

    Das, Suman

    -suited for the rapidly evolving world of manufacturing. Collaboration and Innovation are Core Strengths Among GTMI partners · Awarded a grant to develop and lead the Consortium for Accelerated Innovation and Insertion for electronics, solar energy, woodworking and precision machining industries that allow companies to easily work

  14. Institute for Electronics and Nanotechnology | Georgia Institute of Technology 345 Ferst Drive NW | Atlanta, GA 30318 | 404.894.5100 | info@ien.gatech.edu | www.ien.gatech.edu

    E-Print Network [OSTI]

    Garmestani, Hamid

    Scientific K-Alpha XPS X-ray Photoelectron Spectroscope > Selectable area spectroscopy and Ar sputter depth conductive-AFM and magnetic force microscopy > Provides analysis data on the electrical and mechanical Spectrometer > Excellent for characterizing multi-layer laminates, thin films, inclusions and subsurface

  15. Georgia Tech Manufacturing Institute | 813 Ferst Drive, N.W. | Atlanta, GA 30332-0560 | (404) 894-9100 | www.manufacturing.gatech.edu Point of View: The Internet of Things for Manufacturing

    E-Print Network [OSTI]

    Das, Suman

    -9100 | www.manufacturing.gatech.edu Point of View: The Internet of Things for Manufacturing (IoTfM) By Introduction The Internet of Things is predicted to have a huge impact on the future of manu- facturing. According to the Industrial IP Advantage resource center, the Internet of Things has an estimated value

  16. Ohmic contacts to n-GaSb 

    E-Print Network [OSTI]

    Yang, Zhengchong

    1997-01-01

    In recent years, the Ill-V semiconductor GaSb and its ternary alloys containing antimony have exhibited interesting electrical and optical properties for device applications which include negative resistance tunnel devices, lasers, detectors and FET...

  17. Workforce Management Office (WFMO) Functional Statements WORKFORCE MANAGEMENT OFFICE

    E-Print Network [OSTI]

    May 2014 Workforce Management Office (WFMO) ­ Functional Statements WORKFORCE MANAGEMENT OFFICE The Workforce Management Office (WFMO) is the servicing Human Resource Organization for NOAA and is the principal contact point with the Department of Commerce (DOC) Office of Human Resources Management. WFMO

  18. GaTe semiconductor for radiation detection

    DOE Patents [OSTI]

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

    2009-06-23

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

  19. Supervisory Program Analysis Officer

    Broader source: Energy.gov [DOE]

    A successful candidate in this position will be responsible for the program analysis and evaluation of all activities which fall within the purview of the Office. The incumbent directs a moderate...

  20. Office of Information Security

    Broader source: Energy.gov [DOE]

    The Office of Information Security is responsible for implementation of the Classified Matter Protection and Control Program (CMPC), the Operations Security Program (OPSEC) and the Facility Clearance Program and the Survey Program for Headquarters

  1. Oak Ridge Office

    Office of Environmental Management (EM)

    - Mr. Steve Dixon, Chairman Oak Ridge Site Specific Advisory Board Post Office Box 200 1 Oak Ridge, Tennessee 3 783 0 Dear Mr. Dixon: RESPONSE TO RECOMMENDATION ON PROVIDING...

  2. Office of Security Policy

    Broader source: Energy.gov [DOE]

    The Office of Security Policy is the central source within the Department of Energy for the development and analysis of safeguards and security policies and standards affecting facilities, nuclear materials, personnel, and classified information.

  3. Portsmouth Paducah Project Office

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy (DOE) established the Portsmouth/Paducah Project Office (PPPO) on October 1, 2003, to provide focused leadership to the Environmental Management missions at the...

  4. User Liaison Office

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

    Office Space User space is available in the ARC, reserve space here. arc-thumb.jpg Click to see Virtual Tour 12000 Jefferson Avenue, Newport News, VA 23606 Phone: (757) 269-7255...

  5. Oak Ridge Office

    Office of Environmental Management (EM)

    PO. Box 2001 Oak Ridge, Tennessee 37831 July 21, 2010 Mr. Ron Murphree, Chair Oak Ridge Site Specific Advisory Board Post Office Box 200 1 Oak Ridge, Tennessee 3783 1 Dear Mr....

  6. Manager, Golden Field Office

    Broader source: Energy.gov [DOE]

    This position is located in the Office of Energy Efficiency and Renewable Energy (EERE). The mission of EERE is to create and sustain American leadership in the global transition to a clean energy...

  7. Director, Office of Research

    Broader source: Energy.gov [DOE]

    Within the Department of Energy, the Office of Fossil Energy (FE) plays a key role in helping the United States meet its continually growing need for secure, reasonably priced and environmentally...

  8. DEPARTMENT OF I Office

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

    SLAC Site Office Enter APS report date here Linac Coherent Light Source-II, Menlo Park, California (EA No. DOEEA-1904) 115,000 The proposed Linac Coherent Light Source...

  9. Office of Nuclear Safety

    Broader source: Energy.gov [DOE]

    The Office of Nuclear Safety establishes nuclear safety requirements and expectations for the Department to ensure protection of workers and the public from the hazards associated with nuclear operations with all Department operations.

  10. Office of Fossil Energy

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

    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 Delicious RankADVANCED MANUFACTURINGEnergy Bills and ReduceNovemberDOE's PrioritiesOctober 2013CommentsOfficeOffice

  11. Office of Personnel Management

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties -DepartmentAvailableHighOffice of Indian Energy PolicyOffice0

  12. Chief Technology Officer Opportunity Profile

    E-Print Network [OSTI]

    Mazzotti, Frank

    Chief Technology Officer Opportunity Profile #12;CHIEF TECHNOLOGY OFFICER Date: 01/23/2015 Prepared for the position and to give a deeper understanding of the role of Chief Technology Officer. We have also included: POSITION ANNOUNCEMENT TAB V: THE REGION TAB I: POSITION ANNOUNCEMENT #12;Chief Technology Officer

  13. InGaN/GaN tunnel junctions for hole injection in GaN light emitting diodes

    SciTech Connect (OSTI)

    Krishnamoorthy, Sriram, E-mail: krishnamoorthy.13@osu.edu, E-mail: rajan@ece.osu.edu; Akyol, Fatih [Department of Electrical and Computer Engineering, The Ohio State University, Columbus, Ohio 43210 (United States); Rajan, Siddharth, E-mail: krishnamoorthy.13@osu.edu, E-mail: rajan@ece.osu.edu [Department of Electrical and Computer Engineering, The Ohio State University, Columbus, Ohio 43210 (United States); Department of Materials Science and Engineering, The Ohio State University, Columbus, Ohio 43210 (United States)

    2014-10-06

    InGaN/GaN tunnel junction contacts were grown using plasma assisted molecular beam epitaxy (MBE) on top of a metal-organic chemical vapor deposition (MOCVD)-grown InGaN/GaN blue (450?nm) light emitting diode. A voltage drop of 5.3?V at 100?mA, forward resistance of 2 × 10{sup ?2} ? cm{sup 2}, and a higher light output power compared to the reference light emitting diodes (LED) with semi-transparent p-contacts were measured in the tunnel junction LED (TJLED). A forward resistance of 5?×?10{sup ?4} ? cm{sup 2} was measured in a GaN PN junction with the identical tunnel junction contact as the TJLED, grown completely by MBE. The depletion region due to the impurities at the regrowth interface between the MBE tunnel junction and the MOCVD-grown LED was hence found to limit the forward resistance measured in the TJLED.

  14. Journal of Crystal Growth 298 (2007) 272275 Dislocation analysis in homoepitaxial GaInN/GaN light emitting

    E-Print Network [OSTI]

    Wetzel, Christian M.

    2007-01-01

    of GaInN/GaN-based light emitting diodes (LED) on quasi-bulk GaN with an atomically flat polished were much improved. The optical output power of the light emitting diode increased by more than one. Cathodoluminescence; A1. Threading dislocation density; A2. Homoepitaxial growth; B1. GaInN; B3. Light emitting diode

  15. Thermoelectric effects in wurtzite GaN and AlxGa1-xN alloys and Alexander A. Balandin

    E-Print Network [OSTI]

    Thermoelectric effects in wurtzite GaN and AlxGa1-xN alloys Weili Liua and Alexander A. Balandin have investigated theoretically the thermoelectric effects in wurtzite GaN crystals and AlxGa1-xN-based alloys may have some potential as thermoelectric materials at high temperature. It was found

  16. 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.

  17. Office Buildings - Types of Office Buildings

    Gasoline and Diesel Fuel Update (EIA)

    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 Natural GasAdjustments (Billion Cubic Feet)Decade Year-0 Year-1 Year-2 Year-3 Year-4Barrels)(Dollars2.PDF Office

  18. Green cubic GaInN/GaN light-emitting diode on microstructured silicon (100)

    SciTech Connect (OSTI)

    Stark, Christoph J. M.; Detchprohm, Theeradetch; Wetzel, Christian, E-mail: wetzel@ieee.org [Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States) [Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States); Future Chips Constellation, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180 (United States); Lee, S. C.; Brueck, S. R. J. [Department of Electrical and Computer Engineering and Center for High Technology Materials, University of New Mexico, 1313 Goddard SE, Albuquerque, New Mexico 87106 (United States)] [Department of Electrical and Computer Engineering and Center for High Technology Materials, University of New Mexico, 1313 Goddard SE, Albuquerque, New Mexico 87106 (United States); Jiang, Y.-B. [Department of Earth and Planetary Science, University of New Mexico, Albuquerque, New Mexico 87131 (United States)] [Department of Earth and Planetary Science, University of New Mexico, Albuquerque, New Mexico 87131 (United States)

    2013-12-02

    GaInN/GaN light-emitting diodes free of piezoelectric polarization were prepared on standard electronic-grade Si(100) substrates. Micro-stripes of GaN and GaInN/GaN quantum wells in the cubic crystal structure were grown on intersecting (111) planes of microscale V-grooved Si in metal-organic vapor phase epitaxy, covering over 50% of the wafer surface area. Crystal phases were identified in electron back-scattering diffraction. A cross-sectional analysis reveals a cubic structure virtually free of line defects. Electroluminescence over 20 to 100??A is found fixed at 487?nm (peak), 516?nm (dominant). Such structures therefore should allow higher efficiency, wavelength-stable light emitters throughout the visible spectrum.

  19. A hole accelerator for InGaN/GaN light-emitting diodes

    SciTech Connect (OSTI)

    Zhang, Zi-Hui; Liu, Wei; Tan, Swee Tiam; Ji, Yun; Wang, Liancheng; Zhu, Binbin; Zhang, Yiping; Lu, Shunpeng; Zhang, Xueliang; Hasanov, Namig; Sun, Xiao Wei, E-mail: EXWSUN@ntu.edu.sg, E-mail: VOLKAN@stanfordalumni.org [LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Mathematical Sciences, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Demir, Hilmi Volkan, E-mail: EXWSUN@ntu.edu.sg, E-mail: VOLKAN@stanfordalumni.org [LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Mathematical Sciences, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Department of Electrical and Electronics, Department of Physics, and UNAM-Institute of Material Science and Nanotechnology, Bilkent University, TR-06800 Ankara (Turkey)

    2014-10-13

    The quantum efficiency of InGaN/GaN light-emitting diodes (LEDs) has been significantly limited by the insufficient hole injection, and this is caused by the inefficient p-type doping and the low hole mobility. The low hole mobility makes the holes less energetic, which hinders the hole injection into the multiple quantum wells (MQWs) especially when a p-type AlGaN electron blocking layer (EBL) is adopted. In this work, we report a hole accelerator to accelerate the holes so that the holes can obtain adequate kinetic energy, travel across the p-type EBL, and then enter the MQWs more efficiently and smoothly. In addition to the numerical study, the effectiveness of the hole accelerator is experimentally shown through achieving improved optical output power and reduced efficiency droop for the proposed InGaN/GaN LED.

  20. Gallium surface diffusion on GaAs (001) surfaces measured by crystallization dynamics of Ga droplets

    SciTech Connect (OSTI)

    Bietti, Sergio, E-mail: sergio.bietti@mater.unimib.it; Somaschini, Claudio; Esposito, Luca; Sanguinetti, Stefano [L–NESS and Dipartimento di Scienza dei Materiali, Università di Milano Bicocca, Via Cozzi 55, I–20125 Milano (Italy); Fedorov, Alexey [L–NESS and CNR–IFN, via Anzani 42, I-22100 Como (Italy)

    2014-09-21

    We present accurate measurements of Ga cation surface diffusion on GaAs surfaces. The measurement method relies on atomic force microscopy measurement of the morphology of nano–disks that evolve, under group V supply, from nanoscale group III droplets, earlier deposited on the substrate surface. The dependence of the radius of such nano-droplets on crystallization conditions gives direct access to Ga diffusion length. We found an activation energy for Ga on GaAs(001) diffusion E{sub A}=1.31±0.15 eV, a diffusivity prefactor of D?=0.53(×2.1±1) cm² s?¹ that we compare with the values present in literature. The obtained results permit to better understand the fundamental physics governing the motion of group III ad–atoms on III–V crystal surfaces and the fabrication of designable nanostructures.

  1. Badging, Badge Office

    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 ActTools toBadging, Badge Office Badging, Badge Office

  2. Fermilab | Directorate | Offices

    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) | SciTech ConnectTimothyOffices Office of Integrated

  3. Office Buildings - Full Report

    U.S. Energy Information Administration (EIA) Indexed Site

    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 PageMonthly","10/2015"4,"Ames5 Tables July 1996 Energy Information Administration Office of Coal, Nuclear,DecadeYear Jan FebElements)Feet) Decade8PDF Office

  4. GaN: Defect and Device Issues

    SciTech Connect (OSTI)

    Pearton, S.J.; Ren, F.; Shul, R.J.; Zolper, J.C.

    1998-11-09

    The role of extended and point defects, and key impurities such as C, O and H, on the electrical and optical properties of GaN is reviewed. Recent progress in the development of high reliability contacts, thermal processing, dry and wet etching techniques, implantation doping and isolation and gate insulator technology is detailed. Finally, the performance of GaN-based electronic and photonic devices such as field effect transistors, UV detectors, laser diodes and light-emitting diodes is covered, along with the influence of process-induced or grown-in defects and impurities on the device physics.

  5. Office of Heath, Safety and Security Now Two New Offices

    Office of Energy Efficiency and Renewable Energy (EERE)

    To serve you better, DOE has structured the former HSS into to new organizations: the Office Independent Enterprise Assessment (IEA); and Office of Environment, Health, Safety and Security (EHSS).

  6. UMass Office of Information Technologies Office of Information Technologies

    E-Print Network [OSTI]

    Mountziaris, T. J.

    UMass Office of Information Technologies Office of Information Technologies A218 Lederle GRC University of Massachusetts Amherst http://www.oit.umass.edu/ The Instructor's Guide to Information Security 1. Student Information at UMass Amherst What is FERPA anyway

  7. Appointment of Contracting Officers and Contracting Officer Representatives

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1996-04-30

    To establish procedures governing the selection, appointment, and termination of contracting officers and for the appointment of contracting officer representatives. Cancels DOE Order 4200.4A. Canceled by DOE O 541.1A.

  8. Influence of pressure on photoluminescence and electroluminescence in GaN/InGaN/AlGaN quantum wells

    E-Print Network [OSTI]

    Weinstein, Benard.A.

    recently that the temperature shifts of the photo- and electroluminescence EL peak energies in Nichia greenV/GPa for the green and blue diodes, respectively. The observed pressure coefficients are much lower than those characteristic of the energy gap in GaN ( 40 meV/GPa) or the energy gap in InN ( 33 meV/GPa). This kind

  9. A multicolor, broadband (520m), quaternary-capped InAs/GaAs quantum dot infrared photodetector

    E-Print Network [OSTI]

    Perera, A. G. Unil

    , Mumbai 400076, India 2 Department of Physics & Astronomy, Georgia State University, Atlanta, Georgia. Using strain field and multi-band k Á p theory, we map specific bound-to-bound and bound

  10. Vehicle Technologies Office: Events | Department of Energy

    Office of Environmental Management (EM)

    Vehicle Technologies Office: Events Vehicle Technologies Office: Events The Vehicle Technologies Office holds a number of events to advance research, development and deployment of...

  11. Nevada Field Office | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    Us Our Operations Management and Budget Office of Civil Rights Workforce Statistics Nevada Field Office Nevada Field Office FY15 Semi Annual Report FY14 Year End...

  12. Sandia Field Office | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    Us Our Operations Management and Budget Office of Civil Rights Workforce Statistics Sandia Field Office Sandia Field Office FY15 Semi Annual Report FY14 Year End...

  13. Livermore Field Office | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    Us Our Operations Management and Budget Office of Civil Rights Workforce Statistics Livermore Field Office Livermore Field Office FY15 Semi Annual Report FY14 Year...

  14. Pantex Field Office | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    Us Our Operations Management and Budget Office of Civil Rights Workforce Statistics Pantex Field Office Pantex Field Office FY12 Semi Annual Report FY11 Year End...

  15. Contact the Sustainability Performance Office | Department of...

    Office of Environmental Management (EM)

    Performance Office Contact the Sustainability Performance Office The U.S. Department of Energy (DOE) Sustainability Performance Office (SPO) oversees departmental sustainability...

  16. InGaAs/GaAs quantum dot interdiffiusion induced by cap layer overgrowth

    SciTech Connect (OSTI)

    Jasinski, J.; Babinski, A.; Czeczott, M.; Bozek, R.

    2000-06-28

    The effect of thermal treatment during and after growth of InGaAs/GaAs quantum dot (QD) structures was studied. Transmission electron microscopy and atomic force microscopy confirmed the presence of interacting QDs, as was expected from analysis of temperature dependence of QD photoluminescence (PL) peak. The results indicate that the effect of post-growth annealing can be similar to the effect of elevated temperature of capping layer growth. Both, these thermal treatments can lead to a similar In and Ga interdiffiusion resulting in a similar blue-shift of QD PL peak.

  17. Optical spectroscopy of quantum confined states in GaAs/AlGaAs quantum well tubes

    SciTech Connect (OSTI)

    Shi, Teng; Fickenscher, Melodie; Smith, Leigh; Jackson, Howard; Yarrison-Rice, Jan; Gao, Qiang; Tan, Hoe; Jagadish, Chennupati; Etheridge, Joanne; Wong, Bryan M.

    2013-12-04

    We have investigated the quantum confinement of electronic states in GaAs/Al{sub x}Ga{sub 1?x}As nanowire heterostructures which contain radial GaAs quantum wells of either 4nm or 8nm. Photoluminescence and photoluminescence excitation spectroscopy are performed on single nanowires. We observed emission and excitation of electron and hole confined states. Numerical calculations of the quantum confined states using the detailed structural information on the quantum well tubes show excellent agreement with these optical results.

  18. Appointment of Contracting Officers and Contracting Officer's Representatives

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2000-10-27

    To establish procedures governing the selection, appointment, and termination of contracting officers and for the appointment of contracting officer's representatives. To ensure that only trained and qualified procurement and financial assistance professionals, within the scope of this Order, serve as contracting officers. Cancels DOE O 541.1. Canceled by DOE O 541.1B.

  19. PARKING MAP Sales Office

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    PARKING MAP BayDr. Main Entrance Parking Sales Office Main Entrance Kiosk East Remote Lot for details DMV Parking Transit Stop Traffic Signal PARTIAL OR FULL LOT CLOSURE Crown Lot 111 Kresge Lot 147M--close-in parking for undergraduate students (lot-specific) EV--charging for electric vehicles MC

  20. PARKING MAP Sales Office

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    PARKING MAP BayDr. Main Entrance Parking Sales Office Main Entrance Kiosk East Remote Lot Parking Transit Stop Traffic Signal PARTIAL OR FULL LOT CLOSURE Stevenson Lot 110 Crown Lot 111 Merrill student parking C--close-in parking for undergraduate students (lot-specific) EV--charging for electric

  1. Registered Student Organization Officer

    E-Print Network [OSTI]

    Raina, Ramesh

    website: gradorg.syr.edu #12;Important Information Registered Graduate Student Organization Handbook Fiscal Policy document provides additional fiscal guidelines and procedures ­ The Fiscal Policy can with Office of Student Activities If any of the required information changes, contact Internal VP

  2. Accommodation Office Housing Fair

    E-Print Network [OSTI]

    Bristol, University of

    Accommodation Office Housing Fair 11 am to 4 pm December 10th 2014 Wills Great Hall bristol accommodation, Waterlane Apartments, College Green & Fusion Towers offer a mix of studios and two bedroomed, with a range of flats and houses, and room sizes from 1 to 12. Our list of properties for academic year 2015

  3. Sustainable Office Lighting Options

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    Sustainable Office Lighting Options Task Lighting: Task lighting is a localized method of lighting a workspace so that additional, unnecessary lighting is eliminated, decreasing energy usage and costs. Illumination levels in the targeted work areas are higher with task lighting than with the ambient levels

  4. Office of Document Reviews

    Broader source: Energy.gov [DOE]

    The Office of Document Reviews ensures that all documents prepared at DOE Headquarters are properly marked to identify the level and category of protected information they contain (if any) and to ensure that all documents the Department prepares or is required to review under applicable statutes for public release contain no information requiring protection under law, regulations and Executive orders.

  5. Chief Financial Officer Responsibilities

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2006-11-21

    The Order sets forth requirements for operating the Department of Energy in full compliance with the Chief Financial Officers Act of 1990 and sets standards for sound financial management policies and practices, effective internal controls, accurate and timely financial information, and well-qualified financial managers. Supersedes DOE O 520.1.

  6. Office of Quality Management

    Office of Energy Efficiency and Renewable Energy (EERE)

    The Office of Quality Management develops and interprets Government-wide policies and procedures and conducts training to ensure the accurate identification of information and documents that must be classified or controlled under statute or Executive order to protect the national security and controlled unclassified Official Use Only information for the effective operation of the Government.

  7. OFFICE FOR EMERGENCY MANAGEMENT

    Office of Legacy Management (LM)

    OFFICE FOR EMERGENCY MANAGEMENT 155OP STREETNW. WiSHINGTON. D.C. ' , iQns 25,19&L At-t :. I' .' at l530 P Btmat, IO&, XtwMn&m, 0. 6., at 9130 A.Jb Sa 1 llmbemupoftbaaomlttaal8f...

  8. Structural and optical properties of InGaN–GaN nanowire heterostructures grown by molecular beam epitaxy

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

    Limbach, F.; Gotschke, T.; Stoica, T.; Calarco, R.; Sutter, E.; Ciston, J.; Cusco, R.; Artus, L.; Kremling, S.; Ho?fling, S.; et al

    2011-01-01

    InGaN/GaN nanowire (NW) heterostructures grown by plasma assisted molecular beam epitaxy were studied in comparison to their GaN and InGaN counterparts. The InGaN/GaN heterostructure NWs are composed of a GaN NW, a thin InGaN shell, and a multifaceted InGaN cap wrapping the top part of the GaN NW. High-resolution transmission electron microscopy (HRTEM) images taken from different parts of a InGaN/GaN NW show a wurtzite structure of the GaN core and the epitaxial InGaN shell around it, while additional crystallographic domains are observed whithin the InGaN cap region. Large changes in the lattice parameter along the wire, from pure GaNmore »to higher In concentration demonstrate the successful growth of a complex InGaN/GaN NW heterostructure. Photoluminescence (PL) spectra of these heterostructure NW ensembles show rather broad and intense emission peak at 2.1 eV. However, ?-PL spectra measured on single NWs reveal a reduced broadening of the visible luminescence. The analysis of the longitudinal optical phonon Raman peak position and its shape reveal a variation in the In content between 20% and 30%, in agreement with the values estimated by PL and HRTEM investigations. The reported studies are important for understanding of the growth and properties of NW heterostructures suitable for applications in optoelectronics and photovoltaics.« less

  9. Deputy Director, Advanced Manufacturing Office

    Broader source: Energy.gov [DOE]

    This position is located in the Advanced Manufacturing Office (AMO), within the Office of Energy Efficiency and Renewable Energy (EERE). EERE leads the U.S. Department of Energy's efforts to...

  10. Energy efficiency in office technology

    E-Print Network [OSTI]

    Dandridge, Cyane Bemiss

    1994-01-01

    This thesis, directed toward a wide variety of persons interested in energy efficiency issues with office technology, explores several issues relating to reducing energy use and improving energy efficiency of office ...

  11. Comments from Nebraska's Energy Office.

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    Web Site at >http:www.neo.ne.gov<. Feedback for Proposed Collection of Densified Biomass Fuel Data Nebraska Energy Office Page 2 Doris A. Jansky Nebraska Energy Office...

  12. Europaisches Patentamt European Patent Office

    E-Print Network [OSTI]

    Church, George M.

    Europaisches Patentamt European Patent Office Office europeen des brevets ® Publication number: o 303 459 A2 @ EUROPEAN PATENT APPLICATION ® Application number: 88307391.8 @ Int. C1.4: C 12 Q 1

  13. Office of Information Technology Accomplishments

    E-Print Network [OSTI]

    Yorke, James

    Office of Information Technology Accomplishments Fiscal Year 2007 #12;Office of Information'scentralinformationtechnologyserviceorganization,itismypleasuretosharewithyou theOfficeofInformationTechnology'spublication,"OITAccomplishmentsFiscalYear2007,"whichfeatures's goal is to take a quantum leap forward in the information technology environmentavailabletostudents

  14. Defect studies in low-temperature-grown GaAs

    SciTech Connect (OSTI)

    Bliss, D.E.

