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Sample records for ga golden pass

  1. EIS-0501: Golden Pass LNG Export and Pipeline Project, Texas...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    1: Golden Pass LNG Export and Pipeline Project, Texas and Louisiana EIS-0501: Golden Pass LNG Export and Pipeline Project, Texas and Louisiana Summary The Federal Energy Regulatory ...

  2. EIS-0501: Golden Pass LNG Export and Pipeline Project, Texas...

    Energy.gov (indexed) [DOE]

    at the existing Golden Pass liquefied natural gas terminal in Jefferson County, Texas. The proposal includes three new compressor stations in Jefferson and Orange Counties,...

  3. SEMI-ANNUAL REPORTS FOR GOLDEN PASS PRODUCTS LLC - FE DKT. NO...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    GOLDEN PASS PRODUCTS LLC - FE DKT. NO. 12-88-LNG - ORDER 3147 SEMI-ANNUAL REPORTS FOR GOLDEN PASS PRODUCTS LLC - FE DKT. NO. 12-88-LNG - ORDER 3147 PDF icon April 2013 PDF icon ...

  4. EIS-0501: Golden Pass LNG Export Project; Texas and Louisiana | Department

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    of Energy 1: Golden Pass LNG Export Project; Texas and Louisiana EIS-0501: Golden Pass LNG Export Project; Texas and Louisiana Summary The Federal Energy Regulatory Commission (FERC) is analyzing the potential environmental impacts of a proposal to construct and operate: 1) natural gas liquefaction (LNG) and export facilities at the existing Golden Pass LNG Terminal in Jefferson County, Texas; 2) three new compressor stations in Jefferson and Orange Counties, Texas, and Calcasieu Parish,

  5. Golden Pass, TX Natural Gas Liquefied Natural Gas Imports (price) (Dollars

    U.S. Energy Information Administration (EIA) (indexed site)

    per Thousand Cubic Feet) Golden Pass, TX Natural Gas Liquefied Natural Gas Imports (price) (Dollars per Thousand Cubic Feet) Golden Pass, TX Natural Gas Liquefied Natural Gas Imports (price) (Dollars per Thousand Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 2000's -- -- -- 2010's 7.90 5.36 -- -- -- -- - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016

  6. EA-1971: Golden Pass LNG Export and Pipeline Project, Texas and Louisiana

    Energy.gov [DOE]

    The Federal Energy Regulatory Commission (FERC), with DOE as a cooperating agency, announced its intent to prepare an EA to analyze the potential environmental impacts of a proposal to construct and operate natural gas liquefaction and export facilities at the existing Golden Pass liquefied natural gas terminal in Jefferson County, Texas. In June 2014, FERC announced that due to changes in the project location and scope, it would prepare an EIS. See DOE/EIS-0501.

  7. Golden Pass, TX Natural Gas Liquefied Natural Gas Imports from Qatar

    U.S. Energy Information Administration (EIA) (indexed site)

    (Million Cubic Feet) from Qatar (Million Cubic Feet) Golden Pass, TX Natural Gas Liquefied Natural Gas Imports from Qatar (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2011 3,902 4,896 4,100 18,487 4,900 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S.

  8. Joe Golden | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Joe Golden About Us Joe Golden - National Energy Technology Laboratory Joe Golden works at the National Energy Technology Laboratory, one of the Department of Energy's 17 National Laboratories. Most Recent Keeping Cool with Carbon Capture Technologies September 2

  9. High Temperature Reverse By-Pass Diodes Bias and Failures | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Reverse By-Pass Diodes Bias and Failures High Temperature Reverse By-Pass Diodes Bias and Failures Presented at the PV Module Reliability Workshop, February 26 - 27 2013, Golden, ...

  10. Ultraviolet band-pass Schottky barrier photodetectors formed by Al-doped ZnO contacts to n-GaN

    SciTech Connect (OSTI)

    Sheu, J.K.; Lee, M.L.; Tun, C.J.; Lin, S.W.