    1992-11-01

    High content of excess As is incorporated in GaAs grown by low-temperature molecular-beam-epitaxy (LTMBE). The excess As exists primarily as As antisite defects AsGa and a lesser extent of gallium vacancies V[sub Ga]. The neutral AsGa-related defects were measured by infrared absorption at 1[mu]m. Gallium vacancies, V[sub Ga], was investigated by slow positron annihilation. Dependence of defect contents on doping was studied by Si and Be dopants. No free carriers are generated by n-type or p-type doping up to 10[sup 19] cm[sup [minus]3] Si or Be. Raman data indicate Be occupies Ga substitutional sites but Si atom is not substitutional. Si induces more As[sub Ga] in the layer. As As[sub Ga] increases, photoquenchable As[sub Ga] decreases. Fraction of photoquenchable defects correlates to defects within 3 nearest neighbor separations disrupting the metastability. Annealing reduces neutral As[sub Ga] content around 500C, similar to irradiation damaged and plastically deformed Ga[sub As], as opposed to bulk grown GaAs in which As[sub Ga]-related defects are stable up to 1100C. The lower temperature defect removal is due to V[sub Ga] enhanced diffusion of As[sub Ga] to As precipitates. The supersaturated V[sub GA] and also decreases during annealing. Annealing kinetics for As[sub Ga]-related defects gives 2.0 [plus minus] 0.3 eV and 1.5 [plus minus] 0.3 eV migration enthalpies for the As[sub Ga] and V[sub Ga]. This represents the difference between Ga and As atoms hopping into the vacancy. The non-photoquenchable As[sub Ga]-related defects anneal with an activation energy of 1.1 [plus minus] 0.3eV. Be acceptors can be activated by 800C annealing. Temperature difference between defect annealing and Be activation formation of As[sub Ga]-Be[sub Ga] pairs. Si donors can only be partially activated.

  15. Electron mobility enhancement in AlN/GaN/AlN heterostructures with InGaN nanogrooves

    E-Print Network [OSTI]

    it was discovered by Davydov et al.1 and con- firmed by independent studies2,3 that its band gap is small, EG InN =0 The conduction band offset at GaN/AlN interface was estimated as EQW=0.7 EG AlN -EG GaN =1918 meV. The nanoN/GaN/AlN QW. The depth of the nanogroove is calculated as E0=0.8 EG GaN -EG InxGa1-xN . The band gap of InxGa1

  16. Administration Office for Master Students

    E-Print Network [OSTI]

    Fischlin, Andreas

    Administration Office for Master Students in Environmental Sciences CHN H 50.4 CH - 8092 Zürich Tel to the Administration Office for Master Students at the beginning of the Master thesis Last name, first name and that the completed evaluation form is delivered to the student administration office within two weeks after

  17. UNIVERSITY OF YORK COMMUNICATIONS OFFICE

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    UNIVERSITY OF YORK COMMUNICATIONS OFFICE WEB OFFICE Web Strategy Date 4 February, 2003 Version 4, Press and PR Officer William Mackintosh, Web Manager #12;Web Strategy 4.4 ©University of York Page 2............................................................................................... 6 3.2 Objectives of the Web Strategy

  18. Development and Industrialization of InGaN/GaN LEDs on Patterned...

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

    epitaxial growth of indium gallium nitride (InGaN) layers capable of producing high-efficiency LEDs when combined with chip-on-board packaging techniques. The proposed...

  19. High-field quasi-ballistic transport in AlGaN/GaN heterostructures

    SciTech Connect (OSTI)

    Danilchenko, B. A.; Tripachko, N. A.; Belyaev, A. E.; Vitusevich, S. A. Hardtdegen, H.; Lüth, H.

    2014-02-17

    Mechanisms of electron transport formation in 2D conducting channels of AlGaN/GaN heterostructures in extremely high electric fields at 4.2?K have been studied. Devices with a narrow constriction for the current flow demonstrate high-speed electron transport with an electron velocity of 6.8?×?10{sup 7}?cm/s. Such a velocity is more than two times higher than values reported for conventional semiconductors and about 15% smaller than the limit value predicted for GaN. Superior velocity is attained in the channel with considerable carrier reduction. The effect is related to a carrier runaway phenomenon. The results are in good agreement with theoretical predictions for GaN-based materials.

  20. 2DEG electrodes for piezoelectric transduction of AlGaN/GaN MEMS resonators

    E-Print Network [OSTI]

    Weinstein, Dana

    A 2D electron gas (2DEG) interdigitated transducer (IDT) in Gallium Nitride (GaN) resonators is introduced and demonstrated. This metal-free transduction does not suffer from the loss mechanisms associated with more commonly ...

  1. Emission and Excitation Spectra of ZnO:Ga and ZnO:Ga,N Ceramics

    E-Print Network [OSTI]

    P. A. Rodnyi; I. V. Khodyuk; E. I. Gorokhova; S. B. Mikhrin; P. Dorenbos

    2010-09-07

    The spectral characteristics of ZnO:Ga and ZnO:Ga,N ceramics prepared by uniaxial hot pressing have been investigated. At room temperature, the edge (exciton) band at 3.12 eV dominates in the luminescence spectra of ZnO:Ga, while a wide luminescence band at 2.37 eV, which is likely to be due to zinc vacancies, is observed in the spectra of ZnO:Ga,N. Upon heating, the edge band maximum shifts to lower energies and the bandwidth increases. The extrapolated position of the edge-band maximum at zero temperature, Em(0) = 3.367 +/- 0.005 eV, is in agreement with the data for thin zinc oxide films. The luminescence excitation spectra in the range from 3 to 6.5 eV are reported and the mechanism of energy transfer to excitons and luminescence centers is considered.

  2. Composition profiling of GaAs/AlGaAs quantum dots grown by droplet epitaxy

    SciTech Connect (OSTI)

    Bocquel, J.; Koenraad, P. M. [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Giddings, A. D.; Prosa, T. J.; Larson, D. J. [CAMECA Instruments, Inc., 5500 Nobel Drive, Madison, Wisconsin 53711 (United States); Mano, T. [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan)

    2014-10-13

    Droplet epitaxy (DE) is a growth method which can create III-V quantum dots (QDs) whose optoelectronic properties can be accurately controlled through the crystallisation conditions. In this work, GaAs/AlGaAs DE-QDs have been analyzed with the complimentary techniques of cross-sectional scanning tunneling microscopy and atom probe tomography. Structural details and a quantitative chemical analysis of QDs of different sizes are obtained. Most QDs were found to be pure GaAs, while a small proportion exhibited high intermixing caused by a local etching process. Large QDs with a high aspect ratio were observed to have an Al-rich crown above the GaAs QD. This structure is attributed to differences in mobility of the cations during the capping phase of the DE growth.

  3. On strongly GA-convex functions and stochastic processes

    SciTech Connect (OSTI)

    Bekar, Nurgül Okur; Akdemir, Hande Günay; ??can, ?mdat

    2014-08-20

    In this study, we introduce strongly GA-convex functions and stochastic processes. We provide related well-known Kuhn type results and Hermite-Hadamard type inequality for strongly GA-convex functions and stochastic processes.

  4. Energy absorption in Ni-Mn-Ga/ polymer composites

    E-Print Network [OSTI]

    Feuchtwanger, Jorge

    2006-01-01

    In recent years Ni-Mn-Ga has attracted considerable attention as a new kind of actuator material. Off-stoichiometric single crystals of Ni2MnGa can regularly exhibit 6% strain in tetragonal martensites and orthorhombic ...

  5. InGaAs/GaAs (110) quantum dot formation via step meandering

    SciTech Connect (OSTI)

    Diez-Merino, Laura; Tejedor, Paloma

    2011-07-01

    InGaAs (110) semiconductor quantum dots (QDs) offer very promising prospects as a material base for a new generation of high-speed spintronic devices, such as single electron transistors for quantum computing. However, the spontaneous formation of InGaAs QDs is prevented by two-dimensional (2D) layer-by-layer growth on singular GaAs (110) substrates. In this work we have studied, by using atomic force microscopy and photoluminescence spectroscopy (PL), the growth of InGaAs/GaAs QDs on GaAs (110) stepped substrates by molecular beam epitaxy (MBE), and the modification of the adatom incorporation kinetics to surface steps in the presence of chemisorbed atomic hydrogen. The as-grown QDs exhibit lateral dimensions below 100 nm and emission peaks in the 1.35-1.37 eV range. It has been found that a step meandering instability derived from the preferential attachment of In adatoms to [110]-step edges relative to [11n]-type steps plays a key role in the destabilization of 2D growth that leads to 3D mound formation on both conventional and H-terminated vicinal substrates. In the latter case, the driving force for 3D growth via step meandering is enhanced by H-induced upward mass transport in addition to the lower energy cost associated with island formation on H-terminated substrates, which results in a high density array of InGaAs/GaAs dots selectively nucleated on the terrace apices with reduced lateral dimensions and improved PL efficiency relative to those of conventional MBE-grown samples.

  6. Sheet resistance under Ohmic contacts to AlGaN/GaN heterostructures

    SciTech Connect (OSTI)

    Haj?asz, M., E-mail: m.hajlasz@m2i.nl [Materials innovation institute (M2i), Mekelweg 2, 2628 CD, Delft (Netherlands); MESA Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE, Enschede (Netherlands); Donkers, J. J. T. M.; Sque, S. J.; Heil, S. B. S. [NXP Semiconductors Research, High Tech Campus 46, 5656 AE, Eindhoven (Netherlands); Gravesteijn, D. J. [NXP Semiconductors Research, High Tech Campus 46, 5656 AE, Eindhoven (Netherlands); MESA Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE, Enschede (Netherlands); Rietveld, F. J. R. [NXP Semiconductors, Gerstweg 2, 6534 AE, Nijmegen (Netherlands); Schmitz, J. [MESA Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE, Enschede (Netherlands)

    2014-06-16

    For the determination of specific contact resistance in semiconductor devices, it is usually assumed that the sheet resistance under the contact is identical to that between the contacts. This generally does not hold for contacts to AlGaN/GaN structures, where an effective doping under the contact is thought to come from reactions between the contact metals and the AlGaN/GaN. As a consequence, conventional extraction of the specific contact resistance and transfer length leads to erroneous results. In this Letter, the sheet resistance under gold-free Ti/Al-based Ohmic contacts to AlGaN/GaN heterostructures on Si substrates has been investigated by means of electrical measurements, transmission electron microscopy, and technology computer-aided design simulations. It was found to be significantly lower than that outside of the contact area; temperature-dependent electrical characterization showed that it exhibits semiconductor-like behavior. The increase in conduction is attributed to n-type activity of nitrogen vacancies in the AlGaN. They are thought to form during rapid thermal annealing of the metal stack when Ti extracts nitrogen from the underlying semiconductor. The high n-type doping in the region between the metal and the 2-dimensional electron gas pulls the conduction band towards the Fermi level and enhances horizontal electron transport in the AlGaN. Using this improved understanding of the properties of the material underneath the contact, accurate values of transfer length and specific contact resistance have been extracted.

  7. AlGaAs/GaAs photovoltaic converters for high power narrowband radiation

    SciTech Connect (OSTI)

    Khvostikov, Vladimir; Kalyuzhnyy, Nikolay; Mintairov, Sergey; Potapovich, Nataliia; Shvarts, Maxim; Sorokina, Svetlana; Andreev, Viacheslav; Luque, Antonio

    2014-09-26

    AlGaAs/GaAs-based laser power PV converters intended for operation with high-power (up to 100 W/cm{sup 2}) radiation were fabricated by LPE and MOCVD techniques. Monochromatic (? = 809 nm) conversion efficiency up to 60% was measured at cells with back surface field and low (x = 0.2) Al concentration 'window'. Modules with a voltage of 4 V and the efficiency of 56% were designed and fabricated.

  8. Guided Neuronal Growth on Arrays of Biofunctionalized GaAs/InGaAs Semiconductor Microtubes

    E-Print Network [OSTI]

    Cornelius S. Bausch; Aune Koitmäe; Eric Stava; Amanda Price; Pedro J. Resto; Yu Huang; David Sonnenberg; Yuliya Stark; Christian Heyn; Justin C. Williams; Erik W. Dent; Robert H. Blick

    2013-05-06

    We demonstrate embedded growth of cortical mouse neurons in dense arrays of semiconductor microtubes. The microtubes, fabricated from a strained GaAs/InGaAs heterostructure, guide axon growth through them and enable electrical and optical probing of propagating action potentials. The coaxial nature of the microtubes -- similar to myelin -- is expected to enhance the signal transduction along the axon. We present a technique of suppressing arsenic toxicity and prove the success of this technique by overgrowing neuronal mouse cells.

  9. Site Office Contracting Officer E-mail address Ames Site Office...

    National Nuclear Security Administration (NNSA)

    York Jacquelyn.york@ch.doe.gov Brookhaven Site Office Evelyn Landini Jennifer Hartmann elandini@bnl.gov jhartmann@bnl.gov Idaho Site Office Paul Allen allenph@id.doe.gov...

  10. Lateral and Vertical Transistors Using the AlGaN/GaN Heterostructure

    SciTech Connect (OSTI)

    Chowdhury, S; Mishra, UK

    2013-10-01

    Power conversion losses are endemic in all areas of electricity consumption, including motion control, lighting, air conditioning, and information technology. Si, the workhorse of the industry, has reached its material limits. Increasingly, the lateral AlGaN/GaN HEMT based on gallium nitride (GaN-on-Si) is becoming the device of choice for medium power electronics as it enables high-power conversion efficiency and reduced form factor at attractive pricing for wide market penetration. The reduced form factor enabled by high-efficiency operation at high frequency further enables significant system price reduction because of savings in bulky extensive passive elements and heat sink costs. The high-power market, however, still remains unaddressed by lateral GaN devices. The current and voltage demand for high power conversion application makes the chip area in a lateral topology so large that it becomes more difficult to manufacture. Vertical GaN devices would play a big role alongside of silicon carbide (SiC) to address the high power conversion needs. In this paper, the development, performance, and status of lateral and vertical GaN devices are discussed.

  11. GaNPAs Solar Cells Lattice-Matched To GaP: Preprint

    SciTech Connect (OSTI)

    Geisz, J. F.; Friedman, D. J.; Kurtz, S.

    2002-05-01

    This conference paper describes the III-V semiconductors grown on silicon substrates are very attractive for lower-cost, high-efficiency multijunction solar cells, but lattice-mismatched alloys that result in high dislocation densities have been unable to achieve satisfactory performance. GaNxP1-x-yAsy is a direct-gap III-V alloy that can be grown lattice-matched to Si when y= 4.7x - 0.1. We propose the use of lattice-matched GaNPAs on silicon for high-efficiency multijunction solar cells. We have grown GaNxP1-x-yAsy on GaP (with a similar lattice constant to silicon) by metal-organic chemical vapor phase epitaxy with direct band-gaps in the range of 1.5 to 2.0 eV. We demonstrate the performance of single-junction GaNxP1-x-yAsy solar cells grown on GaP substrates and discuss the prospects for the development of monolithic high-efficiency multijunction solar cells based on silicon substrates.

  12. Accurate characterization and improvement of GaAs microstrip attenuation 

    E-Print Network [OSTI]

    Carroll, James Mason

    1992-01-01

    Convergence. III. E. 6 Final Model. III. F Simulation Results for 100 um GaAs. . III. F. 1 On-GaAs Microstrip. III. I', 2 Suspended Microstrip Line . . . . 50 . . . . 51 . . . . 54 . . . . 56 . . . . 56 . . . 56 . . . . 64 64 . . . , 64 III. F. 3... Comparison Between On-GaAs and Suspcndcd Microstrip . . . 68 III. F. 4 Microstrip Inductance III. G EM Parameters in CAD Simulations . . III. H Simulation Results for 150 um GaAs. III. I Conclusions and Recommendations. IV RESEARCH ACCOMPLISHMENTS...

  13. Project Management Coordination Office Organization Chart

    Office of Energy Efficiency and Renewable Energy (EERE)

    Project Management Coordination Office Organization Chart, U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy.

  14. Welcome to The Office of Science

    ScienceCinema (OSTI)

    Brinkman, William

    2013-05-29

    The Director of the Department of Energy's Office of Science, Dr. William Brinkman, introduces the new Office of Science website.

  15. Categorical Exclusion Determinations: Office of Electricity Delivery...

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

    Office of Electricity Delivery and Energy Reliability Categorical Exclusion Determinations: Office of Electricity Delivery and Energy Reliability Categorical Exclusion...

  16. Advanced Manufacturing Office (Formerly Industrial Technologies...

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

    Manufacturing Office (Formerly Industrial Technologies Program) Advanced Manufacturing Office (Formerly Industrial Technologies Program) Presented at the NREL Hydrogen and Fuel...

  17. Advanced technologies for improving high frequency performance of AlGaN/GaN high electron mobility transistors

    E-Print Network [OSTI]

    Chung, Jinwook W. (Jinwook Will)

    2008-01-01

    In this thesis, we have used a combination of physical analysis, numerical simulation and experimental work to identify and overcome some of the main challenges in AlGaN/GaN high electron mobility transistors (HEMTs) for ...

  18. Office of the Director, NIH Director's Advisory

    E-Print Network [OSTI]

    Rau, Don C.

    Ethics Office (HNAT) Office of the Chief Information Officer (HNAV) Division of Resolution and Equity (2 Technology Policy and Review Office (2) Information Technology Acquisitions Services (4) Information of Communications and Outreach (3) Office of Research Information Systems (HNA36) Office of Policy for Extramural

  19. Office of Information Resources

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties -DepartmentAvailableHighOffice of Indian Energy Policy andSubpart

  20. Office of Inspector General

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterested Parties -DepartmentAvailableHighOffice of Indian Energy Policy

  1. A New Combustion Synthesis Method for GaN:Eu3+ and Ga2O3 :Eu3+

    E-Print Network [OSTI]

    McKittrick, Joanna

    A New Combustion Synthesis Method for GaN:Eu3+ and Ga2O3 :Eu3+ Luminescent Powders G. A. Hirata1 between the precursors. The preparation of Eu-doped Ga2O3 powders was achieved using a new combustion)3 and Ga(NO3)3 as the precursors and hydrazine as (non-carbonaceous) fuel. A spontaneous combustion

  2. Improved device performance of InAs/GaAs quantum dot solar cells with GaP strain compensation layers

    E-Print Network [OSTI]

    Jalali. Bahram

    Improved device performance of InAs/GaAs quantum dot solar cells with GaP strain compensation Center for High Technology Materials, University of New Mexico, 1313 Goddard SE, Albuquerque, New Mexico optical, electrical, and spectral response characteristics of three-stack InAs/GaAs quantum dot solar

  3. Lattice-Mismatched GaAs/InGaAs Two-Junction Solar Cells by Direct Wafer Bonding

    SciTech Connect (OSTI)

    Tanabe, K.; Aiken, D. J.; Wanlass, M. W.; Morral, A. F.; Atwater, H. A.

    2006-01-01

    Direct bonded interconnect between subcells of a lattice-mismatched III-V compound multijunction cell would enable dislocation-free active regions by confining the defect network needed for lattice mismatch accommodation to tunnel junction interfaces, while metamorphic growth inevitably results in less design flexibility and lower material quality than is desirable. The first direct-bond interconnected multijunction solar cell, a two-terminal monolithic GaAs/InGaAs two-junction solar cell, is reported and demonstrates viability of direct wafer bonding for solar cell applications. The tandem cell open-circuit voltage was approximately the sum of the subcell open-circuit voltages. This achievement shows direct bonding enables us to construct lattice-mismatched III-V multijunction solar cells and is extensible to an ultrahigh efficiency InGaP/GaAs/InGaAsP/InGaAs four-junction cell by bonding a GaAs-based lattice-matched InGaP/GaAs subcell and an InP-based lattice-matched InGaAsP/InGaAs subcell. The interfacial resistance experimentally obtained for bonded GaAs/InP smaller than 0.10 Ohm-cm{sup 2} would result in a negligible decrease in overall cell efficiency of {approx}0.02%, under 1-sun illumination.

  4. Atlanta Central UESC Pilot Project

    Energy Savers [EERE]

    Upgrade - VFD on Pumps 30,151 14 0 0 3,874 0 Heating System Upgrade - Replace Electric Boiler & Pumps 175,063 192 (6,087) 0 36,272 1,667 DDC Controls & Optimization 9,435 15...

  5. Properties of (Ga,Mn)As codoped with Li

    SciTech Connect (OSTI)

    Miyakozawa, Shohei; Chen, Lin; Matsukura, Fumihiro; Ohno, Hideo

    2014-06-02

    We grow Li codoped (Ga,Mn)As layers with nominal Mn composition up to 0.15 by molecular beam epitaxy. The layers before and after annealing are characterized by x-ray diffraction, transport, magnetization, and ferromagnetic resonance measurements. The codoping with Li reduces the lattice constant and electrical resistivity of (Ga,Mn)As after annealing. We find that (Ga,Mn)As:Li takes similar Curie temperature to that of (Ga,Mn)As, but with pronounced magnetic moments and in-plane magnetic anisotropy, indicating that the Li codoping has nontrivial effects on the magnetic properties of (Ga,Mn)As.

  6. 56 IEEE JOURNAL OF PHOTOVOLTAICS, VOL. 2, NO. 1, JANUARY 2012 Metamorphic GaAsP and InGaP Solar Cells on GaAs

    E-Print Network [OSTI]

    Haller, Gary L.

    solar cells are triple-junction concentrator devices, with each junction efficiently col- lecting subcell in a multijunction de- vice. GaAs0.66 P0.34 single-junction solar cells with Eg = 1.83 eV were56 IEEE JOURNAL OF PHOTOVOLTAICS, VOL. 2, NO. 1, JANUARY 2012 Metamorphic GaAsP and InGaP Solar

  7. Reactive codoping of GaAlInP compound semiconductors

    DOE Patents [OSTI]

    Hanna, Mark Cooper (Boulder, CO); Reedy, Robert (Golden, CO)

    2008-02-12

    A GaAlInP compound semiconductor and a method of producing a GaAlInP compound semiconductor are provided. The apparatus and method comprises a GaAs crystal substrate in a metal organic vapor deposition reactor. Al, Ga, In vapors are prepared by thermally decomposing organometallic compounds. P vapors are prepared by thermally decomposing phospine gas, group II vapors are prepared by thermally decomposing an organometallic group IIA or IIB compound. Group VIB vapors are prepared by thermally decomposing a gaseous compound of group VIB. The Al, Ga, In, P, group II, and group VIB vapors grow a GaAlInP crystal doped with group IIA or IIB and group VIB elements on the substrate wherein the group IIA or IIB and a group VIB vapors produced a codoped GaAlInP compound semiconductor with a group IIA or IIB element serving as a p-type dopant having low group II atomic diffusion.

  8. Office of Indian Energy Policy and Programs Office of Energy...

    Energy Savers [EERE]

    Indian Energy Policy and Programs Office of Energy Efficiency and Renewable Energy Tribal Energy Program Commercial-Scale Renewable Energy Project Development and Finance Workshop...

  9. Office of the Chief Financial Officer Annual Report 2010

    E-Print Network [OSTI]

    Fernandez, Jeffrey

    2011-01-01

    of Energy Efficiency and Renewable Energy (EERE) and non-DOEEnergy Efficiency and Renewable Energy (EERE) While OfficeEnergy Efficiency and Renewable Energy Assistant Secretary

  10. Three-junction solar cells comprised of a thin-film GaInP/GaAs tandem cell mechanically stacked on a Si cell

    SciTech Connect (OSTI)

    Yazawa, Y.; Tamura, K.; Watahiki, S.; Kitatani, T.; Ohtsuka, H.; Warabisako, T.

    1997-12-31

    Three-junction tandem solar cells were fabricated by mechanical stacking of a thin-film GaInP/GaAs monolithic tandem cell and a Si cell. The epitaxial lift-off (ELO) technique was used for the thinning of GaInP/GaAs tandem cells. Both spectral responses of the GaInP top cell and the GaAs middle cell in the thin-film GaInP/GaAs monolithic tandem cell were conserved. The Si cell performance has been improved by reducing the absorption loss in the GaAs substrate.

  11. Chemical beam epitaxy growth of AlGaAs/GaAs tunnel junctions using trimethyl aluminium for multijunction solar cells

    SciTech Connect (OSTI)

    Paquette, B.; DeVita, M.; Turala, A.; Kolhatkar, G.; Boucherif, A.; Jaouad, A.; Aimez, V.; Arès, R.; Wilkins, M.; Wheeldon, J. F.; Walker, A. W.; Hinzer, K.; Fafard, S.

    2013-09-27

    AlGaAs/GaAs tunnel junctions for use in high concentration multijunction solar cells were designed and grown by chemical beam epitaxy (CBE) using trimethyl aluminium (TMA) as the p-dopant source for the AlGaAs active layer. Controlled hole concentration up to 4?10{sup 20} cm{sup ?3} was achieved through variation in growth parameters. Fabricated tunnel junctions have a peak tunneling current up to 6140 A/cm{sup 2}. These are suitable for high concentration use and outperform GaAs/GaAs tunnel junctions.

  12. 0.7-eV GaInAs Junction for a GaInP/GaAs/GaInAs(1eV)/GaInAs(0.7eV) Four-Junction Solar Cell

    SciTech Connect (OSTI)

    Friedman, D. J.; Geisz, J. F.; Norman, A. G.; Wanlass, M. W.; Kurtz, S. R.

    2006-01-01

    We discuss recent developments in III-V multijunction solar cells, focusing on adding a fourth junction to the Ga{sub 0.5}In{sub 0.5} P/GaAs/Ga{sub 0.75}In{sub 0.25}As inverted three-junction cell. This cell, grown inverted on GaAs so that the lattice-mismatched Ga{sub 0.75}In{sub 0.25}As third junction is the last one grown, has demonstrated 38% efficiency, and 40% is likely in the near future. To achieve still further gains, a lower-bandgap Ga{sub x}In{sub 1-x}As fourth junction could be added to the three-junction structure for a four-junction cell whose efficiency could exceed 45% under concentration. Here, we present the initial development of the Ga{sub x}In{sub 1-x}As fourth junction. Junctions of various bandgaps ranging from 0.88 to 0.73 eV were grown, in order to study the effect of the different amounts of lattice mismatch. At a bandgap of 0.88 eV, junctions were obtained with very encouraging {approx}80% quantum efficiency, 57% fill factor, and 0.36 eV open-circuit voltage. The device performance degrades with decreasing bandgap (i.e., increasing lattice mismatch). We model the four-junction device efficiency vs. fourth junction bandgap to show that an 0.7-eV fourth-junction bandgap, while optimal if it could be achieved in practice, is not necessary; an 0.9-eV bandgap would still permit significant gains in multijunction cell efficiency while being easier to achieve than the lower-bandgap junction.

  13. OFFICE: NEPA REVIEWS:

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

    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 Natural GasAdjustmentsShirleyEnergyTher i nAand DOEDepartmentNew2008Group, Inc. Order(National4, 2014INFORMATION OFFICER

  14. Education Office Housing

    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 not find what you wereDisclaimersMailEconomicEducation Office

  15. Ames Site Office Jobs

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLosThe 26thI D- 6 0 4 2 rzNewsOffice of ScienceAdvancedU.S.

  16. Argonne Site Office Jobs

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLosThe 26thI D- 6 0 4 2 rzNewsOffice of

  17. In-Office Services:

    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 likeUniverseIMPACT EVALUATION PLAN FOR THE SITE-218 58ImprovingInaInstitute / TexasOffice

  18. Office Buildings - Energy Consumption

    U.S. Energy Information Administration (EIA) Indexed Site

    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 PageMonthly","10/2015"4,"Ames5 Tables July 1996 Energy Information Administration Office of Coal, Nuclear,DecadeYear Jan FebElements)Feet) Decade8

  19. Offices | Department of Energy

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

    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 Delicious Rank EERE: Alternative Fuels Data Center HomeVehicle Replacement U.S.Job&Energy Department »Offices

  20. Electron tunneling spectroscopy study of electrically active traps in AlGaN/GaN high electron mobility transistors

    SciTech Connect (OSTI)

    Yang, Jie Cui, Sharon; Ma, T. P.; Hung, Ting-Hsiang; Nath, Digbijoy; Krishnamoorthy, Sriram; Rajan, Siddharth

    2013-11-25

    We investigate the energy levels of electron traps in AlGaN/GaN high electron mobility transistors by the use of electron tunneling spectroscopy. Detailed analysis of a typical spectrum, obtained in a wide gate bias range and with both bias polarities, suggests the existence of electron traps both in the bulk of AlGaN and at the AlGaN/GaN interface. The energy levels of the electron traps have been determined to lie within a 0.5?eV band below the conduction band minimum of AlGaN, and there is strong evidence suggesting that these traps contribute to Frenkel-Poole conduction through the AlGaN barrier.

  1. A InGaN/GaN quantum dot green ({lambda}=524 nm) laser

    SciTech Connect (OSTI)

    Zhang Meng; Banerjee, Animesh; Lee, Chi-Sen; Hinckley, John M.; Bhattacharya, Pallab

    2011-05-30

    The characteristics of self-organized InGaN/GaN quantum dot lasers are reported. The laser heterostructures were grown on c-plane GaN substrates by plasma-assisted molecular beam epitaxy and the laser facets were formed by focused ion beam etching with gallium. Emission above threshold is characterized by a peak at 524 nm (green) and linewidth of 0.7 nm. The lowest measured threshold current density is 1.2 kA/cm{sup 2} at 278 K. The slope and wall plug efficiencies are 0.74 W/A and {approx}1.1%, respectively, at 1.3 kA/cm{sup 2}. The value of T{sub 0}=233 K in the temperature range of 260-300 K.

  2. Photocapacitance study of type-II GaSb/GaAs quantum ring solar cells

    SciTech Connect (OSTI)

    Wagener, M. C.; Botha, J. R.; Carrington, P. J.; Krier, A.

    2014-01-07

    In this study, the density of states associated with the localization of holes in GaSb/GaAs quantum rings are determined by the energy selective charging of the quantum ring distribution. The authors show, using conventional photocapacitance measurements, that the excess charge accumulated within the type-II nanostructures increases with increasing excitation energies for photon energies above 0.9?eV. Optical excitation between the localized hole states and the conduction band is therefore not limited to the ?(k?=?0) point, with pseudo-monochromatic light charging all states lying within the photon energy selected. The energy distribution of the quantum ring states could consequently be accurately related from the excitation dependence of the integrated photocapacitance. The resulting band of localized hole states is shown to be well described by a narrow distribution centered 407?meV above the GaAs valence band maximum.

  3. Efficiency enhancement of InGaN/GaN solar cells with nanostructures

    SciTech Connect (OSTI)

    Bai, J.; Yang, C. C.; Athanasiou, M.; Wang, T.

    2014-02-03

    We demonstrate InGaN/GaN multi-quantum-well solar cells with nanostructures operating at a wavelength of 520?nm. Nanostructures with a periodic nanorod or nanohole array are fabricated by means of modified nanosphere lithography. Under 1 sun air-mass 1.5 global spectrum illumination, a fill factor of 50 and an open circuit voltage of 1.9?V are achieved in spite of very high indium content in InGaN alloys usually causing degradation of crystal quality. Both the nanorod array and the nanohole array significantly improve the performance of solar cells, while a larger enhancement is observed for the nanohole array, where the conversion efficiency is enhanced by 51%.

  4. Graphene in ohmic contact for both n-GaN and p-GaN

    SciTech Connect (OSTI)

    Zhong, Haijian; Liu, Zhenghui; Shi, Lin; Xu, Gengzhao; Fan, Yingmin; Huang, Zengli [Suzhou Institute of Nano-Tech and Nano-Bionics, CAS, Suzhou 215123 (China); Wang, Jianfeng; Ren, Guoqiang; Xu, Ke, E-mail: kxu2006@sinano.ac.cn [Suzhou Institute of Nano-Tech and Nano-Bionics, CAS, Suzhou 215123 (China); Suzhou Nanowin Science and Technology Co., Ltd., Suzhou 215123 (China)

    2014-05-26

    The wrinkles of single layer graphene contacted with either n-GaN or p-GaN were found both forming ohmic contacts investigated by conductive atomic force microscopy. The local I–V results show that some of the graphene wrinkles act as high-conductive channels and exhibiting ohmic behaviors compared with the flat regions with Schottky characteristics. We have studied the effects of the graphene wrinkles using density-functional-theory calculations. It is found that the standing and folded wrinkles with zigzag or armchair directions have a tendency to decrease or increase the local work function, respectively, pushing the local Fermi level towards n- or p-type GaN and thus improving the transport properties. These results can benefit recent topical researches and applications for graphene as electrode material integrated in various semiconductor devices.

  5. Jefferson Lab Chief Operating Officer

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

    COO Privacy and Security Notice Skip over navigation Search the JLab Site Chief Operating Officer Please upgrade your browser. This site's design is only visible in a graphical...

  6. Profiles in garbage: Office paper

    SciTech Connect (OSTI)

    Miller, C. [Environmental Industry Associations, Washington, DC (United States)

    1998-04-01

    The primary markets for recycled office paper are tissue mills, printing and writing paper, and paperboard packaging. Other uses include exports and newsprint. As recently as 1990, more than half of recovered office paper was exported, primarily to paper mills in Pacific Rim countries. This decade has seen an increase in the number of mills using deinked market pulp made from office paper. North American capacity to produce deinked market pulp skyrocketed in the first half of this decade. However, oversupply in the end markets for office paper led to financial problems and shutdown for several of these new mills.

  7. Vehicle Technologies Office: Propulsion Systems

    Broader source: Energy.gov [DOE]

    Vehicle Technologies Office research focuses much of its effort on improving vehicle fuel economy while meeting increasingly stringent emissions standards. Achieving these goals requires a...

  8. Office of Secure Transportation Activities

    Office of Environmental Management (EM)

    6th, 2012 WIPP Knoxville, TN OFFICE OF SECURE TRANSPORTATION Agency Integration Briefing Our Mission To provide safe and secure ground and air transportation of nuclear weapons,...

  9. Director, Information Technology Services Office

    Broader source: Energy.gov [DOE]

    The mission of the information Technologies Services Office is to provide effective corporate management leadership to proactively identify and manage business system efficiency improvements and to...

  10. Director, Office of Resource Management

    Broader source: Energy.gov [DOE]

    The Office of the Associate Under Secretary for Environment, Health, Safety, and Security (AU) provides corporate leadership and strategic approaches for protecting DOEs workers, the public, the...

  11. Office of Science User Facilities

    Broader source: Energy.gov [DOE]

    This presentation summarizes the information on the Office of Science User Facilities, which was given during the webinar on the DOE BRIDGE funding opportunity.

  12. Temperature dependency of the emission properties from positioned In(Ga)As/GaAs quantum dots

    SciTech Connect (OSTI)

    Braun, T.; Schneider, C.; Maier, S.; Forchel, A.; Höfling, S.; Kamp, M.; Igusa, R.; Iwamoto, S.; Arakawa, Y.

    2014-09-15

    In this letter we study the influence of temperature and excitation power on the emission linewidth from site-controlled InGaAs/GaAs quantum dots grown on nanoholes defined by electron beam lithography and wet chemical etching. We identify thermal electron activation as well as direct exciton loss as the dominant intensity quenching channels. Additionally, we carefully analyze the effects of optical and acoustic phonons as well as close-by defects on the emission linewidth by means of temperature and power dependent micro-photoluminescence on single quantum dots with large pitches.

  13. Origins of ion irradiation-induced Ga nanoparticle motion on GaAs surfaces

    SciTech Connect (OSTI)

    Kang, M.; Wu, J. H.; Chen, H. Y.; Thornton, K.; Goldman, R. S. [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2136 (United States)] [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2136 (United States); Sofferman, D. L. [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2136 (United States) [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2136 (United States); Department of Physics, Adelphi University, Garden City, New York 11530-0701 (United States); Beskin, I. [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109-1040 (United States)] [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109-1040 (United States)

    2013-08-12

    We have examined the origins of ion irradiation-induced nanoparticle (NP) motion. Focused-ion-beam irradiation of GaAs surfaces induces random walks of Ga NPs, which are biased in the direction opposite to that of ion beam scanning. Although the instantaneous NP velocities are constant, the NP drift velocities are dependent on the off-normal irradiation angle, likely due to a difference in surface non-stoichiometry induced by the irradiation angle dependence of the sputtering yield. It is hypothesized that the random walks are initiated by ion irradiation-induced thermal fluctuations, with biasing driven by anisotropic mass transport.

  14. GaN based nanorods for solid state lighting

    SciTech Connect (OSTI)

    Li Shunfeng; Waag, Andreas [Institute of Semiconductor Technology, Braunschweig University of Technology, 38106 Braunschweig (Germany)

    2012-04-01

    In recent years, GaN nanorods are emerging as a very promising novel route toward devices for nano-optoelectronics and nano-photonics. In particular, core-shell light emitting devices are thought to be a breakthrough development in solid state lighting, nanorod based LEDs have many potential advantages as compared to their 2 D thin film counterparts. In this paper, we review the recent developments of GaN nanorod growth, characterization, and related device applications based on GaN nanorods. The initial work on GaN nanorod growth focused on catalyst-assisted and catalyst-free statistical growth. The growth condition and growth mechanisms were extensively investigated and discussed. Doping of GaN nanorods, especially p-doping, was found to significantly influence the morphology of GaN nanorods. The large surface of 3 D GaN nanorods induces new optical and electrical properties, which normally can be neglected in layered structures. Recently, more controlled selective area growth of GaN nanorods was realized using patterned substrates both by metalorganic chemical vapor deposition (MOCVD) and by molecular beam epitaxy (MBE). Advanced structures, for example, photonic crystals and DBRs are meanwhile integrated in GaN nanorod structures. Based on the work of growth and characterization of GaN nanorods, GaN nanoLEDs were reported by several groups with different growth and processing methods. Core/shell nanoLED structures were also demonstrated, which could be potentially useful for future high efficient LED structures. In this paper, we will discuss recent developments in GaN nanorod technology, focusing on the potential advantages, but also discussing problems and open questions, which may impose obstacles during the future development of a GaN nanorod based LED technology.

  15. February 2008 Office of Chief Financial Officer Department of Energy

    E-Print Network [OSTI]

    February 2008 Office of Chief Financial Officer Department of Energy FY 2009 Congressional Budget Department of Energy FY 2009 Congressional Budget Request Volume 4 DOE/CF-027 Volume 4 Science Printed with soy ink on recycled paper #12;#12;Department of Energy/ Science FY 2009 Congressional Budget Volume 4

  16. EXECUTIVE OFFICE OF THE PRESIDENT OFFICE OF MANAGEMENT AND BUDGET

    E-Print Network [OSTI]

    US Army Corps of Engineers

    and quality. VE contributes to the overall management objectives of streamlining operations, improving qualityEXECUTIVE OFFICE OF THE PRESIDENT OFFICE OF MANAGEMENT AND BUDGET WASHINGTON, D.C. 20503 December, improve performance, enhance quality, and foster the use of innovation. Agencies should maintain policies

  17. OFFICE OF GRADUATE AND PROFESSIONAL STUDIES Thesis Office

    E-Print Network [OSTI]

    OFFICE OF GRADUATE AND PROFESSIONAL STUDIES Thesis Office 612 Sterling Evans Library rev. 6/2013 thesis@tamu.edu 5000 TAMU Tel. 979.845.2225 Fax 979.862.3124 College Station, TX 77843-5000 Page 1 of 1 http://thesis.tamu.edu GUIDELINES FOR THE PREPARATION OF THE APPROVAL OF WRITTEN THESIS FORM

  18. Education Officers in PSOM Departments Education Officer Phone Email

    E-Print Network [OSTI]

    Sharp, Kim

    Education Officers in PSOM Departments Education Officer Phone Email Anesthesiology and Critical@upenn.edu Cell & Developmental Biology Neal A. Rubinstein, MD, PhD 898-4162 nrubinst@mail.med.upenn.edu Psychiatry Anthony Rostain, MD 746-7210 rostain@mail.med.upenn.edu Radiation Oncology Sydney Evans, VMD 898

  19. UNLV OFFICE OF INFORMATION TECHNOLOGY PASSWORD POLICY

    E-Print Network [OSTI]

    Walker, Lawrence R.

    UNLV OFFICE OF INFORMATION TECHNOLOGY PASSWORD POLICY RESPONSIBLE ADMINISTRATOR: VICE PROVOST FOR INFORMATION TECHNOLOGY RESPONSIBLE OFFICE(S): OFFICE OF THE VICE PROVOST FOR INFORMAnON TECHNOLOGY ORIGINALLY to the Office of Information Technology's Policies and Procedures web page at http

  20. ORP Vendor Contact List MetLife Resources

    E-Print Network [OSTI]

    Almor, Amit

    Bldg 600, Ste 1400 Atlanta, GA 30328 770- 407-2424 (Office) 770-407-2428 (Fax) http://www.metlife.com/scorp The Hartford Marc Reicheg Sr. Regional Manager Client Care Group P.O. Box 1583 Hartford, CT 06144 888-89SCORP@tiaa-cref.org http://www.tiaa-cref.org/scorp VALIC Mandy Yelton SC District Administrative Assistant 3710 Landmark Dr

  1. Advanced Oxidation Technology for Pulp Mill Effluent 

    E-Print Network [OSTI]

    Hart, J. R.

    1992-01-01

    TECHNOLOGY FOR PULP MILL EFFLUENT J. ROBERT HART, MANAGER, EPRI PULP & PAPER OFFICE, ATLANTA, GA ABSTRACT The composition of effluent from various pulping processes can exhibit a wide range of physical and chemical parameters. The dissolved solids... and had the necessary accessories to monitor gas and liquid flows, injection and sampling points, and off-gas detection. The ozone was generated with a Griffin Technics HC-l.O ozone generator. This unit is air-cooled and contains two dielectrics...

  2. J. Douglas Streit, Information Security Officer Office of Computing and Communications Services

    E-Print Network [OSTI]

    J. Douglas Streit, Information Security Officer Office of Computing and Communications Services Last updated February 6, 2012 Old Dominion University Information Technology Security Program #12;J. Douglas Streit, Information Security Officer Office of Computing and Communications Services Last updated

  3. Science Highlights | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Agency - Energy (ARPA-E) Office of Environmental Management (EM) Office of Energy Efficiency and Renewable Energy (EERE) Office of Fossil Energy (FE) Office of Nuclear Energy...

  4. 2014 Annual Planning Summary for the Richland Operations Office...

    Energy Savers [EERE]

    Richland Operations Office and the Office of River Protection 2014 Annual Planning Summary for the Richland Operations Office and the Office of River Protection The ongoing and...

  5. GaInP/GaAs dual junction solar cells on Ge/Si epitaxial templates Melissa J. Archer,1,a

    E-Print Network [OSTI]

    Atwater, Harry

    GaInP/GaAs dual junction solar cells on Ge/Si epitaxial templates Melissa J. Archer,1,a Daniel C, crack-free GaInP/GaAs double junction solar cells were grown by metal organic chemical vapor deposition with the world record efficiency is a metamorphic triple junction GaInP/GaAs/Ge cell.6 Alternatively, wafer

  6. Enhanced hole transport in InGaN/GaN multiple quantum well light-emitting

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    -emitting diodes (LEDs) are considered the new generation lighting sources due to their advantages in power Society of America OCIS codes: 230.3670, 230.5590, 160.6000. Nitride-based high-power light devoted to the development of high-brightness GaN-based LEDs [3­5]. Lateral hole spreading is one

  7. High-Efficiency GaInP/GaAs Tandem Solar Cells

    SciTech Connect (OSTI)

    Bertness, K. A.; Friedman, D. J.; Kurtz, S. R.; Kibbler, A. E.; Cramer, C.; Olson, J. M.

    1996-09-01

    GaInP/GaAs tandem solar cells have achieved efficiencies between 25.7-30.2%, depending on illumination conditions. The efficiencies are the highest confirmed two-terminal values measured for any solar cell within each standard illumination category. The monolithic, series-connected design of the tandem cells allows them to be substituted for silicon or gallium arsenide cells in photovoltaic panel systems with minimal design changes. The advantages of using GaInP/GaAs tandem solar cells in space and terrestrial applications are discussed primarily in terms of the reduction in balance-of-system costs that accrues when using a higher efficiency cell. The new efficiency values represent a significant improvement over previous efficiencies for this materials system, and we identify grid design, back interface passivation, and top interface passivation as the three key factors leading to this improvement. In producing the high-efficiency cells, we have addressed nondestructive diagnostics and materials growth reproducibility as well as peak cell performance.

  8. High-efficiency GaInP/GaAs tandem solar cells

    SciTech Connect (OSTI)

    Bertness, K.A.; Friedman, D.J.; Kurtz, S.R.; Kibbler, A.E.; Kramer, C.; Olson, J.M.

    1994-12-01

    GaInP/GaAs tandem solar cells have achieved new record efficiencies, specifically 25.7% under air-mass 0 (AM0) illumination, 29.5% under AM 1.5 global (AM1.5G) illumination, and 30.2% at 140-180x concentration under AM 1.5 direct (AM1.5D) illumination. These values are the highest two-terminal efficiencies achieved by any solar cell under these illumination conditions. The monolithic, series-connected design of the tandem cells allows them to be substituted for silicon or gallium arsenide cells in photovoltaic panel systems with minimal design changes. The advantages of using GaInP/GaAs tandem solar cells in space and terrestrial applications are discussed primarily in terms of the reduction in balance-of-system costs that accrues when using a higher efficiency cell. The new efficiency values represent a significant improvement over previous efficiencies for this materials system, and we identify grid design, back interface passivation, and top interface passivation as the three key factors leading to this improvement. In producing the high-efficiency cells, we have addressed nondestructive diagnostics and materials growth reproducibility as well as peak cell performance. 31 refs.

  9. TJ Solar Cell (GaInP/GaAs/Ge Ultrahigh-Efficiency Solar Cells

    SciTech Connect (OSTI)

    Friedman, Daniel

    2002-04-17

    This talk will discuss recent developments in III-V multijunction photovoltaic technology which have led to the highest-efficiency solar cells ever demonstrated. The relationship between the materials science of III-V semiconductors and the achievement of record solar cell efficiencies will be emphasized. For instance, epitaxially-grown GAInP has been found to form a spontaneously-ordered GaP/InP (111) superlattice. This ordering affects the band gap of the material, which in turn affects the design of solar cells which incorporate GaInP. For the next generation of ultrahigh-efficiency III-V solar cells, we need a new semiconductor which is lattice-matched to GaAs, has a band gap of 1 eV, and has long minority-carrier diffusion lengths. Out of a number of candidate materials, the recently-discovered alloy GaInNAs appears to have the greatest promise. This material satisfies the first two criteria, but has to date shown very low diffusion lengths, a problem which is our current focus in the development of these next-generation cells.

  10. Multijunction GaInP/GaInAs/Ge solar cells with Bragg reflectors

    SciTech Connect (OSTI)

    Emelyanov, V. M. Kalyuzhniy, N. A.; Mintairov, S. A.; Shvarts, M. Z.; Lantratov, V. M.

    2010-12-15

    Effect of subcell parameters on the efficiency of GaInP/Ga(In)As/Ge tandem solar cells irradiated with 1-MeV electrons at fluences of up to 3 x 10{sup 15} cm{sup -2} has been theoretically studied. The optimal thicknesses of GaInP and GaInAs subcells, which provide the best photocurrent matching at various irradiation doses in solar cells with and without built-in Bragg reflectors, were determined. The dependences of the photoconverter efficiency on the fluence of 1-MeV electrons and on the time of residence in the geostationary orbit were calculated for structures optimized to the beginning and end of their service lives. It is shown that the optimization of the subcell heterostructures for a rated irradiation dose and the introduction of Bragg reflectors into the structure provide a 5% overall increase in efficiency for solar cells operating in the orbit compared with unoptimized cells having no Bragg reflector.

  11. Localized corrosion of GaAs surfaces and formation of porous GaAs

    SciTech Connect (OSTI)

    Schmuki, P.; Vitus, C.M.; Isaacs, H.S.; Fraser, J.; Graham, M.J.

    1995-12-01

    The present work deals with pitting corrosion of p- and n-type GaAs (100). Pit growth can be electrochemically initiated on both conduction types in chloride-containing solutions and leads after extended periods of time to the formation of a porous GaAs structure. In the case of p-type material, localized corrosion is only observed if a passivating film is present on the surface, otherwise -- e.g. in acidic solutions -- the material suffers from a uniform attack (electropolishing) which is independent of the anion present. In contrast, pitting corrosion of n-type material can be triggered independent of the presence of an oxide film. This is explained in terms of the different current limiting factor for the differently doped materials (oxide film in the case of the p- and a space charge layer in the case of the n-GaAs). The porous structure was characterized by SEM, EDX and AES, and consists mainly of GaAs. From scratch experiments it is clear that the pit initiation process is strongly influenced by surface defects. For n-type material, AFM investigations show that light induced roughening of the order of several hundred nm occurs under non-passivating conditions. This nm- scale roughening however does not affect the pitting process.

  12. OFFICE OF SUSTAINABILITY Community Forum

    E-Print Network [OSTI]

    van den Berg, Jur

    Travel Natural Gas Transportation Electricity Without reductions 2007 2025 2050 Emissions (MTCO2e immediate steps to reduce greenhouse gas emissions · Create Sustainability Office and oversight committees RENEWABLES GROUNDS FOOD WASTE COMMUNICATION #12;OFFICE OF SUSTAINABILITY Open house meetings 3 Targeted

  13. Administration Office for Master Students

    E-Print Network [OSTI]

    Fischlin, Andreas

    of the thesis to the Administration Office for Master Students. With the agreement of the main supervisorAdministration Office for Master Students in Environmental Sciences CHN H 50.4 CH - 8092 Zürich Tel. +41-44-632 58 90 env_master@usys.ethz.ch Master Thesis Evaluation Form has to be sent

  14. Julia Maddock Senior Press Officer

    E-Print Network [OSTI]

    Julia Maddock Senior Press Officer #12;Corporate Planning and Communication Directorate Staff 31 Relations : Peter Barratt Press Officers : Gill Ormrod (until end December) Julia Maddock Natalie Bealing;Channel Activities · Media Relations Press Releases (Database + AlphaGalileo/Eurekalert/AAAS) Journalist

  15. Richland Operations Office technology summary

    SciTech Connect (OSTI)

    Not Available

    1994-05-01

    This document has been prepared by the Department of Energy`s Environmental Management Office of Technology Development to highlight its research, development, demonstration, testing, and evaluation activities funded through the Richland Operations Office. Technologies and processes described have the potential to enhance cleanup and waste management efforts.

  16. OKLAHOMA STATE UNIVERSITY BURSAR'S OFFICE

    E-Print Network [OSTI]

    Veiga, Pedro Manuel Barbosa

    OKLAHOMA STATE UNIVERSITY BURSAR'S OFFICE RESTRICTED TITLE IV FUND PAYMENT Valid through July 31st, return form to: Oklahoma State University Office of the Bursar 113 Student Union Building Stillwater, Oklahoma 74078 Your authorization may be rescinded at any time by sending a written cancellation request

  17. OKLAHOMA STATE UNIVERSITY BURSAR'S OFFICE

    E-Print Network [OSTI]

    Veiga, Pedro Manuel Barbosa

    OKLAHOMA STATE UNIVERSITY BURSAR'S OFFICE RESTRICTED PLUS LOAN PAYMENT Valid through July 31st, return form to: Oklahoma State University Office of the Bursar 113 Student Union Building Stillwater, Oklahoma 74078 Your authorization may be rescinded at any time by sending a written cancellation request

  18. Demonstration of a semipolar (10(1)over-bar(3)over-bar) InGaN/GaN green light emitting diode

    E-Print Network [OSTI]

    2005-01-01

    InGaN / GaN green light emitting diode R. Sharma, a? P. M.green ??525 nm? light emitting diode ?LED?. The fabricated

  19. Inverse spin Hall effect in Pt/(Ga,Mn)As

    SciTech Connect (OSTI)

    Nakayama, H.; Chen, L.; Chang, H. W.; Ohno, H.; Matsukura, F.

    2015-06-01

    We investigate dc voltages under ferromagnetic resonance in a Pt/(Ga,Mn)As bilayer structure. A part of the observed dc voltage is shown to originate from the inverse spin Hall effect. The sign of the inverse spin Hall voltage is the same as that in Py/Pt bilayer structure, even though the stacking order of ferromagnetic and nonmagnetic layers is opposite to each other. The spin mixing conductance at the Pt/(Ga,Mn)As interface is determined to be of the order of 10{sup 19?}m{sup ?2}, which is about ten times greater than that of (Ga,Mn)As/p-GaAs.

  20. THE UNIVERSITY OF UTAH OFFICE OF SUSTAINABILITY

    E-Print Network [OSTI]

    Feschotte, Cedric

    THE UNIVERSITY OF UTAH OFFICE OF SUSTAINABILITY THE UNIVERSITY OF UTAH OFFICE OF SUSTAINABILITY THE UNIVERSITY OF UTAH OFFICE OF SUSTAINABILITY GREENERGREENERGREENERGREENERGREENERGREENERGREENERGREENERGREENERGREENERGREENERGREENERFall 2010 - Spring 2011 GREENERGREENERGREENERGREENERGREENERGREENER Working for a Sustainable Campus

  1. Office of Technology Transfer Material Transfer Agreements

    E-Print Network [OSTI]

    Tullos, Desiree

    Office of Technology Transfer · Material Transfer Agreements · Confidentiality Agreements · Copyright / Patent Licensing The Office of Technology Transfer facilitates the transfer of innovations out of the university for public benefit TOOLS #12;Office of Technology Transfer Facilitating transfer of innovations

  2. 4-H Club Officer Handbook - Reporter 

    E-Print Network [OSTI]

    Howard, Jeff W.

    2006-08-09

    This section from the 4-H Club Officer Handbook features the multi-faceted role of the Reporter/Public Relations Officer. Tips on covering the news and dealing with your local media are essential to the officer's success ...

  3. Deep level defects in n-type GaAsBi and GaAs grown at low temperatures

    SciTech Connect (OSTI)

    Mooney, P. M.; Watkins, K. P.; Jiang, Zenan; Basile, A. F.; Lewis, R. B.; Bahrami-Yekta, V.; Masnadi-Shirazi, M.; Beaton, D. A.; Tiedje, T.

    2013-04-07

    Deep level defects in n-type GaAs{sub 1-x}Bi{sub x} having 0 < x < 0.012 and GaAs grown by molecular beam epitaxy (MBE) at substrate temperatures between 300 and 400 Degree-Sign C have been investigated by Deep Level Capacitance Spectroscopy. Incorporating Bi suppresses the formation of an electron trap with activation energy 0.40 eV, thus reducing the total trap concentration in dilute GaAsBi layers by more than a factor of 20 compared to GaAs grown under the same conditions. We find that the dominant traps in dilute GaAsBi layers are defect complexes involving As{sub Ga}, as expected for MBE growth at these temperatures.

  4. High efficiency InGaN/GaN light emitting diodes with asymmetric triangular multiple quantum wells

    SciTech Connect (OSTI)

    Chang, Chiao-Yun; Li, Hen; Lu, Tien-Chang, E-mail: timtclu@mail.nctu.edu.tw [Department of Photonics and Institute of Electro-Optical Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan 300 (China)

    2014-03-03

    In this study, we demonstrated high efficiency InGaN/GaN light emitting diodes (LEDs) with asymmetric triangular multiple quantum wells (MQWs). Asymmetric triangular MQWs not only contribute to uniform carrier distribution in InGaN/GaN MQWs but also yield a low Auger recombination rate. In addition, asymmetric triangular MQWs with gallium face-oriented inclination band profiles can be immune from the polarization charge originating from typical c-plane InGaN/GaN quantum well structures. In the experiment, LEDs incorporated with asymmetric triangular MQWs with gallium face-oriented inclination band profiles exhibited a 60.0% external quantum efficiency at 20?mA and a 27.0% efficiency droop at 100?mA (corresponding to a current density of 69?A/cm{sup 2}), which accounted for an 11.7% efficiency improvement and a 31.1% droop reduction compared with symmetric square quantum well structure LEDs.

  5. Deep level centers and their role in photoconductivity transients of InGaAs/GaAs quantum dot chains

    SciTech Connect (OSTI)

    Kondratenko, S. V. Vakulenko, O. V.; Mazur, Yu. I. Dorogan, V. G.; Marega, E.; Benamara, M.; Ware, M. E.; Salamo, G. J.

    2014-11-21

    The in-plane photoconductivity and photoluminescence are investigated in quantum dot-chain InGaAs/GaAs heterostructures. Different photoconductivity transients resulting from spectrally selecting photoexcitation of InGaAs QDs, GaAs spacers, or EL2 centers were observed. Persistent photoconductivity was observed at 80?K after excitation of electron-hole pairs due to interband transitions in both the InGaAs QDs and the GaAs matrix. Giant optically induced quenching of in-plane conductivity driven by recharging of EL2 centers is observed in the spectral range from 0.83?eV to 1.0?eV. Conductivity loss under photoexcitation is discussed in terms of carrier localization by analogy with carrier distribution in disordered media.

  6. Au impact on GaAs epitaxial growth on GaAs (111){sub B} substrates in molecular beam epitaxy

    SciTech Connect (OSTI)

    Liao, Zhi-Ming; Chen, Zhi-Gang; Xu, Hong-Yi; Guo, Ya-Nan; Sun, Wen; Zhang, Zhi; Yang, Lei; Lu, Zhen-Yu; Chen, Ping-Ping; Lu, Wei; Zou, Jin; Centre for Microscopy and Microanalysis, The University of Queensland, St. Lucia, Queensland 4072

    2013-02-11

    GaAs growth behaviour under the presence of Au nanoparticles on GaAs {l_brace}111{r_brace}{sub B} substrate is investigated using electron microscopy. It has been found that, during annealing, enhanced Ga surface diffusion towards Au nanoparticles leads to the GaAs epitaxial growth into {l_brace}113{r_brace}{sub B} faceted triangular pyramids under Au nanoparticles, governed by the thermodynamic growth, while during conventional GaAs growth, growth kinetics dominates, resulting in the flatted triangular pyramids at high temperature and the epitaxial nanowires growth at relatively low temperature. This study provides an insight of Au nanoparticle impact on GaAs growth, which is critical for understanding the formation mechanisms of semiconductor nanowires.

  7. Office of the Chief Information Officer | Department of Energy

    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 NewsInformationJesseworkSURVEY UNIVERSEHowScientific andComplexOffice ofOffice|Office

  8. Office of the Chief Human Capital Officer | Department of Energy

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

    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 Delicious Rank EERE: Alternative Fuels Data CenterFinancialInvesting inServices » NEPANewsOffice ofOffice ofOffice of

  9. An inverted AlGaAs/GaAs patterned-Ge tunnel junction cascade concentrator solar cell

    SciTech Connect (OSTI)

    Venkatasubramanian, R. )

    1993-01-01

    This report describes work to develop inverted-grown Al[sub 0.34]Ga[sub 0.66]As/GaAs cascades. Several significant developments are reported on as follows: (1) The AM1.5 1-sun total-area efficiency of the top Al[sub 0.34]Ga[sub 0.66]As cell for the cascade was improved from 11.3% to 13.2% (NREL measurement [total-area]). (2) The cycled'' organometallic vapor phase epitaxy growth (OMVPE) was studied in detail utilizing a combination of characterization techniques including Hall-data, photoluminescence, and secondary ion mass spectroscopy. (3) A technique called eutectic-metal-bonding (EMB) was developed by strain-free mounting of thin GaAs-AlGaAs films (based on lattice-matched growth on Ge substrates and selective plasma etching of Ge substrates) onto Si carrier substrates. Minority-carrier lifetime in an EMB GaAs double-heterostructure was measured as high as 103 nsec, the highest lifetime report for a freestanding GaAs thin film. (4) A thin-film, inverted-grown GaAs cell with a 1-sun AM1.5 active-area efficiency of 20.3% was obtained. This cell was eutectic-metal-bonded onto Si. (5) A thin-film inverted-grown, Al[sub 0.34]Ga[sub 0.66]As/GaAs cascade with AM1.5 efficiency of 19.9% and 21% at 1-sun and 7-suns, respectively, was obtained. This represents an important milestone in the development of an AlGaAs/GaAs cascade by OMVPE utilizing a tunnel interconnect and demonstrates a proof-of-concept for the inverted-growth approach.

  10. The Energy Department's Geothermal Technologies Office Releases...

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

    The Energy Department's Geothermal Technologies Office Releases 2013 Annual Report The Energy Department's Geothermal Technologies Office Releases 2013 Annual Report February 7,...

  11. Geothermal Technologies Office 2015 Peer Review

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

    | US DOE Geothermal Office eere.energy.gov Geothermal Technologies Office 2015 Peer Review Sustainability of Shear-Induced Permeability for EGS Reservoirs - A Laboratory...

  12. Daniel Lee Cloyd named Counterintelligence Office

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

    FBI officer accepts LANL counterintelligence post November 10, 2010 Daniel Lee Cloyd named Counterintelligence Office leader LOS ALAMOS, New Mexico, November 10, 2010-Daniel Lee...

  13. Vehicle Technologies Office: 2014 Electric Drive Technologies...

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

    Vehicle Technologies Office: 2014 Electric Drive Technologies Annual Progress Report Vehicle Technologies Office: 2014 Electric Drive Technologies Annual Progress Report The...

  14. Innovative Office Lighting System with Integrated Spectrally...

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

    an innovative LED office lighting system solution that integrates light delivery, optics, and controls for energy efficiency and occupant health and well-being. The office...

  15. Vehicle Technologies Office: AVTA - Evaluating National Parks...

    Energy Savers [EERE]

    Office: AVTA - Evaluating National Parks and Forest Service Fleets for Plug-in Electric Vehicles Vehicle Technologies Office: AVTA - Evaluating National Parks and Forest...

  16. Vehicle Technologies Office Merit Review 2014: Understanding...

    Energy Savers [EERE]

    Vehicle Technologies Office Merit Review 2014: Understanding Protective Film Formation on Magnesium Alloys in Automotive Applications Vehicle Technologies Office Merit Review 2014:...

  17. Native American Finance Officers Association Conference | Department...

    Office of Environmental Management (EM)

    Native American Finance Officers Association Conference Native American Finance Officers Association Conference March 5, 2012 - 5:50pm Addthis This event will take place on March...

  18. DOL: Office of the Ombudsman for EEOICPA

    Broader source: Energy.gov [DOE]

    The Office of the Ombudsman for the Energy Employees Occupational Illness Compensation Program is an independent office within the Department of Labor that provides assistance and information to...

  19. Independent Oversight Review, Savannah River Operations Office...

    Office of Environmental Management (EM)

    Savannah River Operations Office - July 2013 Independent Oversight Review, Savannah River Operations Office - July 2013 July 2013 Review of the Employee Concerns Program at the...

  20. Quality New Mexico recognizes Community Programs Office

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

    Quality New Mexico recognizes Community Programs Office March 6, 2012 LOS ALAMOS, New Mexico, March 6, 2012-Los Alamos National Laboratory's Community Programs Office received...

  1. ORISE Resources: Medical Office Preparedness Planner

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

    partnership with CDC yields Medical Office Preparedness Planner for Primary Care Providers The Medical Office Preparedness Planner is a tool for primary care providers (PCPs) and...

  2. Project Management Coordination Office Organization Chart | Department...

    Office of Environmental Management (EM)

    Office Organization Chart, U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy. pmeorgchart101013.pdf More Documents & Publications Management Reform...

  3. Office of Security Assessments | Department of Energy

    Energy Savers [EERE]

    Security Assessments Office of Security Assessments MISSION The Office of Security Assessments is responsible for the independent evaluation of the effectiveness of safeguards and...

  4. DC characteristics of OMVPE-grown N-p-n InGaP/InGaAsN DHBTs

    SciTech Connect (OSTI)

    Li, N.Y.; Chang, P.C.; Baca, A.G.; Xie, X.M.; Sharps, P.R.; Hou, H.Q.

    2000-01-04

    The authors demonstrate, for the first time, a functional N-p-n heterojunction bipolar transistor using a novel material, InGaAsN, with a bandgap energy of 1.2eV as the p-type base layer. A 300{angstrom}-thick In{sub x}Ga{sub 1-x}As graded layer was introduced to reduce the conduction band offset at the p-type InGaAsN base and n-type GaAs collector junction. For an emitter size of 500 {mu}m{sup 2}, a peak current gain of 5.3 has been achieved.

  5. The Effect of the Thermal Boundary Resistance on Self-Heating of AlGaN/GaN HFETs

    E-Print Network [OSTI]

    sound velocity in GaN. The cut off wave vector is given by where NA is the Avogadro number, is the mass

  6. Reliability of AlGaN/GaN high electron mobility transistors on low dislocation density bulk GaN substrate: Implications of surface step edges

    SciTech Connect (OSTI)

    Killat, N., E-mail: Nicole.Killat@bristol.ac.uk, E-mail: Martin.Kuball@bristol.ac.uk; Montes Bajo, M.; Kuball, M., E-mail: Nicole.Killat@bristol.ac.uk, E-mail: Martin.Kuball@bristol.ac.uk [Center for Device Thermography and Reliability (CDTR), H.H. Wills Physics Laboratory, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Paskova, T. [Kyma Technologies, Inc., Raleigh, North Carolina 27617 (United States) [Kyma Technologies, Inc., Raleigh, North Carolina 27617 (United States); Materials Science and Engineering Department, North Carolina State University, Raleigh, North Carolina 27695 (United States); Evans, K. R. [Kyma Technologies, Inc., Raleigh, North Carolina 27617 (United States)] [Kyma Technologies, Inc., Raleigh, North Carolina 27617 (United States); Leach, J. [Kyma Technologies, Inc., Raleigh, North Carolina 27617 (United States) [Kyma Technologies, Inc., Raleigh, North Carolina 27617 (United States); Electrical and Computer Engineering Department, Virginia Commonwealth University, Richmond, Virginia 23284 (United States); Li, X.; Özgür, Ü.; Morkoç, H. [Electrical and Computer Engineering Department, Virginia Commonwealth University, Richmond, Virginia 23284 (United States)] [Electrical and Computer Engineering Department, Virginia Commonwealth University, Richmond, Virginia 23284 (United States); Chabak, K. D.; Crespo, A.; Gillespie, J. K.; Fitch, R.; Kossler, M.; Walker, D. E.; Trejo, M.; Via, G. D.; Blevins, J. D. [Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio 45433 (United States)] [Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio 45433 (United States)

    2013-11-04

    To enable gaining insight into degradation mechanisms of AlGaN/GaN high electron mobility transistors, devices grown on a low-dislocation-density bulk-GaN substrate were studied. Gate leakage current and electroluminescence (EL) monitoring revealed a progressive appearance of EL spots during off-state stress which signify the generation of gate current leakage paths. Atomic force microscopy evidenced the formation of semiconductor surface pits at the failure location, which corresponds to the interaction region of the gate contact edge and the edges of surface steps.

  7. Design of a GaAs/Ge solar array for unmanned aerial vehicles

    SciTech Connect (OSTI)

    Scheiman, D.A.; Colozza, A.J.; Brinker, D.J.; Bents, D.J.

    1994-12-31

    Unmanned Aerial Vehicles (UAV) are being proposed for many applications including surveillance, mapping and atmospheric studies. These applications require a lightweight, low speed, medium to long duration airplane. Due to the weight, speed, and altitude constraints imposed on such aircraft, solar array generated electric power is a viable alternative to air-breathing engines. Development of such aircraft is currently being funded under the Environmental Research Aircraft and Sensor Technology (ERAST) program. NASA Lewis Research Center (LeRC) is currently building a Solar Electric Airplane to demonstrate UAV technology. This aircraft utilizes high efficiency Applied Solar Energy Corporation (ASEC) GaAs/Ge space solar cells. The cells have been provided by the Air Force through the ManTech Office. Expected completion of the plane is early 1995, with the airplane currently undergoing flight testing using battery power.

  8. Design of a GaAs/Ge solar array for unmanned aerial vehicles

    SciTech Connect (OSTI)

    Scheiman, D.A.; Brinker, D.J.; Bents, D.J.; Colozza, A.J.

    1995-03-01

    Unmanned Aerial Vehicles (UAV) are being proposed for many applications including surveillance, mapping and atmospheric studies. These applications require a lightweight, low speed, medium to long duration airplane. Due to the weight, speed, and altitude constraints imposed on such aircraft, solar array generated electric power is a viable alternative to air-breathing engines. Development of such aircraft is currently being funded under the Environmental Research Aircraft and Sensor Technology (ERAST) program. NASA Lewis Research Center (LeRC) is currently building a Solar Electric Airplane to demonstrate UAV technology. This aircraft utilizes high efficiency Applied Solar Energy Corporation (ASEC) GaAs/Ge space solar cells. The cells have been provided by the Air Force through the ManTech Office. Expected completion of the plane is early 1995, with the airplane currently undergoing flight testing using battery power.

  9. Office of Indian Energy Policy and Programs Office of Energy...

    Office of Environmental Management (EM)

    DOE Office of Indian Energy Director-Chris Deschene 9:30-10:30 a.m. Introductions and Logistics - Sherry Stout -NREL 10:30-10:45 a.m. Summary of Tribal Leader Forum - Sarai...

  10. 1998 John Wiley & Sons, Inc. CCC 0012-1630/98/040305-08 Correspondence to: W. D. Hopkins

    E-Print Network [OSTI]

    Maestripieri, Dario

    Cline Department of Psychology Berry College Mt. Berry, GA 30149­5019 Beth Griffin Department Research Center Atlanta, GA and Department of Psychology Emory University Atlanta, GA 30322 Christopher of Psychology Agnes Scott College Decatur, GA 30030 Dario Maestripieri Yerkes Regional Primate Research Center

  11. Office of the Chief Financial Officer | Department of Energy

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

    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 Delicious Rank EERE: Alternative Fuelsof EnergyApril 2014DepartmentCouncilOffice of the Chief Financial Officer

  12. Photoeffects in WO{sub 3}/GaAs electrode

    SciTech Connect (OSTI)

    Yoon, K.H.; Lee, J.W.; Cho, Y.S.; Kang, D.H.

    1996-12-01

    Photoeffects of a {ital p}-type GaAs coated with WO{sub 3} thin film have been investigated as a function of film thickness and photoresponse transients of the WO{sub 3}/GaAs electrode were studied. Also, these results were compared to those for a single {ital p}-type GaAs electrode. The photocurrent of the WO{sub 3}/GaAs electrode depended on the film thickness of the WO{sub 3}, showing an optimum photon efficiency for specimens of 800 A thickness. This is due to the existence of an effective interface state within the band gap which reduces trapping of carriers and facilitates carrier movement. For an 800-A-thick WO{sub 3} thin film deposited {ital p}-GaAs photoelectrode, the photogenerated electrons were found to move to an electrolyte at a higher positive onset potential compared with that of single {ital p}-type GaAs, which was confirmed as a result of transient behavior. {ital I}{endash}{ital V} and {ital C}{endash}{ital V} characteristics of the WO{sub 3}/GaAs electrode were also compared with those of a single {ital p}-type GaAs electrode. {copyright} {ital 1996 American Institute of Physics.}

  13. Room temperature spin transport in undoped (110) GaAs/AlGaAs quantum wells

    SciTech Connect (OSTI)

    Yokota, Nobuhide Aoshima, Yohei; Ikeda, Kazuhiro; Kawaguchi, Hitoshi

    2014-02-17

    We are reporting on our first observation of a micrometer-order electron spin transport in a (110) GaAs/AlGaAs multiple quantum well (QW) at room temperature using a space- and time-resolved Kerr rotation technique. A 37-?m transport was observed within an electron spin lifetime of 1.2?ns at room temperature when using an in-plane electric field of 1.75?kV/cm. The spatio-temporal profiles of electron spins were well reproduced by the spin drift-diffusion equations coupled with the Poisson equation, supporting the validity of the measurement. The results suggest that (110) QWs are useful as a spin transport layer for semiconductor spintronic devices operating at room temperature.

  14. Evaluation of the two-photon absorption characteristics of GaSb/GaAs quantum rings

    SciTech Connect (OSTI)

    Wagener, M. C.; Botha, J. R.; Carrington, P. J.; Krier, A.

    2014-07-28

    The optical parameters describing the sub-bandgap response of GaSb/GaAs quantum rings solar cells have been obtained from photocurrent measurements using a modulated pseudo-monochromatic light source in combination with a second, continuous photo-filling source. By controlling the charge state of the quantum rings, the photoemission cross-sections describing the two-photon sub-bandgap transitions could be determined independently. Temperature dependent photo-response measurements also revealed that the barrier for thermal hole emission from the quantum rings is significantly below the quantum ring localisation energy. The temperature dependence of the sub-bandgap photo-response of the solar cell is also described in terms of the photo- and thermal-emission characteristics of the quantum rings.

  15. Sidewall passivation for InGaN/GaN nanopillar light emitting diodes

    SciTech Connect (OSTI)

    Choi, Won Hyuck; Abraham, Michael; Yu, Shih-Ying [Department of Materials Science and Engineering, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); You, Guanjun; Liu, Jie; Wang, Li; Xu, Jian, E-mail: jianxu@engr.psu.edu [Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Mohney, Suzanne E., E-mail: mohney@ems.psu.edu [Department of Materials Science and Engineering, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    2014-07-07

    We studied the effect of sidewall passivation on InGaN/GaN multiquantum well-based nanopillar light emitting diode (LED) performance. In this research, the effects of varying etch rate, KOH treatment, and sulfur passivation were studied for reducing nanopillar sidewall damage and improving device efficiency. Nanopillars prepared under optimal etching conditions showed higher photoluminescence intensity compared with starting planar epilayers. Furthermore, nanopillar LEDs with and without sulfur passivation were compared through electrical and optical characterization. Suppressed leakage current under reverse bias and four times higher electroluminescence (EL) intensity were observed for passivated nanopillar LEDs compared with unpassivated nanopillar LEDs. The suppressed leakage current and EL intensity enhancement reflect the reduction of non-radiative recombination at the nanopillar sidewalls. In addition, the effect of sulfur passivation was found to be very stable, and further insight into its mechanism was gained through transmission electron microscopy.

  16. Large linear magnetoresistance in a GaAs/AlGaAs heterostructure

    SciTech Connect (OSTI)

    Aamir, Mohammed Ali, E-mail: aamir@physics.iisc.ernet.in; Goswami, Srijit, E-mail: aamir@physics.iisc.ernet.in; Ghosh, Arindam [Department of Physics, Indian Institute of Science, Bangalore 560 012 (India); Baenninger, Matthias; Farrer, Ian; Ritchie, David A. [Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Tripathi, Vikram [Department of Theoretical Physics, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India); Pepper, Michael [Department of Electrical and Electronic Engineering, University College, London WC1E 7JE (United Kingdom)

    2013-12-04

    We report non-saturating linear magnetoresistance (MR) in a two-dimensional electron system (2DES) at a GaAs/AlGaAs heterointerface in the strongly insulating regime. We achieve this by driving the gate voltage below the pinch-off point of the device and operating it in the non-equilibrium regime with high source-drain bias. Remarkably, the magnitude of MR is as large as 500% per Tesla with respect to resistance at zero magnetic field, thus dwarfing most non-magnetic materials which exhibit this linearity. Its primary advantage over most other materials is that both linearity and the enormous magnitude are retained over a broad temperature range (0.3 K to 10 K), thus making it an attractive candidate for cryogenic sensor applications.

  17. Growth of GaN@InGaN Core-Shell and Au-GaN Hybrid Nanostructures for Energy Applications

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

    Kuykendall, Tevye; Aloni, Shaul; Jen-La Plante, Ilan; Mokari, Taleb

    2009-01-01

    We demonstrated a method to control the bandgap energy of GaN nanowires by forming GaN@InGaN core-shell hybrid structures using metal organic chemical vapor deposition (MOCVD). Furthermore, we show the growth of Au nanoparticles on the surface of GaN nanowires in solution at room temperature. The work shown here is a first step toward engineering properties that are crucial for the rational design and synthesis of a new class of photocatalytic materials. The hybrid structures were characterized by various techniques, including photoluminescence (PL), energy dispersive x-ray spectroscopy (EDS), transmission and scanning electron microscopy (TEM and SEM), and x-ray diffraction (XRD).

  18. LPO: Ga Power Gallery | Department of Energy

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

    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 Natural GasAdjustmentsShirley Ann JacksonDepartment ofOffice| Department ofKristina Pflanz - Writer

  19. Elastic properties of Pu metal and Pu-Ga alloys

    SciTech Connect (OSTI)

    Soderlind, P; Landa, A; Klepeis, J E; Suzuki, Y; Migliori, A

    2010-01-05

    We present elastic properties, theoretical and experimental, of Pu metal and Pu-Ga ({delta}) alloys together with ab initio equilibrium equation-of-state for these systems. For the theoretical treatment we employ density-functional theory in conjunction with spin-orbit coupling and orbital polarization for the metal and coherent-potential approximation for the alloys. Pu and Pu-Ga alloys are also investigated experimentally using resonant ultrasound spectroscopy. We show that orbital correlations become more important proceeding from {alpha} {yields} {beta} {yields} {gamma} plutonium, thus suggesting increasing f-electron correlation (localization). For the {delta}-Pu-Ga alloys we find a softening with larger Ga content, i.e., atomic volume, bulk modulus, and elastic constants, suggest a weakened chemical bonding with addition of Ga. Our measurements confirm qualitatively the theory but uncertainties remain when comparing the model with experiments.

  20. Sustainability Office University of Canterbury

    E-Print Network [OSTI]

    Hickman, Mark

    2014-2022 Sustainability Office University of Canterbury 11/6/2014 University of Canterbury Cycle ............................................................................................. 6 Encouragement of Sustainable Transport: 75th Percentile................................. 8 Encouragement of Sustainable Transport: General Campus Population..... 10 Summary

  1. Director, Office of Laboratory Policy

    Broader source: Energy.gov [DOE]

    The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, providing more than 40 percent of total funding for this vital area of...

  2. Transport properties of InGaAs/GaAs Heterostructures with {delta}-doped quantum wells

    SciTech Connect (OSTI)

    Baidus, N. V.; Vainberg, V. V.; Zvonkov, B. N.; Pylypchuk, A. S. Poroshin, V. N.; Sarbey, O. G.

    2012-05-15

    The lateral transport of electrons in single- and double-well pseudomorphic GaAs/n-InGaAs/GaAs heterostructures with quantum wells 50-100 meV deep and impurity {delta}-layers in the wells, with concentrations in the range 10{sup 11} < N{sub s} < 10{sup 12} cm{sup -2}, has been investigated. Single-well structures with a doped well at the center exhibit a nonmonotonic temperature dependence of the Hall coefficient and an increase in low-temperature electron mobility with an increase in the impurity concentration. The results obtained indicate that the impurity-band electron states play an important role in the conductivity of these structures. Involvement of the impurity band also allows to explain adequately the characteristics of the conductivity of double-well structures; in contrast to single-well structures, band bending caused by asymmetric doping is of great importance. The numerical calculations of conductivity within the model under consideration confirm these suggestions.

  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. InGaN/GaN multiple-quantum-well light-emitting diodes with a grading InN composition suppressing the Auger recombination

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    ) In conventional InGaN/GaN light-emitting diodes (LEDs), thin InGaN quantum wells are usually adopted to mitigate recombination scales with the third power of the carrier density. As a result, the efficiency droop of the Auger recombination severely limits the LED performance. Here, we proposed and showed wide InGaN quantum wells

  5. Current crowding in GaInN / GaN LEDs grown on insulating substrates X. Guo, E. F. Schubert and J. Jahns

    E-Print Network [OSTI]

    Jahns, Jürgen

    Current crowding in GaInN / GaN LEDs grown on insulating substrates X. Guo, E. F. Schubert and J. Jahns Current crowding in mesa-structure GaInN/GaN light-emitting diodes (LEDs) grown on insulating and a saturation of the optical output power at high injection currents. It is shown that the optical power

  6. Investigation of the effect of temperature during off-state degradation of AlGaN/GaN High Electron Mobility Transistors

    E-Print Network [OSTI]

    Florida, University of

    , creating both electron traps and increasing electron tunneling through the defect states [4Investigation of the effect of temperature during off-state degradation of AlGaN/GaN High Electron 2011 a b s t r a c t AlGaN/GaN High Electron Mobility Transistors were found to exhibit a negative

  7. Mesoscopic photovoltaic effect in GaAs/Ga1-xAlxAs Aharonov-Bohm rings L. Angers, A. Chepelianskii, R. Deblock, B. Reulet, and H. Bouchiat

    E-Print Network [OSTI]

    Shepelyansky, Dima

    Mesoscopic photovoltaic effect in GaAs/Ga1-xAlxAs Aharonov-Bohm rings L. Angers, A. Chepelianskii specific dc voltage. We have investigated this photovoltaic PV effect on GaAs/Ga1-xAlxAs Aharonov is generally done by measuring the dc induced signal sometimes called photovoltaic effect which has also given

  8. Determination of two-dimensional electron and hole gas carriers in AlGaN/GaN/AlN heterostructures grown by Metal

    E-Print Network [OSTI]

    Ozbay, Ekmel

    between GaN and a sapphire substrate, the dislocation scattering mechanism and the electron spillover

  9. DB-Netz AG Offices

    High Performance Buildings Database

    Hamm, Germany The new office building for DB Netz AG was designed by the collaborative team of Architrav Architects and the Buildings Physics and Technical Building Services group of the University of Karlsruhe. The team developed an energy efficient building concept for the 64,304 sqft office building, located in Hamm, Germany. The design concept of the building is dominated by architectural solutions for ventilation, cooling and lighting. Use of HVAC and electric lighting is minimized as much as possible.

  10. Atomistic description of the electronic structure of InxGa1xAs alloys and InAsGaAs superlattices

    E-Print Network [OSTI]

    Kent, Paul

    quantum-wells15,20 (InxGa1 xAs)n /InP on InP and (InxGa1 xAs)n /GaAs on GaAs, and v GaAs-embedded InAs quantum dots.21­23 We wish to provide a uniform the- oretical description of the electronic structure-period dependence of the band offsets and interband transitions of InAs/GaAs systems on InP and GaAs substrates. DOI

  11. Improved hole distribution in InGaN/GaN light-emitting diodes with graded thickness quantum barriers

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    is 48.3%. Moreover, the light output power was enhanced from 770 mW for the ETQB LEDs to 870 m; accepted 3 June 2013; published online 19 June 2013) InGaN/GaN light-emitting diodes (LEDs) with graded , which is much smaller than that of the conventional equal-thickness quantum barriers (ETQB) LED, which

  12. Low-frequency noise in GaNAlGaN heterostructure field-effect transistors at cryogenic temperatures

    E-Print Network [OSTI]

    Pala, Nezih

    that the 1/f noise in GaN/AlGaN HFETs might be caused by electron tunneling from the channel to the traps was practically independent of the frequency of analysis. The model linking this maximum to the electron tunneling Department of Electrical, Computer, and Systems Engineering and Center for Integrated Electronics

  13. Development of GaAs/Si and GaAs/Si monolithic structures for future space solar cells

    SciTech Connect (OSTI)

    Spitzer, M.B.; Vernon, S.M.; Wolfson, R.G.; Tobin, S.P.

    1984-01-01

    The results of heteroepitaxial growth of GaAs and GaAlAs directly on Si are presented, and applications to new cell structures are suggested. The novel feature is the elimination of a Ge lattice transition region. This feature not only reduces the cost of substrate preparation, but also makes possible the fabrication of high efficiency monolithic cascade structures. All films to be discussed were grown by organometallic chemical vapor deposition at atmospheric pressure. This process yielded reproducible, large-area films of GaAs, grown directly on Si, that are tightly adherent and smooth, and are characterized by a defect density of 5 x 10(6) power/sq cm. Preliminary studies indicate that GaAlAs can also be grown in this way. A number of promising applications are suggested. Certainly these substrates are ideal for low-weight GaAs space solar ells. For very high efficiency, the absence of Ge makes the technology attractive for GaAlAs/Si monolithic cascades, in which the Si substrates would first be provided with a suitable p/n junction. An evaluation of a three bandgap cascade consisting of appropriately designed GaAlAs/GaAs/Si layers is also presented.

  14. Wavelength-resolved low-frequency noise of GaInN/GaN green light emitting diodes

    E-Print Network [OSTI]

    Wetzel, Christian M.

    Wavelength-resolved low-frequency noise of GaInN/GaN green light emitting diodes S. L. Rumyantseva well light emitting diodes. The light intensity noise was measured as a function of wavelength within the light emitting diode spectral emission line. The spectral noise density is found to increase

  15. GaAs-based self-aligned laser incorporating InGaP opto-electronic confinement layer

    E-Print Network [OSTI]

    be well suited for exploitation of long wavelength quantum dot and dilute nitride technology, resulting in single lateral mode emission from an In0.17Ga0.83As double quantum well laser. Introduction: Lasers based on the GaAs materials system offer advan- tages over their InP counterparts, such as the use

  16. Improved performance of In,,Ga...As/GaAs quantum dot solar cells via light scattering by nanoparticles

    E-Print Network [OSTI]

    Yu, Edward T.

    of QDs in the context of our work is attractive for achieving long wavelength absorption in solar cells enhancement at all infrared wave- lengths in the device photocurrent spectrum. Epitaxial layer structuresImproved performance of In,,Ga...As/GaAs quantum dot solar cells via light scattering

  17. Output Harmonic Termination Techniques for AlGaN/GaN HEMT Power Amplifiers Using Active Integrated Antenna Approach

    E-Print Network [OSTI]

    Itoh, Tatsuo

    Output Harmonic Termination Techniques for AlGaN/GaN HEMT Power Amplifiers Using Active Integrated 1200, Los Angeles, CA 90045 Abstract -- In this paper, effects of output harmonic terminations on PAE termination, we observe a substantial increase in PAE and output power. Further, we demonstrate the high

  18. SnO2 functionalized AlGaN/GaN high electron mobility transistor for hydrogen sensing applications

    E-Print Network [OSTI]

    Florida, University of

    for spacecraft and other long-term sensing applications. However, hydrogen is a dangerous gas for storage for monitoring leakage of hydrogen storage equipment and fuel tanks for spacecraft and hydrogen fuel cellSnO2 functionalized AlGaN/GaN high electron mobility transistor for hydrogen sensing applications

  19. Mn-doped Ga(As,P) and (Al,Ga)As ferromagnetic semiconductors: Electronic structure calculations 

    E-Print Network [OSTI]

    Masek, J.; Kudrnovsky, J.; Maca, F.; Sinova, Jairo; MacDonald, A. H.; Campion, R. P.; Gallagher, B. L.; Jungwirth, T.

    2007-01-01

    A remarkable progress towards functional ferromagnetic semiconductor materials for spintronics has been achieved in p-type (Ga,Mn)As. Robust hole-mediated ferromagnetism has, however, been observed also in other III-V hosts such as antimonides, Ga...

  20. DESIGN, GROWTH, FABRICATION AND CHARACTERIZATION OF HIGH-BAND GAP InGaN/GaN SOLAR CELLS

    E-Print Network [OSTI]

    Honsberg, Christiana

    photovoltaic efficiency of 39% at 236 suns is achieved by a triple-junction GaInP- GaInAs-Ge tandem solar cell [1]. While the achievable efficiency of triple-junction tandem solar cells is restricted to about 40% [2], modeling results show that a tandem solar cell of five junctions or greater, or an equivalent

  1. Filter!Demonstration Microwave!Office

    E-Print Network [OSTI]

    Filter!Demonstration in Microwave!Office muse #12;Objectives · Demonstrate!project!setup!in!Microwave

  2. Office of Classroom Management 2011 Annual Report

    E-Print Network [OSTI]

    Ciocan-Fontanine, Ionut

    Office of Classroom Management 2011 Annual Report Office of Classroom Management · Academic Support Director, Office of Classroom Management Charts/graphs Table of Contents 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Office of Classroom Management 2011 Annual Report #12;1 2011 OCM Annual Report OCM's functions Scheduling

  3. UNLV OFFICE OF INFORMATION TECHNOLOGY RESPONSIBLE ADMINISTRATOR

    E-Print Network [OSTI]

    Walker, Lawrence R.

    UNLV OFFICE OF INFORMATION TECHNOLOGY RESPONSIBLE ADMINISTRATOR: RESPONSIBLE OFFICE(S): ORIGINALLY IsSUED: APPROVALS: VICE PROVOST FOR'INFORMATION TECHNOLOGY -.·..-; - OFFICE OF THE VICE PR~OST FOR INFORMATION TECHNOLOGY COMPUTER MANAGEMENT POLICY ApPROVED BY: j1/1q/;~ ~I Date REVISION DATE: NA STATEMENT

  4. OFFICE OF INFORMATION TECHNOLOGY COMPUTER SECURITY POLICY

    E-Print Network [OSTI]

    Walker, Lawrence R.

    OFFICE OF INFORMATION TECHNOLOGY COMPUTER SECURITY POLICY RESPONsmLE ADMINISTRATOR: RESPONsmLE OFFICE(S): ORIGINALLY ISSUED: ApPROVALS: VICE PROVOST FOR INFORMATION TECHNOLOGY OFFICE OF THE VICE PROVOST FOR INFORMATION TECHNOLOGY ApPROVED BY: ~ Date ~ts-tl2- Date li/rO/I?... I I Date REVISION DATE

  5. Progress toward technology transition of GaInP{sub 2}/GaAs/Ge multijunction solar cells

    SciTech Connect (OSTI)

    Keener, D.N.; Marvin, D.C.; Brinker, D.J.; Curtis, H.B.; Price, P.M.

    1997-12-31

    The objective of the joint WL/PL/NASA Multijunction Solar Cell Manufacturing Technology (ManTech) Program is to scale up high efficiency GaInP{sub 2}/GaAs/Ge multijunction solar cells to production size, quantity, and yield while limiting the production cost/Watt ($/W) to 15% over GaAs cells. Progress made by the program contractors, Spectrolab and TECSTAR, include, respectively, best cell efficiencies of 25.76% and 24.7% and establishment of 24.2% and 23.8% lot average efficiency baseline designs. The paper also presents side-by-side testing results collected by Phillips Laboratory and NASA Lewis on Phase 1 deliverable cells, which shows compliance with program objectives. Cell performance, pre- and post-radiation, and temperature coefficient results on initial production GaInP{sub 2}/GaAs/Ge solar cells will be presented.

  6. Office of Executive Resources Office of the Chief Human Capital Officer

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

    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 Delicious RankADVANCED MANUFACTURINGEnergy Bills and ReduceNovemberDOE's PrioritiesOctober 2013CommentsOfficeOffice of

  7. Ferromagnetism in undoped One-dimensional GaN Nanowires

    SciTech Connect (OSTI)

    Jeganathan, K. E-mail: jagan@physics.bdu.ac.in; Purushothaman, V.; Debnath, R.; Arumugam, S.

    2014-05-15

    We report an intrinsic ferromagnetism in vertical aligned GaN nanowires (NW) fabricated by molecular beam epitaxy without any external catalyst. The magnetization saturates at ?0.75 × emu/gm with the applied field of 3000 Oe for the NWs grown under the low-Gallium flux of 2.4 × 10{sup ?8} mbar. Despite a drop in saturation magnetization, narrow hysteresis loop remains intact regardless of Gallium flux. Magnetization in vertical standing GaN NWs is consistent with the spectral analysis of low-temperature photoluminescence pertaining to Ga-vacancies associated structural defects at the nanoscale.

  8. Characterization of Zns-GaP Naon-composites

    SciTech Connect (OSTI)

    Todd, V.

    1993-12-09

    It proved possible to produce consistent, high-quality nanocrystalline ZnS powders with grain sizes as small as 8 nm. These powders are nano-porous and are readily impregnated with GaP precursor, although inconsistently. Both crystal structure and small grain size of the ZnS can be maintained through the use of GaP. Heat treatment of the impregnated powders results in a ZnS-GaP composite structure where the grain sizes of the phases are on the order of 10--20 nm. Conventional powder processing should be able to produce optically dense ceramic compacts with improved mechanical properties and suitable IR transmission.

  9. Indium distribution at the interfaces of (Ga,In)(N,As)/GaAs quantum wells

    SciTech Connect (OSTI)

    Luna, E.; Ishikawa, F.; Batista, P. D.; Trampert, A. [Paul-Drude-Institut fuer Festkoerperelektronik, Hausvogteiplatz 5-7, D-10117, Berlin (Germany)

    2008-04-07

    The indium distribution across (Ga,In)(N,As) quantum wells is determined by using transmission electron microscopy techniques. Inside the quantum well, the indium distribution is well described by Muraki's segregation model; however, it fails in reflecting the concentration at the interfaces. To describe them, we propose a sigmoidal law which defines the smooth variation of the indium concentration with the position and provides a systematic and quantitative characterization of the interfaces. The thermal stability of the interfaces and their interplay with segregation effects are discussed. A connection between the high thermal robustness of the interfaces and the inherent thermodynamic miscibility gap of the alloy is suggested.

  10. Local Structures and Interface Morphology of InGaAsN Thin Films Grown on GaAs

    SciTech Connect (OSTI)

    Allerman, A.A.; Chen, J.G.; Geisz, J.F.; Huang, S.; Hulbert, S.L.; Jones, E.D.; Kao, Y.H.; Kurtz, S.; Kurtz, S.R.; Olson, J.M.; Soo, Y.L.

    1999-02-23

    The compound semiconductor system InGaAsN exhibits many intriguing properties which are particularly useful for the development of innovative high efficiency thin film solar cells and long wavelength lasers. The bandgap in these semiconductors can be varied by controlling the content of N and In and the thin films can yet be lattice-matched to GaAs. In the present work, x-ray absorption fine structure (XAFS) and grazing incidence x-ray scattering (GIXS) techniques have been employed to probe the local environment surrounding both N and In atoms as well as the interface morphology of InGaAsN thin films epitaxially grown on GaAs. The soft x-ray XAFS results around nitrogen K-edge reveal that N is in the sp{sup 3} hybridized bonding configuration in InGaAsN and GaAsN, suggesting that N impurities most likely substitute for As sites in these two compounds. The results of In K-edge XAFS suggest a possible trend of a slightly larger coordination number of As nearest neighbors around In atoms in InGaAsN samples with a narrower bandgap whereas the In-As interatomic distance remains practically the same as in InAs within the experimental uncertainties. These results combined suggest that N-substitution of the As sites plays an important role of bandgap-narrowing while in the meantime counteracting the compressive strain caused by In-doping. Grazing incidence x-ray scattering (GIXS) experiments verify that InGaAsN thin films can indeed form very smooth interfaces with GaAs yielding an average interfacial roughness of 5-20{angstrom}.

  11. 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.

  12. Electrical spin injection using GaCrN in a GaN based spin light emitting diode

    SciTech Connect (OSTI)

    Banerjee, D.; Ganguly, S.; Saha, D.; Adari, R.; Sankaranarayan, S.; Kumar, A.; Aldhaheri, R. W.; Hussain, M. A.; Balamesh, A. S.

    2013-12-09

    We have demonstrated electrical spin-injection from GaCrN dilute magnetic semiconductor (DMS) in a GaN-based spin light emitting diode (spin-LED). The remanent in-plane magnetization of the thin-film semiconducting ferromagnet has been used for introducing the spin polarized electrons into the non-magnetic InGaN quantum well. The output circular polarization obtained from the spin-LED closely follows the normalized in-plane magnetization curve of the DMS. A saturation circular polarization of ?2.5% is obtained at 200?K.

  13. Effects of light illumination on electron velocity of AlGaN/GaN heterostructures under high electric field

    SciTech Connect (OSTI)

    Guo, Lei; Yang, Xuelin Cheng, Jianpeng; Sang, Ling; Xu, Fujun; Tang, Ning; Feng, Zhihong; Lv, Yuanjie; Wang, Xinqiang; Shen, B.; Ge, Weikun

    2014-12-15

    We have investigated the variation of electron velocity in AlGaN/GaN heterostructures depending on illuminating light intensity and wavelength. It is shown that the electron velocity at high electric field increases under above-band light illumination. This electron velocity enhancement is found to be related to the photo-generated cold holes which interact with hot electrons and thus accelerate the energy relaxation at high electric field. The results suggest an alternative way to improve the electron energy relaxation rate and hence the electron velocity in GaN based heterostructures.

  14. High-power InGaAs/GaAs quantum-well laser with enhanced broad spectrum of stimulated emission

    SciTech Connect (OSTI)

    Wang, Huolei; Yu, Hongyan; Zhou, Xuliang; Kan, Qiang; Yuan, Lijun; Wang, Wei; Pan, Jiaoqing, E-mail: jqpan@semi.ac.cn [Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Science, Beijing 100083 (China); Chen, Weixi [State Key Lab for Mesoscopic Physics and School of Physics, Peking University, Beijing 100871 (China); Ding, Ying, E-mail: Ying.Ding@glasgow.ac.uk [School of Engineering, University of Glasgow, Glasgow G12 8LT (United Kingdom)

    2014-10-06

    We report the demonstration of an InGaAs/GaAs quantum well (QW) broadband stimulated emission laser with a structure that integrated a GaAs tunnel junction with two QW active regions. The laser exhibits ultrabroad lasing spectral coverage of ?51?nm at a center wavelength of 1060?nm with a total emission power of 790 mW, corresponding to a high average spectral power density of 15.5 mW/nm, under pulsed current conditions. Compared to traditional lasers, this laser with an asymmetric separate-confinement heterostructure shows broader lasing bandwidth and higher spectral power density.

  15. Linear and nonlinear optical properties of GaAs/Al{sub x}Ga{sub 1?x}As/GaAs/Al{sub y}Ga{sub 1?y}As multi-shell spherical quantum dot

    SciTech Connect (OSTI)

    Emre Kavruk, Ahmet E-mail: aekavruk@gmail.com; Koc, Fatih; Sahin, Mehmet E-mail: mehsahin@gmail.com

    2013-11-14

    In this work, the optical properties of GaAs/Al{sub x}Ga{sub 1?x}As/GaAs/Al{sub y}Ga{sub 1?y}As multi-shell quantum dot heterostructure have been studied as a function of Al doping concentrations for cases with and without a hydrogenic donor atom. It has been observed that the absorption coefficient strength and/or resonant absorption wavelength can be adjusted by changing the Al content of inner-barrier and/or outer-barrier regions. Besides, it has been shown that the donor atom has an important effect on the control of the electronic and optical properties of the structure. The results have been presented as a function of the Al contents of the inner-barrier x and outer-barrier y regions and probable physical reasons have been discussed.

  16. Electrical degradation mechanisms of RF power GaAs PHEMTs

    E-Print Network [OSTI]

    Villanueva, Anita A. (Anita Ariel), 1978-

    2007-01-01

    GaAs Pseudomorphic High-Electron Mobility Transistors (PHEMTs) are widely used in RF power applications. Since these devices typically operate at high power levels and under high voltage biasing, their electrical reliability ...

  17. 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.

  18. Fermilab | Directorate | Program Planning Office

    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) | SciTech ConnectTimothyOffices Office ofProgram

  19. Low temperature carrier redistribution dynamics in InGaN/GaN quantum wells

    SciTech Connect (OSTI)

    Badcock, T. J., E-mail: Thomas.badcock@crl.toshiba.co.uk; Dawson, P.; Davies, M. J. [School of Physics and Astronomy, Photon Science Institute, Alan Turing Building, University of Manchester, Manchester M13 9PL (United Kingdom); Kappers, M. J.; Massabuau, F. C.-P.; Oehler, F.; Oliver, R. A.; Humphreys, C. J. [Department of Materials Science and Metallurgy, 27 Charles Babbage Road, University of Cambridge, Cambridge CB3 0FS (United Kingdom)

    2014-03-21

    We have studied the carrier recombination dynamics in an InGaN/GaN multiple quantum well structure as a function of emission energy and excitation density between temperatures of 10?K and 100?K. Under relatively low levels of excitation, the photoluminescence (PL) intensity and decay time of emission on the high energy side of the luminescence spectrum decrease strongly between 10?K and 50?K. In contrast, for emission detected on the low energy side of the spectrum, the PL intensity and decay time increase over the same temperature range. These results are consistent with a thermally activated carrier redistribution process in which the (temperature dependent) average timescale for carrier transfer into or out of a localised state depends on the energy of the given state. Thus, the transfer time out of shallow, weakly localised states is considerably shorter than the arrival time into more deeply localised states. This picture is consistent with carriers hopping between localisation sites in an uncorrelated disorder potential where the density of localised states decreases with increasing localisation depth, e.g., a exponential or Gaussian distribution resulting from random alloy disorder. Under significantly higher levels of excitation, the increased occupation fraction of the localised states results in a greater average separation distance between unoccupied localised states, causing a suppression of the spectral and dynamic signatures of the hopping transfer of carriers.

  20. Green (In,Ga,Al)P-GaP light-emitting diodes grown on high-index GaAs surfaces

    SciTech Connect (OSTI)

    Ledentsov, N. N., E-mail: nikolay.ledentsov@v-i-systems.com; Shchukin, V. A. [VI Systems GmbH, Hardenbergstr. 7, Berlin D-10623 (Germany); Lyytikäinen, J.; Okhotnikov, O. [Optoelectronics Research Centre, Tampere University of Technology, Tampere FI-33720 (Finland); Shernyakov, Yu. M.; Payusov, A. S.; Gordeev, N. Yu.; Maximov, M. V. [A. F. Ioffe Physical Technical Institute of the Russian Academy of Sciences, Politekhnicheskaya 26, St. Petersburg 194021 (Russian Federation); Schlichting, S.; Nippert, F.; Hoffmann, A. [Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstrasse 36, Berlin D-10623 (Germany)

    2014-11-03

    We report on green (550–560?nm) electroluminescence (EL) from (Al{sub 0.5}Ga{sub 0.5}){sub 0.5}In{sub 0.5}P-(Al{sub 0.8}Ga{sub 0.2}){sub 0.5}In{sub 0.5}P double p-i-n heterostructures with monolayer-scale GaP insertions in the cladding layers and light-emitting diodes based thereupon. The structures are grown side-by-side on high-index and (100) GaAs substrates by molecular beam epitaxy. At moderate current densities (?500?A/cm{sup 2}), the EL intensity of the structures is comparable for all substrate orientations. Opposite to the (100)-grown strictures, the EL spectra of (211) and (311)-grown devices are shifted towards shorter wavelengths (?550?nm at room temperature). At high current densities (>1?kA/cm{sup 2}), a much higher EL intensity is achieved for the devices grown on high-index substrates. The integrated intensity of (311)-grown structures gradually saturates at current densities above 4?kA/cm{sup 2}, whereas no saturation is revealed for (211)-grown structures up to the current densities above 14?kA/cm{sup 2}. We attribute the effect to the surface orientation-dependent engineering of the GaP band structure, which prevents the escape of the nonequilibrium electrons into the indirect conduction band minima of the p-doped (Al{sub 0.8}Ga{sub 0.2}){sub 0.5}In{sub 0.5}P cladding layers.

  1. Office Ergonomics: Setting Up Your Workstation Office of Environmental Health & Safety: www.ehs.utoronto.ca, ehs.office@utoronto.ca, 416.978.4467

    E-Print Network [OSTI]

    Chan, Hue Sun

    Office Ergonomics: Setting Up Your Workstation Office of Environmental Health & Safety: www. Turn the page #12;Office Ergonomics: Setting Up Your Workstation Office of Environmental Health Ddddddddddddddddd Office Ergonomics: Dos & Don'ts Do take the Online Office Ergonomics course which provides more

  2. Influence of stress on optical transitions in GaN nanorods containing a single InGaN/GaN quantum disk

    SciTech Connect (OSTI)

    Zhuang, Y. D.; Shields, P. A.; Allsopp, D. W. E., E-mail: d.allsopp@bath.ac.uk [Department of Electronic and Electrical Engineering, University of Bath, Bath BA2 7AY (United Kingdom); Bruckbauer, J.; Edwards, P. R.; Martin, R. W. [Department of Physics, SUPA, University of Strathclyde, Glasgow G4 0NG (United Kingdom)

    2014-11-07

    Cathodoluminescence (CL) hyperspectral imaging has been performed on GaN nanorods containing a single InGaN quantum disk (SQD) with controlled variations in excitation conditions. Two different nanorod diameters (200 and 280?nm) have been considered. Systematic changes in the CL spectra from the SQD were observed as the accelerating voltage of the electron beam and its position of incidence are varied. It is shown that the dominant optical transition in the SQD varies across the nanorod as a result of interplay between the contributions of the deformation potential and the quantum-confined Stark effect to the transition energy as consequence of radial variation in the pseudomorphic strain.

  3. Partnering Policy for the Office of Environmental Management...

    Office of Environmental Management (EM)

    Policy for the Office of Environmental Management Partnering Policy for the Office of Environmental Management Partnering Policy for the Office of Environmental Management More...

  4. Fuel Cell Technologies Office Newsletter: May 2015 | Department...

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

    Fuel Cell Technologies Office Newsletter: May 2015 Fuel Cell Technologies Office Newsletter: May 2015 The May 2015 issue of the Fuel Cell Technologies Office (FCTO) newsletter...

  5. NA GC - Office of General Counsel | National Nuclear Security...

    National Nuclear Security Administration (NNSA)

    Blog Home About Us Our Operations Management and Budget Office of Civil Rights Workforce Statistics NA GC - Office of General Counsel NA GC - Office of General Counsel...

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    National Nuclear Security Administration (NNSA)

    Us Our Operations Management and Budget Office of Civil Rights Workforce Statistics Savannah River Field Office Savannah River Field Office FY15 Semi Annual Report...

  7. NA 1 - Immediate Office of the Administrator | National Nuclear...

    National Nuclear Security Administration (NNSA)

    Us Our Operations Management and Budget Office of Civil Rights Workforce Statistics NA 1 - Immediate Office of the Administrator NA 1 - Immediate Office of the...

  8. Kansas City Field Office | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    Us Our Operations Management and Budget Office of Civil Rights Workforce Statistics Kansas City Field Office Kansas City Field Office FY15 Semi Annual Report FY14...

  9. Los Alamos Field Office | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    Us Our Operations Management and Budget Office of Civil Rights Workforce Statistics Los Alamos Field Office Los Alamos Field Office FY15 Semi Annual Report FY14 Year...

  10. 2013 Annual Planning Summary for the Office of River Protection...

    Energy Savers [EERE]

    River Protection and Richland Operations Office 2013 Annual Planning Summary for the Office of River Protection and Richland Operations Office The ongoing and projected...

  11. 2015 Building Technologies Office Program Peer Review Report...

    Office of Environmental Management (EM)

    Building Technologies Office Program Peer Review Report 2015 Building Technologies Office Program Peer Review Report The 2015 Building Technologies Office Program Peer Review...

  12. 2014 Building Technologies Office Program Peer Review Report...

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

    4 Building Technologies Office Program Peer Review Report 2014 Building Technologies Office Program Peer Review Report The 2014 Building Technologies Office Program Peer Review...

  13. Office of Energy Efficiency and Renewable Energy's Integrated...

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

    Office of Energy Efficiency and Renewable Energy's Integrated Resource and Information System DOEIG-0905 April 2014 U.S. Department of Energy Office of Inspector General Office of...

  14. California Employment Growth and Office, Industrial, and Retail Markets, 1990

    E-Print Network [OSTI]

    Kroll, Cynthia; Tamura, Dina

    1990-01-01

    Office, Industrial, and Retail Markets, 1990 HE Californiastate's major office and retail markets. Services employmentstate's major office and retail markets." Like manufacturing

  15. US Department of Energy Office of Energy Efficiency and Renewable...

    Open Energy Info (EERE)

    US Department of Energy Office of Energy Efficiency and Renewable Energy (DOE EERE) Jump to: navigation, search Logo: Office of Energy Efficiency and Renewable Energy Name: Office...

  16. TO: Procurement Directors/Contracting Officers FROM: Director

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

    0 DATE: May 30, 2014 TO: Procurement DirectorsContracting Officers FROM: Director Contract and Financial Assistance Policy Division Office of Policy Office of Procurement and...

  17. TO: Procurement Directors/Contracting Officers FROM: Director

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

    4 DATE: July 7, 2014 TO: Procurement DirectorsContracting Officers FROM: Director Contract and Financial Assistance Policy Division Office of Policy Office of Procurement and...

  18. Department of Energy Office of Science Transportation Overview...

    Office of Environmental Management (EM)

    Energy Office of Science Transportation Overview Department of Energy Office of Science Transportation Overview Overview of the Office of Science for Transportation. Department of...

  19. DOE Fuel Cell Technologies Office: 2013 Fuel Cell Seminar and...

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

    Office: 2013 Fuel Cell Seminar and Energy Exposition DOE Fuel Cell Technologies Office: 2013 Fuel Cell Seminar and Energy Exposition Overview of DOE's Fuel Cell Technologies Office...

  20. About the Sustainability Performance Office | Department of Energy

    Energy Savers [EERE]

    the Sustainability Performance Office About the Sustainability Performance Office The U.S. Department of Energy (DOE) Sustainability Performance Office (SPO) oversees departmental...

  1. Chicago Office NEPA Tracking Number U. S. DEPARTMENT OF ENERGY

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

    CH F 560-ACQ (1105) Previous editions are obsolete. Chicago Office NEPA Tracking Number U. S. DEPARTMENT OF ENERGY OFFICE OF SCIENCE -- CHICAGO OFFICE NATIONAL ENVIRONMENTAL...

  2. Independent Oversight Review of the NNSA Production Office Readiness...

    Energy Savers [EERE]

    Independent Oversight Review of the NNSA Production Office Readiness Review Program February 2014 Office of Safety and Emergency Management Evaluations Office of Enforcement and...

  3. Occupational Health Manager PIA, Carlsbad Field Office | Department...

    Energy Savers [EERE]

    Occupational Health Manager PIA, Carlsbad Field Office Occupational Health Manager PIA, Carlsbad Field Office Occupational Health Manager PIA, Carlsbad Field Office PDF icon...

  4. High intensity low temperature (HILT) performance of space concentrator GaInP/GaInAs/Ge MJ SCs

    SciTech Connect (OSTI)

    Shvarts, Maxim Z., E-mail: shvarts@scell.ioffe.ru; Kalyuzhnyy, Nikolay A.; Mintairov, Sergey A.; Soluyanov, Andrei A.; Timoshina, Nailya Kh. [Ioffe Physical-Technical Institute, 26 Polytekhnicheskaya str., St.-Petersburg, 194021 (Russian Federation); Gudovskikh, Alexander S. [Saint-Petersburg Academic University - Nanotechnology Research and Education Centre RAS, St. Petersburg, 194021 (Russian Federation); Luque, Antonio [Ioffe Physical-Technical Institute, 26 Polytekhnicheskaya str., St.-Petersburg, 194021, Russia and Instituto de Energia Solar, Universidad Politecnica de Madrid, Madrid (Spain)

    2014-09-26

    In the work, the results of an investigation of GaInP/GaInAs/Ge MJ SCs intended for converting concentrated solar radiation, when operating at low temperatures (down to ?190 °C) are presented. A kink of the cell I-V characteristic has been observed in the region close to V{sub oc} starting from ?20°C at operation under concentrated sunlight. The causes for its occurrence have been analyzed and the reasons for formation of a built-in potential barrier for majority charge carriers at the n-GaInP/n-Ge isotype hetero-interface are discussed. The effect of charge carrier transport in n-GaInP/n-pGe heterostructures on MJ SC output characteristics at low temperatures has been studied including EL technique.

  5. The origin and reduction of switching noise in GaAs/AlGaAs lateral gated devices

    E-Print Network [OSTI]

    Davies, John H.

    to cryogenic temperature with all gates grounded to the substrate to protect against electrostatic effects in AlGaAs: electrons `freeze' into deep traps ­ DX centres ­ below about 150 K. The occupation of donors

  6. Design and fabrication of InGaN/GaN heterojunction bipolar transistors for microwave power amplifiers

    E-Print Network [OSTI]

    Keogh, David Martin

    2006-01-01

    assuming the material growth technology allows for all ofand a relatively immature growth technology, as well as theof the art for InGaN growth technology. Epitaxial growth of

  7. Polarization field engineering of GaN/AlN/AlGaN superlattices for enhanced thermoelectric properties

    SciTech Connect (OSTI)

    Sztein, Alexander, E-mail: asztein@umail.ucsb.edu [Materials Department, University of California, Santa Barbara, California 93106 (United States); Bowers, John E.; DenBaars, Steven P.; Nakamura, Shuji [Materials Department, University of California, Santa Barbara, California 93106 (United States); Electrical and Computer Engineering Department, University of California, Santa Barbara, California 93106 (United States)

    2014-01-27

    A novel polarization field engineering based strategy to simultaneously achieve high electrical conductivity and low thermal conductivity in thermoelectric materials is demonstrated. Polarization based electric fields are used to confine electrons into two-dimensional electron gases in GaN/AlN/Al{sub 0.2}Ga{sub 0.8}N superlattices, resulting in improved electron mobilities as high as 1176 cm{sup 2}/Vs and in-plane thermal conductivity as low as 8.9?W/mK. The resulting room temperature ZT values reach 0.08, a factor of four higher than InGaN and twelve higher than GaN, demonstrating the potential benefits of this polarization based engineering strategy for improving the ZT and efficiencies of thermoelectric materials.

  8. Si-CMOS-Like Integration of AlGaN/GaN Dielectric-Gated High-Electron-Mobility Transistors 

    E-Print Network [OSTI]

    Johnson, Derek Wade

    2014-07-31

    production is projected to consume ~100,000 wafers per year by 2015 (Yole Development, “Power GaN – 2012 Edition”), this manufacturing breakthrough represents potential savings of ~$17 million per year....

  9. Characterization of the gate oxide of an AlGaN/GaN high electron mobility transistor

    E-Print Network [OSTI]

    Florida, University of

    2011; published online 21 March 2011 A subnanometer thick interfacial oxide layer present between used to characterize a Ni/AlGaN interfacial oxide layer with subnanometer thickness. The semiconducting

  10. The first principle study of Ni{sub 2}ScGa and Ni{sub 2}TiGa

    SciTech Connect (OSTI)

    Özduran, Mustafa; Turgut, Kemal; Arikan, Nihat; ?yigör, Ahmet; Candan, Abdullah

    2014-10-06

    We computed the electronic structure, elastic moduli, vibrational properties, and Ni{sub 2}TiGa and Ni{sub 2}ScGa alloys in the cubic L2{sub 1} structure. The obtained equilibrium lattice constants of these alloys are in good agreement with available data. In cubic systems, there are three independent elastic constants, namely C{sub 11}, C{sub 12} and C{sub 44}. We calculated elastic constants in L2{sub 1} structure for Ni{sub 2}TiGa and Ni{sub 2}ScGa using the energy-strain method. The electronic band structure, total and partial density of states for these alloys were investigated within density functional theory using the plane-wave pseudopotential method implemented in Quantum-Espresso program package. From band structure, total and projected density of states, we observed metallic characters of these compounds. The electronic calculation indicate that the predominant contributions of the density of states at Fermi level come from the Ni 3d states and Sc 3d states for Ni{sub 2}TiGa, Ni 3d states and Sc 3d states for Ni{sub 2}ScGa. The computed density of states at Fermi energy are 2.22 states/eV Cell for Ni{sub 2}TiGa, 0.76 states/eV Cell for Ni{sub 2}ScGa. The vibrational properties were obtained using a linear response in the framework at the density functional perturbation theory. For the alloys, the results show that the L2{sub 1} phase is unstable since the phonon calculations have imagine modes.

  11. Information Security Office Risk Management

    E-Print Network [OSTI]

    Alpay, S. Pamir

    Information Security Office Risk Management Exception Template #12;Risk Management Exception or Approved) 6/01/2013 CISO Jason Pufahl, CISO Approved 6/01/2013 RMAC Risk Management Advisory Council Reviewed #12;Risk Management Exception Template 2 | P a g e Please check one of the following: Requester

  12. Office: ITO PE/Project

    E-Print Network [OSTI]

    Mills, Kevin

    Mgr.: Mills/Swinson PAD No.: Smart Spaces Moving Through Smart Spaces "city-wide appliances" "in1 DARPA Office: ITO PE/Project: Pgm No.: Pgm Mgr.: Mills/Swinson PAD No.: Smart Spaces Personal Information Projection · Develop techniques for projecting personal information from cyberspace into smart

  13. OFFICE OF SUPPLIER DIVERSITY DEVELOPMENT

    E-Print Network [OSTI]

    Pittendrigh, Barry

    OFFICE OF SUPPLIER DIVERSITY DEVELOPMENT STRATEGIC PLAN JESSE MOORE, MANAGER August, 2005 Mission Statement Provide leadership and develop relationships that will result in Purdue's campus' supplier base is a recognized national leader in developing a diverse supplier base. All staff involved with purchasing

  14. Optical investigation of InAs quantum dots inserted in AlGaAs/GaAs modulation doped heterostructure

    SciTech Connect (OSTI)

    Khmissi, H.; Baira, M.; Bouzaieene, L.; Saidi, F.; Maaref, H. [Laboratoire de Micro-optoelectronique et Nanostructures, Universite de Monastir (Tunisia); Sfaxi, L. [Laboratoire de Micro-optoelectronique et Nanostructures, Universite de Monastir (Tunisia); Universite de Sousse Faculte des Sciences de Monastir, Avenue de l'Environnement 5019 Monastir (Tunisia); Bru-Chevallier, C. [Institut des Nanotechnologies de Lyon (INL), CNRS UMR-5270, INSA-LYON, 7, Avenue Jean Capelle, Bat. Blaise Pascal, 69621 Villeurbanne (France)

    2011-03-01

    Optical properties of InAs quantum dots (QDs) inserted in AlGaAs/GaAs modulation doped heterostructure are investigated. To study the effect of carrier transfer behavior on the luminescence of self-assembled quantum dots, a series of sample has been prepared using molecular beam epitaxy (Riber 32 system) in which we have varied the thickness separating the delta dopage and the InAs quantum dots layer. Photoluminescence spectra show the existence of two peaks that can be attributed to transition energies from the ground state (E{sub 1}-HH{sub 1}) and the first excited state (E{sub 2}-HH{sub 2}). Two antagonist effects have been observed, a blue shift of the emission energies result from electron transferred from the AlGaAs/GaAs heterojunction to the InAs quantum dots and a red shift caused by the quantum confined Stark effect due to the internal electric field existing In the AlGaAs/GaAs heterojunction.

  15. Effects of high-temperature AIN buffer on the microstructure of AlGaN/GaN HEMTs

    SciTech Connect (OSTI)

    Coerekci, S.; Oeztuerk, M. K.; Yu, Hongbo; Cakmak, M.; Oezcelik, S.; Oezbay, E.

    2013-06-15

    Effects on AlGaN/GaN high-electron-mobility transistor structure of a high-temperature AlN buffer on sapphire substrate have been studied by high-resolution x-ray diffraction and atomic force microscopy techniques. The buffer improves the microstructural quality of GaN epilayer and reduces approximately one order of magnitude the edge-type threading dislocation density. As expected, the buffer also leads an atomically flat surface with a low root-mean-square of 0.25 nm and a step termination density in the range of 10{sup 8} cm{sup -2}. Due to the high-temperature buffer layer, no change on the strain character of the GaN and AlGaN epitaxial layers has been observed. Both epilayers exhibit compressive strain in parallel to the growth direction and tensile strain in perpendicular to the growth direction. However, an high-temperature AlN buffer layer on sapphire substrate in the HEMT structure reduces the tensile stress in the AlGaN layer.

  16. Director, Salt Waste Processing Facility Project Office

    Broader source: Energy.gov [DOE]

    This position is located within The Department of Energy (DOE) Savannah River (SR) Operations Office, Salt Waste Processing Facility Project Office (SWPFPO). SR is located in Aiken, South Carolina....

  17. DOE Office of Indian Energy Overview Brochure

    Office of Energy Efficiency and Renewable Energy (EERE)

    The U.S. Department of Energy (DOE) Office of Indian Energy Stengthening Tribal Communities, Sustaining Future Generations is an overview brochure with information on the Office of Indian Energy's education and capacity building, technical assistance, and resources for tribes.

  18. New Mexico State University Controller's Office

    E-Print Network [OSTI]

    Johnson, Eric E.

    New Mexico State University Controller's Office MOU Remote Document Submission - Version B CO by the Remote Office or are of no value are destroyed according to New Mexico Administrative Codes (NMAC

  19. 4-H Club Officer Handbook - Parliamentarian 

    E-Print Network [OSTI]

    Howard, Jeff W.

    2006-08-09

    This section from the 4-H Club Officer Handbook features the multi-faceted role of the Parliamentarian. It covers the officer's duties, including how to keep order at club meetings through making and amending motions. ...

  20. 4-H Club Officer Handbook - Secretary 

    E-Print Network [OSTI]

    Howard, Jeff W.

    2006-08-09

    This section from the 4-H Club Officer Handbook features the multi-faceted role of the Secretary. It covers the officer's duties, including how to get organized for the start of your 4-H Club year. Other highlights include ...

  1. Finance and Enterprises Office February 2014

    E-Print Network [OSTI]

    Tam, Vincent W. L.

    Finance and Enterprises Office February 2014 Office Management Student matters Insurance HKU SPACE Planning & Management Associate Director of Finance ----------------------------------- Antony Hui Associate Director of Finance ----------------------------------- Edmund Li Assistant Director of Finance

  2. Division, NN-43, Office of Arms Control

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

    as a Presiding Officer, and will not be re- sponsible to or subject to the super- vision or direction of any officer or em- ployee engaged in the performance of an...

  3. The University of Vermont Office of Admissions

    E-Print Network [OSTI]

    Bermingham, Laura Hill

    1 The University of Vermont Office of Admissions DISCOVERING UVM: Strong Voices, Open Minds are optional modes of transportation to Burlington, Vermont: Airlines Continental Airlines www Bushey University of Vermont, Office of Admissions 194 South Prospect St., Burlington, Vermont 05401

  4. Energy use in office buildings

    SciTech Connect (OSTI)

    None

    1980-10-01

    This is the report on Task IB, Familiarization with Additional Data Collection Plans of Annual Survey of BOMA Member and Non-Member Buildings in 20 Cities, of the Energy Use in Office Buildings project. The purpose of the work was to monitor and understand the efforts of the Building Owners and Managers Association International (BOMA) in gathering an energy-use-oriented data base. In order to obtain an improved data base encompassing a broad spectrum of office space and with information suitable for energy analysis in greater detail than is currently available, BOMA undertook a major data-collection effort. Based on a consideration of geographic area, climate, population, and availability of data, BOMA selected twenty cities for data collection. BOMA listed all of the major office space - buildings in excess of 40,000 square feet - in each of the cities. Tax-assessment records, local maps, Chamber of Commerce data, recent industrial-development programs, results of related studies, and local-realtor input were used in an effort to assemble a comprehensive office-building inventory. In order to verify the accuracy and completeness of the building lists, BOMA assembled an Ad-Hoc Review Committee in each city to review the assembled inventory of space. A questionnaire on office-building energy use and building characteristics was developed. In each city BOMA assembled a data collection team operating under the supervision of its regional affiliate to gather the data. For each city a random sample of buildings was selected, and data were gathered. Responses for over 1000 buildings were obtained.

  5. Mathematics Business Office - Department of Mathematics, Purdue ...

    E-Print Network [OSTI]

    $author.value

    Mathematics Business Office. Welcome to new faculty · Moving Procedures · Forms · Travel; Research. Pre-Award Center · Vice President for Research ...

  6. Advanced Manufacturing Office Overview | Department of Energy

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

    Office Overview mwrfworkshopjuly2012.pdf More Documents & Publications Microwave and Radio Frequency Workshop Manufacturing Demonstration Facility Workshop...

  7. Hudson Valley Clean Energy Office and Warehouse

    High Performance Buildings Database

    Rhinebeck, NY Hudson Valley Clean Energy's new head office and warehouse building in Rhinebeck, New York, achieved proven net-zero energy status on July 2, 2008, upon completing its first full year of operation. The building consists of a lobby, meeting room, two offices, cubicles for eight office workers, an attic space for five additional office workers, ground- and mezzanine-level parts and material storage, and indoor parking for three contractor trucks.

  8. Office of Classification | Department of Energy

    Office of Environmental Management (EM)

    Classification Officers, HQ Classification Representatives, Secret Original Classifiers, Top Secret Derivative Classifiers, HQ Derivative Classifiers and HQ UCNI Reviewing...

  9. Vehicle Technologies Office: Maximizing Alternative Fuel Vehicle...

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

    Maximizing Alternative Fuel Vehicle Efficiency Vehicle Technologies Office: Maximizing Alternative Fuel Vehicle Efficiency Besides their energy security and environmental benefits,...

  10. Office of Environmental Protection, Sustainability Support &...

    Energy Savers [EERE]

    Environmental Protection, Sustainability Support & Corporate Safety Analysis Office of Environmental Protection, Sustainability Support & Corporate Safety Analysis Mission The...

  11. Office of Research Opportunity | The Ames Laboratory

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

    Research Opportunity The Office of Research Opportunities (ORO) is responsible for identifying and disseminating Funding Opportunity Announcements, coordinating complex or...

  12. p-doping-free InGaN/GaN light-emitting diode driven by three-dimensional hole gas

    SciTech Connect (OSTI)

    Zhang, Zi-Hui; Tiam Tan, Swee; Kyaw, Zabu; Liu, Wei; Ji, Yun; Ju, Zhengang; Zhang, Xueliang [LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore (Singapore) [LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore (Singapore); LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Physical and Mathematical Sciences, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore (Singapore); Wei Sun, Xiao, E-mail: EXWSUN@ntu.edu.sg [LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore (Singapore); LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Physical and Mathematical Sciences, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore (Singapore); Department of Electronics and Electrical Engineering, South University of Science and Technology of China, Shenzhen, Guangdong 518055 (China); Volkan Demir, Hilmi, E-mail: VOLKAN@stanfordalumni.org [LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore (Singapore); LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Physical and Mathematical Sciences, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore (Singapore); Department of Electrical and Electronics, UNAM-Institute of Material Science and Nanotechnology, Bilkent University, Ankara TR-06800 (Turkey); Department of Physics, UNAM-Institute of Material Science and Nanotechnology, Bilkent University, Ankara TR-06800 (Turkey)

    2013-12-23

    Here, GaN/Al{sub x}Ga{sub 1-x}N heterostructures with a graded AlN composition, completely lacking external p-doping, are designed and grown using metal-organic-chemical-vapour deposition (MOCVD) system to realize three-dimensional hole gas (3DHG). The existence of the 3DHG is confirmed by capacitance-voltage measurements. Based on this design, a p-doping-free InGaN/GaN light-emitting diode (LED) driven by the 3DHG is proposed and grown using MOCVD. The electroluminescence, which is attributed to the radiative recombination of injected electrons and holes in InGaN/GaN quantum wells, is observed from the fabricated p-doping-free devices. These results suggest that the 3DHG can be an alternative hole source for InGaN/GaN LEDs besides common Mg dopants.

  13. Lasing characteristics of GaSb/GaAs self-assembled quantum dots embedded in an InGaAs quantum well

    E-Print Network [OSTI]

    Jalali. Bahram

    Center for High Technology Materials, University of New Mexico, 1313 Goddard SE, Albuquerque, New Mexico, New Mexico 87545 Received 26 February 2007; accepted 1 June 2007; published online 28 June 2007 intriguing optoelectronic device possibilities on GaAs substrates including lasers, detectors, or solar cells

  14. University of Minnesota Office of Classroom Management

    E-Print Network [OSTI]

    Thomas, David D.

    University of Minnesota Office of Classroom Management "Low End" Asynchronous Videostreaming Pilot Office of Classroom Management "Low End" Asynchronous Videostreaming Pilot Project Evaluation Contents and testing of "low end" asynchronous video streaming as a Phase III in The Office of Classroom Management

  15. Office of the President University Policy

    E-Print Network [OSTI]

    Fernandez, Eduardo

    supervisor, the Office of the Inspector General or the Office of the General Counsel. Suspected fraud, waste complaint form on the Office of Inspector General's website - http://www.fau.edu/admin/oig/complaint.php. IV these activities and/or make them easier to detect and prevent; and provide for the reporting and investigation

  16. Table of Contents 3 Officers and Administration

    E-Print Network [OSTI]

    He, Chuan

    #12;Table of Contents 3 Officers and Administration 7 The Field and the School 15 Educational Agencies 176 SSA Calendar 178 Index #12;School of Social Service Administration 3 Officers and Administration Officers of the University Andrew M. Alper, Chairman of the Board of Trustees Robert J. Zimmer

  17. Office of Marine and Aviation Operations NOAA's Office of Marine and Aviation Operations

    E-Print Network [OSTI]

    Office of Marine and Aviation Operations NOAA's Office of Marine and Aviation Operations (OMAO) 101 2015 #12;Office of Marine and Aviation Operations For future questions and information on OMAO://www.legislative.noaa.gov/. #12;Office of Marine and Aviation Operations Director, OMAO and the NOAA Corps Rear Admiral David A

  18. Standards Panel: 1. Stephen Diamond, General Manager, Industry Standards Office and Global Standards Officer, EMC

    E-Print Network [OSTI]

    Standards Panel: 1. Stephen Diamond, General Manager, Industry Standards Office and Global was President of the IEEE Computer Society. Steve is General Manager of the Industry Standards Office at EMC Standards Officer, EMC Corporation, Office of the CTO Steve Diamond has 30 years of management, marketing

  19. Industrial Feedstock Flexibility Workshop Results

    SciTech Connect (OSTI)

    Ozokwelu, Dickson; Margolis, Nancy; Justiniano, Mauricio; Monfort, Joe; Brueske, Sabine; Sabouni, Ridah

    2009-08-01

    This report (PDF 649 KB) summarizes the results of the 2009 Industrial Feedstock Flexibility Workshop, which took place in Atlanta, GA on August 19-20, 2009.

  20. Th

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

    I 2 S-LWR Integral Inherently Safe Light Water Reactor Bojan Petrovic Nuclear and Radiological Engineering Georgia Institute of Technology, Atlanta, GA, USA DOE-NE Materials...

  1. RESIDENTIAL THERMOSTATS: COMFORT CONTROLS IN CALIFORNIA HOMES

    E-Print Network [OSTI]

    Meier, Alan K.

    2008-01-01

    for Residential Winter and Summer Air Conditioning.Air Conditioning Contractors of America. Washington, DC.refrigerating and Air-conditioning Engineers, Atlanta, GA.

  2. Securing Wireless Data Networks against Eavesdropping Using Smart Antennas Sriram Lakshmanan, Cheng-Lin Tsao, Raghupathy Sivakumar

    E-Print Network [OSTI]

    Sivakumar, Raghupathy

    Securing Wireless Data Networks against Eavesdropping Using Smart Antennas Sriram Lakshmanan, Cheng-Lin Tsao, Raghupathy Sivakumar Georgia Institute of Technology Atlanta,GA,USA {sriram

  3. Context-Sensitive Resource Discovery Guanling Chen and David Kotz

    E-Print Network [OSTI]

    Kotz, David

    and/or a fee. SIGCSE'98. Atlanta, GA, USA. Copyright 1998 ACM 0-89791-994-7/98/2...$5.00. If we want

  4. Are We Closing the School Discipline Gap?

    E-Print Network [OSTI]

    Losen, Daniel; Hodson, Cheri; Keith II, Michael A; Morrison, Katrina; Belway, Shakti

    2015-01-01

    the following: Atlanta, GA; Baltimore City, MD; Boston, MA;CT), Oklahoma City (OK), Baltimore City (MD), Montgomery (administrators in Baltimore, Los Angeles, and elsewhere (

  5. Better Buildings Residential Financing and Revenue Peer Exchange...

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

    started? Future Call Topics 2 Call Participants Atlanta, GA Augusta, ME Baltimore, MD Chicago, IL Connecticut Kansas City, MO Saint Lucie County, FL ...

  6. NETL F 451.1/1-1, Categorical Exclusion Designation Form

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

    163 Praxair, Inc. Tonawanda, WV Georgia Institute of Technology, 505 10th Street, NW, Atlanta, GA 30332 FESCCAESD Kenneth David Lyons Improving Energy Efficiency of Air...

  7. Curriculum Vitae Hans Ulrich Walther

    E-Print Network [OSTI]

    2015-08-17

    Aug 15, 2015 ... Algebra/Topology seminar, Georgia Tech, Atlanta, GA (November 2010). ... AMS Sectional Meeting, Columbia University, New York, New York ...

  8. Bulletin of Mathematical Biology (2008) 70: 460483 DOI 10.1007/s11538-007-9264-3

    E-Print Network [OSTI]

    Newman, Stuart A.

    2008-01-01

    University, Atlanta, GA 30322-2430, USA d Polish Academy of Sciences, Institute of Fundamental Technological development · Chondrogenesis · Mesenchymal condensation · Reaction­diffusion model 1. Introduction The growth

  9. Bulletin of Mathematical Biology (2007) DOI 10.1007/s11538-007-9264-3

    E-Print Network [OSTI]

    Zhang, Yong-Tao

    2007-01-01

    University, Atlanta, GA 30322-2430, USA d Polish Academy of Sciences, Institute of Fundamental Technological development · Chondrogenesis · Mesenchymal condensation · Reaction­diffusion model 1. Introduction The growth

  10. Development of a Residential Integrated Ventilation Controller

    E-Print Network [OSTI]

    Walker, Iain

    2013-01-01

    Refrigerating, and Air-Conditioning Engineers, Atlanta, GA.Refrigerating and Air-Conditioning Engineers. November,Control. ” Heating Air Conditioning and Refrigeration News.

  11. Building America Technology Solutions for New and Existing Homes...

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

    case study describes the construction of a new test home in Atlanta, GA, that demonstrates current best practices for the mixed-humid climate, including a building envelope...

  12. TYPICAL HOT WATER DRAW PATTERNS BASED ON FIELD DATA

    E-Print Network [OSTI]

    Lutz, Jim

    2014-01-01

    for Rating Residential Water Heaters. Atlanta, GA: ASHRAE,Procedures for Residential Water Heaters, Direct HeatingY. Qin, and M. Melody. "Hot Water Draw Patterns in Single-

  13. Future Scientific Directions: Coupling between land ecosystems and the atmospheric hydrologic cycle through biogenic aerosol pathways

    E-Print Network [OSTI]

    Nenes, Athanasios

    , College Station, TX Robert Griffin University of New Hampshire, Durham, NH Michael Hannigan University Athanasios Nenes Georgia Institute of Technology, Atlanta, GA Mark Potosnak National Center for Atmospheric

  14. QER- Comment of Stephen Arthur 1

    Broader source: Energy.gov [DOE]

    Good morning, I simply was curious if the Atlanta, GA meeting on Business/Economic Development was still on schedule and going to take place?

  15. 332 BlJLldETIN O F THE UNITED STATES FISH COMMISSION. Wheeler, L. T., Corsicann, Navnrro Co., Tex ._._...._.._._........_._...--__.106

    E-Print Network [OSTI]

    ., Atlanta, Fultoii Co., Ga. _....~ ___._____._____..____...._._.__.165 Withers, Robt. E.,Wytheville, Wythe .___.__..._.._.._....___.____.194 Wright, Ab01 A.,Griffin, Spnlding Co., Ge -__.-..___.__-.-- -- -.__-.-.__....160,231 Wright, 13. B

  16. THE EFFECT OF CIRCUMSOLAR RADIATION ON THE ACCURACY OF PYRHELIOMETER MEASUREMENTS OF THE DIRECT SOLAR RADIATION

    E-Print Network [OSTI]

    Grether, D.

    2012-01-01

    of the International Solar Energy Society, Philadelphia, PA,of the International Solar Energy Society, Atlanta, Ga. ,of the International Solar Energy Society, Phoenix, Ariz. ,

  17. The Continuous Time Service Network Design Problem

    E-Print Network [OSTI]

    2015-01-02

    ... School of Industrial & Systems Engineering, Georgia Institute of Technology, Atlanta, GA ... Fast shipping times (and low cost) are critical to the success of.

  18. A 3-10 GHZLCR-matched Power Amplifier using Flip-Chip Mounted AlGaN/GaN HEMTs

    E-Print Network [OSTI]

    York, Robert A.

    amplifier using GaN- HEMTs-on-Sapphire. I INTRODUCTION GaN HEMTs have enormous potential for realizing high-power Traveling Wave Power Amplifier circuit (TWPA)[1][2] for realization of wideband power amplifiersWE4A-5 A 3-10 GHZLCR-matched Power Amplifier using Flip-Chip Mounted AlGaN/GaN HEMTs Jane J

  19. Intermixing of InGaAs/GaAs Quantum Well Using Multiple Cycles Annealing Cu-doped SiO2

    SciTech Connect (OSTI)

    Hongpinyo, V; Ding, Y H; Dimas, C E; Wang, Y; Ooi, B S; Qiu, W; Goddard, L L; Behymer, E M; Cole, G D; Bond, T C

    2008-06-11

    The authors investigate the effect of intermixing in InGaAs/GaAs quantum well structure using Cu-doped SiO{sub 2}. The incorporation of Cu into the silica film yields larger bandgap shift than typical impurity-free vacancy diffusion (IFVD) method at a lower activation temperature. We also observe enhancement of the photoluminescence (PL) signal from the intermixed InGaAs/GaAs quantum well structure after being cycle-annealed at 850 C.

  20. Metamorphic GaAsP buffers for growth of wide-bandgap InGaP solar cells J. Simon,1,a

    E-Print Network [OSTI]

    Haller, Gary L.

    . INTRODUCTION Triple-junction metamorphic solar cells have reached ef- ficiencies as high as 41.1% by combiningMetamorphic GaAsP buffers for growth of wide-bandgap InGaP solar cells J. Simon,1,a S. Tomasulo,1 P-yP solar cells. Tensile-strained GaAsxP1-x buffers grown on GaAs using unoptimized conditions

  1. FIRST DEMONSTRATION OF MONOLITHIC InP-BASED InAlAs/InGaAsP/InGaAs TRIPLE JUNCTION SOLAR CELLS

    E-Print Network [OSTI]

    Atwater, Harry

    FIRST DEMONSTRATION OF MONOLITHIC InP-BASED InAlAs/InGaAsP/InGaAs TRIPLE JUNCTION SOLAR CELLS RobynAlAs/InGaAsP/InGaAs triple junction solar cell grown on InP substrate. X-ray diffraction characterization shows high quality solar cell materials. Preliminary 1-sun AM1.5D testing of the triple junction solar cell shows promising

  2. Office of the Chief Information Officer | Department of Energy

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

    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 Delicious Rank EERE: Alternative Fuelsof EnergyApril 2014DepartmentCouncilOffice of the Chief Financial

  3. Characterization of Cu(In,Ga)Se2 (CIGS) films with varying gallium ratios

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

    Claypoole, Jesse; Peace, Bernadette; Sun, Neville; Dwyer, Dan; Eisaman, Matthew D.; Haldar, Pradeep; Efstathiadis, Harry

    2015-09-05

    Cu(In1-x,Gax)Se2 (CIGS) absorber layers were deposited on molybdenum (Mo) coated soda-lime glass substrates with varying Ga content (described as Ga/(In+Ga) ratios) with respect to depth. As the responsible mechanisms for the limitation of the performance of the CIGS solar cells with high Ga contents are not well understood, the goal of this work was to investigate different properties of CIGS absorber films with Ga/(In+Ga) ratios varied between 0.29 and 0.41 (as determined by X-ray florescence spectroscopy (XRF)) in order to better understand the role that the Ga content has on film quality. The Ga grading in the CIGS layer hasmore »the effect causing a higher bandgap toward the surface and Mo contact while the band gap in the middle of the CIGS layer is lower. Also, a wider and larger Ga/(In+Ga) grading dip located deeper in the CIGS absorber layers tend to produce larger grains in the regions of the films that have lower Ga/(In+Ga) ratios. It was found that surface roughness decreases from 51.2 nm to 41.0 nm with increasing Ga/(In+Ga) ratios. However, the surface roughness generally decreases if the Ga grading occurs deeper in the absorber layer.« less

  4. Radiation damage of GaAs thin-film solar cells on Si substrates

    SciTech Connect (OSTI)

    Itoh, Y.; Yamaguchi, M.; Nishioka, T.; Yamamoto, A.

    1987-01-15

    1-MeV electron irradiation damages in GaAs thin-film solar cells on Si substrates are examined for the first time. Damage constant for minority-carrier diffusion length in GaAs heteroepitaxial films on Si substrates is found to be the same as that in GaAs homoepitaxial films on GaAs substrates. This agreement suggests that GaAs/Si has the same defect introduction rate with radiation as GaAs/GaAs. The degradation of GaAs solar cells on Si with electron irradiation is less than that of GaAs solar cells on GaAs, because in the present, GaAs films on Si substrates have lower minority-carrier diffusion length compared to GaAs films on GaAs and these films are insensitive to radiation. The p/sup +/-p/sup +/-n AlGaAs-GaAs heteroface solar cell with junction depth of about 0.3 ..mu..m is concluded to be useful for a high-efficiency and radiation-resistant solar cell fabricated on a Si substrate.

  5. Laser Gain and Threshold Properties in Compressive-Strained and Lattice-Matched GaInNAs/GaAs Quantum Wells

    SciTech Connect (OSTI)

    Chow, W.W.; Jones, E.D.; Modine, N.A.; Allerman, A.A.; Kurtz, S.R.

    1999-08-04

    The optical gain spectra for compressive-strained and lattice-matched GaInNAs/GaAs quantum wells are computed using a microscopic laser theory. From these spectra, the peak gain and carrier radiative decay rate as functions of carrier density are determined. These dependences allow the study of lasing threshold current density for different GAInNAs/GaAs laser structures.

  6. Metal contacts on ZnSe and GaN

    SciTech Connect (OSTI)

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

    1997-05-01

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

  7. Vehicle Technologies Office Merit Review 2014: Vehicle & Systems...

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

    Vehicle Technologies Office Merit Review 2014: Vehicle & Systems Simulation & Testing Vehicle Technologies Office Merit Review 2014: Vehicle & Systems Simulation & Testing...

  8. Advanced Manufacturing Office, U.S. Department of Energy

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

    materials Advanced Manufacturing Office Advanced Manufacturing Office Battery and Supercapacitors: A technology capable of transforming many industries including vehicles systems...

  9. Contribution of alloy clustering to limiting the two-dimensional electron gas mobility in AlGaN/GaN and InAlN/GaN heterostructures: Theory and experiment

    SciTech Connect (OSTI)

    Ahmadi, Elaheh; Mishra, Umesh K. [Electrical and Computer Engineering Department, University of California, Santa Barbara, California 93106 (United States); Chalabi, Hamidreza [Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305 (United States); Kaun, Stephen W.; Shivaraman, Ravi; Speck, James S. [Materials Department, University of California, Santa Barbara, California 93106 (United States)

    2014-10-07

    The influence of alloy clustering on fluctuations in the ground state energy of the two-dimensional electron gas (2DEG) in AlGaN/GaN and InAlN/GaN heterostructures is studied. We show that because of these fluctuations, alloy clustering degrades the mobility even when the 2DEG wavefunction does not penetrate the alloy barrier unlike alloy disorder scattering. A comparison between the results obtained for AlGaN/GaN and InAlN/GaN heterostructures shows that alloy clustering limits the 2DEG mobility to a greater degree in InAlN/GaN heterostructures. Our study also reveals that the inclusion of an AlN interlayer increases the limiting mobility from alloy clustering. Moreover, Atom probe tomography is used to demonstrate the random nature of the fluctuations in the alloy composition.

  10. Chicago Operations Office: Technology summary

    SciTech Connect (OSTI)

    Not Available

    1994-12-01

    This document has been prepared by the Department of Energy`s (DOE) Environmental Management (EM) Office of Technology Development (OTD) to highlight its research, development, demonstration, testing, and evaluation (RDDT and E) activities funded through the Chicago Operations Office. Technologies and processes described have the potential to enhance DOE`s cleanup and waste management efforts, as well as improve US Industry`s competitiveness in global environmental markets. The information has been assembled from recently produced OTD documents which highlight technology development activities within each of the OTD program elements. OTD technologies addresses three specific problem areas: (1) groundwater and soils cleanup; (2) waste retrieval and processing; and (3) pollution prevention. These problems are not unique to DOE, but are associated with other Federal agency and industry sites as well. Thus, technical solutions developed within OTD programs will benefit DOE, and should have direct applications in outside markets.

  11. Nano-scale luminescence characterization of individual InGaN/GaN quantum wells stacked in a microcavity using scanning transmission electron microscope cathodoluminescence

    SciTech Connect (OSTI)

    Schmidt, Gordon Müller, Marcus; Veit, Peter; Bertram, Frank; Christen, Jürgen; Glauser, Marlene; Carlin, Jean-François; Cosendey, Gatien; Butté, Raphaël; Grandjean, Nicolas

    2014-07-21

    Using cathodoluminescence spectroscopy directly performed in a scanning transmission electron microscope at liquid helium temperatures, the optical and structural properties of a 62 InGaN/GaN multiple quantum well embedded in an AlInN/GaN based microcavity are investigated at the nanometer scale. We are able to spatially resolve a spectral redshift between the individual quantum wells towards the surface. Cathodoluminescence spectral linescans allow directly visualizing the critical layer thickness in the quantum well stack resulting in the onset of plastic relaxation of the strained InGaN/GaN system.

  12. Active region based on graded-gap InGaN/GaN superlattices for high-power 440- to 470-nm light-emitting diodes

    SciTech Connect (OSTI)

    Tsatsulnikov, A. F., E-mail: Andrew@beam.ioffe.ru; Lundin, W. V.; Sakharov, A. V.; Zavarin, E. E.; Usov, S. O.; Nikolaev, A. E.; Cherkashin, N. A.; Ber, B. Ya.; Kazantsev, D. Yu. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation); Mizerov, M. N. [Russian Academy of Sciences, Center for Microelectronics, Ioffe Physicotechnical Institute (Russian Federation); Park, Hee Seok [Samsung Electro-Mechanics Co. Ltd. (Korea, Republic of); Hytch, M.; Hue, F. [National Center for Scientific Research, Center for Material Elaboration and Structural Studies (France)

    2010-01-15

    The structural and optical properties of light-emitting diode structures with an active region based on ultrathin InGaN quantum wells limited by short-period InGaN/GaN superlattices from both sides have been investigated. The dependences of the external quantum efficiency on the active region design are analyzed. It is shown that the use of InGaN/GaN structures as limiting graded-gap short-period superlattices may significantly increase the quantum efficiency.

  13. Graphene/GaN diodes for ultraviolet and visible photodetectors

    SciTech Connect (OSTI)

    Lin, Fang; Chen, Shao-Wen; Meng, Jie; Tse, Geoffrey; Fu, Xue-Wen; Xu, Fu-Jun [State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871 (China); Shen, Bo; Liao, Zhi-Min, E-mail: liaozm@pku.edu.cn, E-mail: yudp@pku.edu.cn; Yu, Da-Peng, E-mail: liaozm@pku.edu.cn, E-mail: yudp@pku.edu.cn [State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter, Beijing (China)

    2014-08-18

    The Schottky diodes based on graphene/GaN interface are fabricated and demonstrated for the dual-wavelength photodetection of ultraviolet (UV) and green lights. The physical mechanisms of the photoelectric response of the diodes with different light wavelengths are different. For UV illumination, the photo-generated carriers lower the Schottky barrier and increase the photocurrent. For green light illumination, as the photon energy is smaller than the bandgap of GaN, the hot electrons excited in graphene via internal photoemission are responsible for the photoelectric response. Using graphene as a transparent electrode, the diodes show a ?mS photoresponse, providing an alternative route toward multi-wavelength photodetectors.

  14. Polycrystalline MBE-grown GaAs for solar cells

    SciTech Connect (OSTI)

    Friedman, D.J.; Kurtz, S.R.; Kibbler, A.E.; Al-Jassim, M.; Jones, K.; Keyes, B.; Matson, R.

    1997-02-01

    This paper will discuss initial studies of thin-film GaAs grown by molecular-beam epitaxy for use in developing a thin-film GaAs solar cell. Photocurrent and photoluminescence intensity are related to the material morphology as a function of growth conditions. Growth temperature and V/III ratio have a dramatic effect on the photocurrent. However, it seems likely that even after optimizing such growth parameters, it will be necessary to provide substrates that can provide templates to enhance grain size from the start of thin-film growth. {copyright} {ital 1997 American Institute of Physics.}

  15. Polycrystalline MBE-grown GaAs for solar cells

    SciTech Connect (OSTI)

    Friedman, D. J.; Kurtz, Sarah R.; Kibbler, A. E.; Al-Jassim, M.; Jones, K.; Keyes, B.; Matson, R.

    1997-02-15

    This paper will discuss initial studies of thin-film GaAs grown by molecular-beam epitaxy for use in developing a thin-film GaAs solar cell. Photocurrent and photoluminescence intensity are related to the material morphology as a function of growth conditions. Growth temperature and V/III ratio have a dramatic effect on the photocurrent. However, it seems likely that even after optimizing such growth parameters, it will be necessary to provide substrates that can provide templates to enhance grain size from the start of thin-film growth.

  16. Highly transparent ammonothermal bulk GaN substrates

    SciTech Connect (OSTI)

    Jiang, WK; Ehrentraut, D; Downey, BC; Kamber, DS; Pakalapati, RT; Do Yoo, H; D'Evelyn, MP

    2014-10-01

    A novel apparatus has been employed to grow ammonothermal (0001) gallium nitride (GaN) with diameters up to 2 in The crystals have been characterized by x-ray diffraction rocking-curve (XRC) analysis, optical and scanning electron microscopy (SEM), cathodoluminescence (CL), and optical spectroscopy. High crystallinity GaN with FWHM values about 20-50 arcsec and dislocation densities below 1 x 10(5) cm(-2) have been obtained. High optical transmission was achieved with an optical absorption coefficient below 1 cm(-1) at a wavelength of 450 nm. (C) 2014 Elsevier B.V. All rights reserved.

  17. A hole modulator for InGaN/GaN light-emitting diodes Zi-Hui Zhang, Zabu Kyaw, Wei Liu, Yun Ji, Liancheng Wang, Swee Tiam Tan, Xiao Wei Sun, and Hilmi Volkan

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    well on optical power of light-emitting diodes Appl. Phys. Lett. 96, 051113 (2010); 10-emitting diodes (LEDs) due to the ineffective hole injection into the InGaN/GaN multiple quantum well (MQW) active in the p-GaN layer can be enhanced. Furthermore, the hole modulator is adopted in the InGaN/GaN LEDs, which

  18. Office of Executive Resources Office of the Chief Human Capital Officer

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

    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 Delicious RankADVANCED MANUFACTURINGEnergy Bills and ReduceNovemberDOE's PrioritiesOctober 2013 NewsOctober Office of

  19. Office of Executive Resources Office of the Chief Human Capital Officer

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

    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 Delicious RankADVANCED MANUFACTURINGEnergy Bills and ReduceNovemberDOE's PrioritiesOctober 2013 NewsOctober Office of

  20. Office of Executive Resources Office of the Chief Human Capital Officer

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

    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 Delicious RankADVANCED MANUFACTURINGEnergy Bills and ReduceNovemberDOE's PrioritiesOctober 2013CommentsOffice of

  1. Office of Executive Resources Office of the Chief Human Capital Officer

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

    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 Delicious RankADVANCED MANUFACTURINGEnergy Bills and ReduceNovemberDOE's PrioritiesOctober 2013CommentsOffice

  2. Strong enhancement of terahertz emission from GaAs in InAs/GaAs quantum dot structures

    SciTech Connect (OSTI)

    Estacio, Elmer; Pham, Minh Hong; Takatori, Satoru; Cadatal-Raduban, Marilou; Nakazato, Tomoharu; Shimizu, Toshihiko; Sarukura, Nobuhiko; Somintac, Armando; Defensor, Michael; Awitan, Fritz Christian B.; Jaculbia, Rafael B.; Salvador, Arnel; Garcia, Alipio

    2009-06-08

    We report on the intense terahertz emission from InAs/GaAs quantum dot (QD) structures grown by molecular beam epitaxy. Results reveal that the QD sample emission was as high as 70% of that of a p-type InAs wafer, the most intense semiconductor emitter to date. Excitation wavelength studies showed that the emission was due to absorption in strained undoped GaAs, and corresponds to a two order-of-magnitude enhancement. Moreover, it was found that multilayer QDs emit more strongly compared with a single layer QD sample. At present, we ascribe the intense radiation to huge strain fields at the InAs/GaAs interface.

  3. Characteristics of InGaP/InGaAs pseudomorphic high electron mobility transistors with triple delta-doped sheets

    SciTech Connect (OSTI)

    Chu, Kuei-Yi; Chiang, Meng-Hsueh Cheng, Shiou-Ying; Liu, Wen-Chau

    2012-02-15

    Fundamental and insightful characteristics of InGaP/InGaAs double channel pseudomorphic high electron mobility transistors (DCPHEMTs) with graded and uniform triple {delta}-doped sheets are coomprehensively studied and demonstrated. To gain physical insight, band diagrams, carrier densities, and direct current characteristics of devices are compared and investigated based on the 2D semiconductor simulator, Atlas. Due to uniform carrier distribution and high electron density in the double InGaAs channel, the DCPHEMT with graded triple {delta}-doped sheets exhibits better transport properties, higher and linear transconductance, and better drain current capability as compared with the uniformly triple {delta}-doped counterpart. The DCPHEMT with graded triple {delta}-doped structure is fabricated and tested, and the experimental data are found to be in good agreement with simulated results.

  4. Terahertz intersubband absorption in non-polar m-plane AlGaN/GaN quantum wells

    SciTech Connect (OSTI)

    Edmunds, C.; Malis, O.; Shao, J.; Shirazi-HD, M.; Manfra, M. J.

    2014-07-14

    We demonstrate THz intersubband absorption (15.6–26.1?meV) in m-plane AlGaN/GaN quantum wells. We find a trend of decreasing peak energy with increasing quantum well width, in agreement with theoretical expectations. However, a blue-shift of the transition energy of up to 14?meV was observed relative to the calculated values. This blue-shift is shown to decrease with decreasing charge density and is, therefore, attributed to many-body effects. Furthermore, a??40% reduction in the linewidth (from roughly 8 to 5?meV) was obtained by reducing the total sheet density and inserting undoped AlGaN layers that separate the wavefunctions from the ionized impurities in the barriers.

  5. High-performance broadband optical coatings on InGaN/GaN solar cells for multijunction device integration

    SciTech Connect (OSTI)

    Young, N. G. Farrell, R. M.; Iza, M.; Speck, J. S.; Perl, E. E.; Keller, S.; Bowers, J. E.; Nakamura, S.; DenBaars, S. P.

    2014-04-21

    We demonstrate InGaN/GaN multiple quantum well solar cells grown by metalorganic chemical vapor deposition on a bulk (0001) substrate with high-performance broadband optical coatings to improve light absorption. A front-side anti-reflective coating and a back-side dichroic mirror were designed to minimize front surface reflections across a broad spectral range and maximize rear surface reflections only in the spectral range absorbed by the InGaN, making the cells suitable for multijunction solar cell integration. Application of optical coatings increased the peak external quantum efficiency by 56% (relative) and conversion efficiency by 37.5% (relative) under 1 sun AM0 equivalent illumination.

  6. Office of the Chief Human Capital Officer | Department of Energy

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

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

  7. Office of the Chief Information Officer | Department of Energy

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

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

  8. Office of the Chief Financial Officer Organization Chart | Department of

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

    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 Natural GasAdjustmentsShirley Ann JacksonDepartment ofOffice|in the subsurfaceSecurityMissionEnergy Efficiency

  9. InGaAs/GaAsP strain balanced multi-quantum wires grown on misoriented GaAs substrates for high efficiency solar cells

    SciTech Connect (OSTI)

    Alonso-Álvarez, D.; Thomas, T.; Führer, M.; Hylton, N. P.; Ekins-Daukes, N. J.; Lackner, D.; Philipps, S. P.; Bett, A. W.; Sodabanlu, H.; Fujii, H.; Watanabe, K.; Sugiyama, M.; Nasi, L.; Campanini, M.

    2014-08-25

    Quantum wires (QWRs) form naturally when growing strain balanced InGaAs/GaAsP multi-quantum wells (MQW) on GaAs [100] 6° misoriented substrates under the usual growth conditions. The presence of wires instead of wells could have several unexpected consequences for the performance of the MQW solar cells, both positive and negative, that need to be assessed to achieve high conversion efficiencies. In this letter, we study QWR properties from the point of view of their performance as solar cells by means of transmission electron microscopy, time resolved photoluminescence and external quantum efficiency (EQE) using polarised light. We find that these QWRs have longer lifetimes than nominally identical QWs grown on exact [100] GaAs substrates, of up to 1??s, at any level of illumination. We attribute this effect to an asymmetric carrier escape from the nanostructures leading to a strong 1D-photo-charging, keeping electrons confined along the wire and holes in the barriers. In principle, these extended lifetimes could be exploited to enhance carrier collection and reduce dark current losses. Light absorption by these QWRs is 1.6 times weaker than QWs, as revealed by EQE measurements, which emphasises the need for more layers of nanostructures or the use light trapping techniques. Contrary to what we expected, QWR show very low absorption anisotropy, only 3.5%, which was the main drawback a priori of this nanostructure. We attribute this to a reduced lateral confinement inside the wires. These results encourage further study and optimization of QWRs for high efficiency solar cells.

  10. OFFICE,

    Office of Legacy Management (LM)

    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 NaturalDukeWakefield Municipal Gas &SCE-SessionsSouth DakotaRobbins and700 GJO-2003-411-TAC GJO-PIN~$ ., .,. ' e' , U .S

  11. 1.9 kV AlGaN/GaN Lateral Schottky Barrier Diodes on Silicon

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

    Zhu, Mingda [University of Notre Dame, IN (United States); Song, Bo [Cornell University, Ithaca, NY (United States); Qi, Meng [University of Notre Dame, IN (United States); Hu, Zongyang [University of Notre Dame, IN (United States); Nomoto, Kazuki [University of Notre Dame, IN (United States); Yan, Xiaodong [University of Notre Dame, IN (United States); Cao, Yu [IQE, Westborough, MA (United States); Johnson, Wayne [IQE, Westborough, MA (United States); Kohn, Erhard [University of Notre Dame, IN (United States); Jena, Debdeep [Cornell University, Ithaca, NY (United States); Xing, Grace Huili [Cornell University, Ithaca, NY (United States)

    2015-04-01

    In this letter, we present AlGaN/GaN lateral Schottky barrier diodes on silicon with recessed anodes and dual field plates. A low specific on-resistance RON,SP (5.12 m?{center_dot}cm2), a low turn-on voltage (1.9 kV), were simultaneously achieved in devices with a 25 ?m anode/cathode separation, resulting in a power figure-of-merit (FOM) BV2/RON,SP of 727 MW{center_dot}cm2. The record high breakdown voltage of 1.9 kV is attributed to the dual field plate structure.

  12. Electrically pumped single-photon emission at room temperature from a single InGaN/GaN quantum dot

    SciTech Connect (OSTI)

    Deshpande, Saniya; Frost, Thomas; Hazari, Arnab; Bhattacharya, Pallab, E-mail: pkb@eecs.umich.edu [Center for Photonics and Multiscale Nanomaterials, Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Avenue, Ann Arbor, Michigan 48109 (United States)

    2014-10-06

    We demonstrate a semiconductor quantum dot based electrically pumped single-photon source operating at room temperature. Single photons emitted in the red spectral range from single In{sub 0.4}Ga{sub 0.6}N/GaN quantum dots exhibit a second-order correlation value g{sup (2)}(0) of 0.29, and fast recombination lifetime ?1.3 ±0.3 ns at room temperature. The single-photon source can be driven at an excitation repetition rate of 200?MHz.

  13. 1.9 kV AlGaN/GaN Lateral Schottky Barrier Diodes on Silicon

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

    Zhu, Mingda; Song, Bo; Qi, Meng; Hu, Zongyang; Nomoto, Kazuki; Yan, Xiaodong; Cao, Yu; Johnson, Wayne; Kohn, Erhard; Jena, Debdeep; et al

    2015-02-16

    In this letter, we present AlGaN/GaN lateral Schottky barrier diodes on silicon with recessed anodes and dual field plates. A low specific on-resistance RON,SP (5.12 m? · cm2), a low turn-on voltage (1.9 kV), were simultaneously achieved in devices with a 25 ?m anode/cathode separation, resulting in a power figure-of-merit (FOM) BV2/RON,SP of 727 MW·cm2. The record high breakdown voltage of 1.9 kV is attributed to the dual field plate structure.

  14. Theory of weak localization in ferromagnetic (Ga,Mn)As 

    E-Print Network [OSTI]

    Garate, Ion; Sinova, Jairo; Jungwirth, T.; MacDonald, A. H.

    2009-01-01

    We study quantum interference corrections to the conductivity in (Ga,Mn)As ferromagnetic semiconductors using a model with disordered valence-band holes coupled to localized Mn moments through a p-d kinetic-exchange interaction. We find that at Mn...

  15. Low-temperature magnetization of (Ga,Mn) As semiconductors 

    E-Print Network [OSTI]

    Jungwirth, T.; Masek, J.; Wang, KY; Edmonds, KW; Sawicki, M.; Polini, M.; Sinova, Jairo; MacDonald, AH; Campion, RP; Zhao, LX; Farley, NRS; Johal, TK; van der Laan, G.; Foxon, CT; Gallagher, BL.

    2006-01-01

    the semiphenomenological virtual crystal model the valence band holes experience a mean-field hMF =JpdNMn?S , and the band Hamiltonian can then be written as H? MF=H? KL?B?+hMFs?z, where H? KL?B? is the B-dependent six- band Kohn-Luttinger Hamiltonian of the GaAs host...

  16. Ohmic contacts for high-temperature GaP devices 

    E-Print Network [OSTI]

    Van der Hoeven, Willem Bernard

    1981-01-01

    in Table II, heat treatments have also been made by laser. One of the earliest papers that describe laser annealing to obtain ohmic contacts to GaP appeared in 1974 (20] . In this paper, Pounds, Saifi, and Hahm reported to have obtained ohmic contacts...

  17. High-quality InP on GaAs

    E-Print Network [OSTI]

    Quitoriano, Nathaniel Joseph

    2006-01-01

    In addition to traditional telecommunication applications, devices based on InP have received increased attention for high-performance electronics. InP growth on GaAs is motivated by the fact that InP wafers are smaller, ...

  18. Nanoscale GaAs metalsemiconductormetal photodetectors fabricated using nanoimprint lithography

    E-Print Network [OSTI]

    ­V) characteristics of the contacts are very sensi- tive to the surface states and defects. In this letter, we report mold with interdigited fin- gers was first created on a silicon substrate. Next, a layer of polymethylmethancrylate PMMA was spun on a semi- insulating SI GaAs substrate. Before imprinting, both the mold

  19. Properties of H, O and C in GaN

    SciTech Connect (OSTI)

    Pearton, S.J.; Abernathy, C.R.; Lee, J.W.

    1996-04-01

    The electrical properties of the light ion impurities H, O and C in GaN have been examined in both as-grown and implanted material. H is found to efficiently passivate acceptors such as Mg, Ca and C. Reactivation occurs at {ge} 450 C and is enhanced by minority carrier injection. The hydrogen does not leave the GaN crystal until > 800 C, and its diffusivity is relatively high ({approximately} 10{sup {minus}11} cm{sup 2}/s) even at low temperatures (< 200 C) during injection by wet etching, boiling in water or plasma exposure. Oxygen shows a low donor activation efficiency when implanted into GaN, with an ionization level of 30--40 meV. It is essentially immobile up to 1,100 C. Carbon can produce low p-type levels (3 {times} 10{sup 17} cm{sup {minus}3}) in GaN during MOMBE, although there is some evidence it may also create n-type conduction in other nitrides.

  20. Carlsbad Area Office strategic plan

    SciTech Connect (OSTI)

    NONE

    1995-10-01

    This edition of the Carlsbad Area Office Strategic Plan captures the U.S. Department of Energy`s new focus, and supercedes the edition issued previously in 1995. This revision reflects a revised strategy designed to demonstrate compliance with environmental regulations earlier than the previous course of action; and a focus on the selected combination of scientific investigations, engineered alternatives, and waste acceptance criteria for supporting the compliance applications. An overview of operations and historical aspects of the Waste Isolation Pilot Plant near Carlsbad, New Mexico is presented.

  1. Budget Office | The Ames Laboratory

    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 PublicationsAudits &Bradbury Science Museum -Brooklin Gore About--BuckleBudget Office

  2. Ombuds Office Location & Hours

    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 NewsInformationJesseworkSURVEY UNIVERSEHowScientificOmbuds Office Location & Hours Ombuds

  3. DOE Loan Programs Office Update

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

    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 Natural GasAdjustmentsShirleyEnergy A plug-in electric vehicle10nominate anDepartment ofTraining|Loan Programs Office

  4. Luminescence properties of defects in GaN

    SciTech Connect (OSTI)

    Reshchikov, Michael A.; Morkoc, Hadis [Department of Electrical Engineering and Physics Department, Virginia Commonwealth University, Richmond, Virginia 23284 (United States)

    2005-03-15

    Gallium nitride (GaN) and its allied binaries InN and AIN as well as their ternary compounds have gained an unprecedented attention due to their wide-ranging applications encompassing green, blue, violet, and ultraviolet (UV) emitters and detectors (in photon ranges inaccessible by other semiconductors) and high-power amplifiers. However, even the best of the three binaries, GaN, contains many structural and point defects caused to a large extent by lattice and stacking mismatch with substrates. These defects notably affect the electrical and optical properties of the host material and can seriously degrade the performance and reliability of devices made based on these nitride semiconductors. Even though GaN broke the long-standing paradigm that high density of dislocations precludes acceptable device performance, point defects have taken the center stage as they exacerbate efforts to increase the efficiency of emitters, increase laser operation lifetime, and lead to anomalies in electronic devices. The point defects include native isolated defects (vacancies, interstitial, and antisites), intentional or unintentional impurities, as well as complexes involving different combinations of the isolated defects. Further improvements in device performance and longevity hinge on an in-depth understanding of point defects and their reduction. In this review a comprehensive and critical analysis of point defects in GaN, particularly their manifestation in luminescence, is presented. In addition to a comprehensive analysis of native point defects, the signatures of intentionally and unintentionally introduced impurities are addressed. The review discusses in detail the characteristics and the origin of the major luminescence bands including the ultraviolet, blue, green, yellow, and red bands in undoped GaN. The effects of important group-II impurities, such as Zn and Mg on the photoluminescence of GaN, are treated in detail. Similarly, but to a lesser extent, the effects of other impurities, such as C, Si, H, O, Be, Mn, Cd, etc., on the luminescence properties of GaN are also reviewed. Further, atypical luminescence lines which are tentatively attributed to the surface and structural defects are discussed. The effect of surfaces and surface preparation, particularly wet and dry etching, exposure to UV light in vacuum or controlled gas ambient, annealing, and ion implantation on the characteristics of the defect-related emissions is described.

  5. Testing a GaAs cathode in SRF gun

    SciTech Connect (OSTI)

    Wang, E.; Kewisch, J.; Ben-Zvi, I.; Burrill, A.; Rao, T.; Wu, Q.; Holmes, D.

    2011-03-28

    RF electron guns with a strained superlattice GaAs cathode are expected to generate polarized electron beams of higher brightness and lower emittance than do DC guns, due to their higher field gradient at the cathode's surface and lower cathode temperature. We plan to install a bulk GaAs:Cs in a SRF gun to evaluate the performance of both the gun and the cathode in this environment. The status of this project is: In our 1.3 GHz 1/2 cell SRF gun, the vacuum can be maintained at nearly 10{sup -12} Torr because of cryo-pumping at 2K. With conventional activation of bulk GaAs, we obtained a QE of 10% at 532 nm, with lifetime of more than 3 days in the preparation chamber and have shown that it can survive in transport from the preparation chamber to the gun. The beam line has been assembled and we are exploring the best conditions for baking the cathode under vacuum. We report here the progress of our test of the GaAs cathode in the SRF gun. Future particle accelerators, such as eRHIC and the ILC require high-brightness, high-current polarized electrons. Strained superlattice GaAs:Cs has been shown to be an efficient cathode for producing polarized electrons. Activation of GaAs with Cs,O(F) lowers the electron affinity and makes it energetically possible for all the electrons, excited into the conduction band that drift or diffuse to the emission surface, to escape into the vacuum. Presently, all operating polarized electron sources, such as the CEBAF, are DC guns. In these devices, the excellent ultra-high vacuum extends the lifetime of the cathode. However, the low field gradient on the photocathode's emission surface of the DC guns limits the beam quality. The higher accelerating gradients, possible in the RF guns, generate a far better beam. Until recently, most RF guns operated at room temperature, limiting the vacuum to {approx}10{sup -9} Torr. This destroys the GaAs's NEA surface. The SRF guns combine the excellent vacuum conditions of DC guns and the high accelerating gradient of the RF guns, potentially offering a long lived cathode with very low emittance. Testing this concept requires preparation of the cathode, transportation to the SRF gun and evaluation of the performance of the cathode and the gun at cryogenic temperatures. In our work at BNL, we successfully activated the bulk GaAs in the preparation chamber. The highest quantum efficient was 10% at 532 nm that fell to 0.5% after 100 hours. We explored three different ways to activate the GaAs. We verified that the GaAs photocathode remains stable for 30 hours in a 10{sup -11} Torr vacuum. Passing the photocathode through the low 10{sup -9} Torr transfer section in several seconds caused the QE to drop to 0.8%. The photocathode with 0.8% QE can be tested for the SRF gun. The gun and beam pipe were prepared and assembled. After baking at 200 C baking, the vacuum of the gun and beam pipe can sustain a low 10{sup -11} Torr at room temperature. The final test to extract electrons from the gun is ongoing. In this paper, we discuss our progress with this SRF gun and the results of the photocathode in preparation chamber and in magnet transfer line.

  6. Quaternary InGaAsSb Thermophotovoltaic Diodes

    SciTech Connect (OSTI)

    MW Dashiell; JF Beausang; H Ehsani; GJ Nichols; DM Depoy; LR Danielson; P Talamo; KD Rahner; EJ Brown; SR Burger; PM Foruspring; WF Topper; PF Baldasaro; CA Wang; R Huang; M Connors; G Turner; Z Shellenbarger; G Taylor; J Li; R Martinelli; D Donetski; S Anikeev; G Belenky; S Luryi

    2006-03-09

    In{sub x}Ga{sub 1-x}As{sub y}Sb{sub 1-y} thermophotovoltaic (TPV) diodes were grown lattice-matched to GaSb substrates by Metal Organic Vapor Phase Epitaxy (MOVPE) in the bandgap range of E{sub G} = 0.5 to 0.6eV. InGaAsSb TPV diodes, utilizing front-surface spectral control filters, are measured with thermal-to-electric conversion efficiency and power density of {eta}{sub TPV} = 19.7% and PD =0.58 W/cm{sup 2} respectively for a radiator temperature of T{sub radiator} = 950 C, diode temperature of T{sub diode} = 27 C, and diode bandgap of E{sub G} = 0.53eV. Practical limits to TPV energy conversion efficiency are established using measured recombination coefficients and optical properties of front surface spectral control filters, which for 0.53eV InGaAsSb TPV energy conversion is {eta}{sub TPV} = 28% and PD = 0.85W/cm{sup 2} at the above operating temperatures. The most severe performance limits are imposed by (1) diode open-circuit voltage (VOC) limits due to intrinsic Auger recombination and (2) parasitic photon absorption in the inactive regions of the module. Experimentally, the diode V{sub OC} is 15% below the practical limit imposed by intrinsic Auger recombination processes. Analysis of InGaAsSb diode electrical performance vs. diode architecture indicate that the V{sub OC} and thus efficiency is limited by extrinsic recombination processes such as through bulk defects.

  7. Evaluation of Energy Concepts for Office Buildings 

    E-Print Network [OSTI]

    Fisch, M.; Norbert, M.; Plesser, S.

    2005-01-01

    synonym for innovative office buildings in Germany over the last 10 years. Since almost no reliable results of measurement and verification have been made public on the performance of these buildings – often very prominent company headquarters... buildings and analysed existing data on energy consumption suggest that glassed office buildings do not generally have a significantly higher energy consumption than regular office buildings. Introduction Over the last 10 years, some research...

  8. Remarkably reduced efficiency droop by using staircase thin InGaN quantum barriers in InGaN based blue light emitting diodes

    SciTech Connect (OSTI)

    Zhou, Kun; Ikeda, Masao, E-mail: mikeda2013@sinano.ac.cn, E-mail: jpliu2010@sinano.ac.cn; Liu, Jianping, E-mail: mikeda2013@sinano.ac.cn, E-mail: jpliu2010@sinano.ac.cn; Zhang, Shuming; Li, Deyao; Zhang, Liqun; Yang, Hui [Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou (China); Key Laboratory of Nanodevices and Applications, Chinese Academy of Sciences, Suzhou (China); Cai, Jin; Wang, Hui; Wang, H. B. [Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou (China); Key Laboratory of Nanodevices and Applications, Chinese Academy of Sciences, Suzhou (China); Suzhou Nanojoin Photonics Co., Ltd., Suzhou (China)

    2014-10-27

    The efficiency droop of InGaN/GaN(InGaN) multiple quantum well (MQW) light emitting diodes (LEDs) with thin quantum barriers (QB) is studied. With thin GaN QB (3?nm–6?nm thickness), the efficiency droop is not improved, which indicates that hole transport cannot be significantly enhanced by the thin GaN QBs. On the contrary, the efficiency droop was remarkably reduced by using a InGaN staircase QB (InGaN SC-QB) MQWs structure where InGaN SC-QBs lower the transport energy barrier of holes. The efficiency droop ratio was as low as 3.3% up to 200?A/cm{sup 2} for the InGaN SC-QB LED. By using monitoring QW with longer wavelength we observe a much uniform carrier distribution in the InGaN SC-QB LEDs, which reveals the mechanism of improvement in the efficiency droop.

  9. 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.

  10. Ergonomic Evaluation for Office Workers Name: Date

    E-Print Network [OSTI]

    Slatton, Clint

    Ergonomic Evaluation for Office Workers Name: Date: Department: Campus Box #: Telephone Number: Fax Number: Building: Room Number: Email Address: Supervisor: Evaluation Date/Time: Symptoms : Respond

  11. Vehicle Technologies Office: Financial Opportunities - Active...

    Office of Environmental Management (EM)

    in the table below. Technology Solicitation Title Open Date Close Date Hydrogen and Fuel Cells Hydrogen and Fuel Cell Technologies Research, Development, and Demonstrations Office...

  12. Vehicle Technologies Office: Advanced Vehicle Testing Activity...

    Energy Savers [EERE]

    (AVTA) Data and Results The Vehicle Technologies Office (VTO) supports work to develop test procedures and carry out testing on a wide range of advanced vehicles and technologies...

  13. Office of Energy Efficiency and Renewable Energy

    Office of Environmental Management (EM)

    energy.govdiversity The Parker Ranch installation in Hawaii Office of Small and Disadvantaged Business Utilization (OSDBU) USWCC ASBCC Energy Connect Network - March 7, 2013...

  14. FBI officer accepts LANL counterintelligence post

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

    LANL counterintelligence FBI officer accepts LANL counterintelligence post Cloyd has most recently served as assistant director of the Counterintelligence Division of the Federal...

  15. Quality New Mexico recognizes Community Programs Office

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

    CPO receives Pion recognition Quality New Mexico recognizes Community Programs Office LANL has received 14 Pion and Roadrunner recognitions from Quality New Mexico since 1997....

  16. Categorical Exclusion Determinations: Office of Energy Efficiency...

    Energy Savers [EERE]

    Energy Efficiency and Renewable Energy Categorical Exclusion Determinations: Office of Energy Efficiency and Renewable Energy Categorical Exclusion Determinations issued by Energy...

  17. Vehicle Technologies Office: 2011 Advanced Power Electronics...

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

    Power Electronics and Electric Motors R&D Annual Progress Report Vehicle Technologies Office: 2011 Advanced Power Electronics and Electric Motors R&D Annual Progress Report The...

  18. Vehicle Technologies Office: 2012 Advanced Power Electronics...

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

    2 Advanced Power Electronics and Electric Motors R&D Annual Progress Report Vehicle Technologies Office: 2012 Advanced Power Electronics and Electric Motors R&D Annual Progress...

  19. Vehicle Technologies Office: 2010 Advanced Power Electronics...

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

    Power Electronics and Electric Motors R&D Annual Progress Report Vehicle Technologies Office: 2010 Advanced Power Electronics and Electric Motors R&D Annual Progress Report The...

  20. Vehicle Technologies Office | Department of Energy

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

    Read more The U.S. Department of Energy's Vehicle Technologies Office supports research, development (R&D), and deployment of efficient and sustainable highway transportation...