    2006-01-23

    This work prepared Al-doped ZnO(AZO) films using dc sputtering to form Schottky contacts onto GaN films with low-temperature-grown GaN cap layer. Application of ultraviolet photodetector showed that spectral responsivity exhibits a narrow bandpass characteristic ranging from 345 to 375 nm. Moreover, unbiased peak responsivity was estimated to be around 0.12 A/W at 365 nm, which corresponds to a quantum efficiency of around 40%. In our study, relatively low responsivity can be explained by the marked absorption of the AZO contact layer. When the reverse biases were below 5 V, the study revealed that dark currents were well below 5x10{sup -12} A even though the samples were annealed at increased temperatures.

  11. Golden Field Office

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    5 Department of Energy Golden Field Office 1617 Cole Boulevard Golden, Colorado 80401-3393 FINDING OF NO SIGNIFICANT IMPACT UNIVERSITY OF MAINE'S DEEPWATER OFFSHORE FLOATING WIND TURBINE TESTING AND DEMONSTRATION PROJECT - CASTINE DOE/EA-1792-S1 AGENCY: U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy ACTION: Finding of No Significant Impact (FONSI) SUMMARY: The U.S. Department of Energy (DOE) has completed a Supplemental Environmental Assessment (Supplemental EA)

  12. Golden Field Office | Open Energy Information

    Open Energy Information (Open El) [EERE & EIA]

    DOE Golden Field Office) Jump to: navigation, search Name: DOE Golden Field Office Abbreviation: DOE GFO Address: 15013 Denver West Parkway Place: Golden, Colorado Zip: 80401 Phone...

  13. Golden - Local Information | NREL

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    Golden-Local Information This page provides travel information for visitors to the Golden offices and laboratories of the National Renewable Energy Laboratory. Transportation NREL is accessible via bus on the RTD route 20 from Aurora and Denver. Route 20 travels along 20th Avenue and ends at the NREL Education Center. Visit the RTD Web site or call 303-299-6000 to plan your trip or for more information. Visit the Denver International Airport site to find: Car rental agencies Shuttle services,

  14. High-Efficiency GaAs Thin-Film Solar Cell Reliability | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    GaAs Thin-Film Solar Cell Reliability High-Efficiency GaAs Thin-Film Solar Cell Reliability Presented at the PV Module Reliability Workshop, February 26 - 27 2013, Golden, Colorado ...

  15. Golden Laboratories and Offices | NREL

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    NREL's administrative offices and most research laboratories are located at our campus in Golden, Colorado, north of highway I-70 and west of Denver West Boulevard. View...

  16. Golden Opportunity: Noncompliance Determination (2013-SE-1418)

    Energy.gov [DOE]

    DOE issued a Notice of Noncompliance Determination to Golden Opportunity, Inc. finding that freezer models Golden GFC51 and Golden GFC69 do not comport with the energy conservation standards.

  17. Golden Field Office | Open Energy Information

    Open Energy Information (Open El) [EERE & EIA]

    DOE Golden Field Office Abbreviation: DOE GFO Address: 15013 Denver West Parkway Place: Golden, Colorado Zip: 80401 Phone Number: 720-356-1800 ParentHolding Organization: US...

  18. Golden Valley Wind Park | Open Energy Information

    Open Energy Information (Open El) [EERE & EIA]

    Wind Park Jump to: navigation, search Name Golden Valley Wind Park Facility Golden Valley Wind Park Sector Wind energy Facility Type Commercial Scale Wind Facility Status In...

  19. ARM - Instrument - pass

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    govInstrumentspass Documentation PASS : Handbook ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Instrument : Photoacoustic Soot Spectrometer (PASS) Instrument Categories Aerosols General Overview The photoacoustic soot spectrometer (PASS) measures light absorption by aerosol particles. As the particles pass through a laser beam, the absorbed energy heats the particles and in turn the surrounding air, which sets off

  20. Golden Field Office Contacts | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Golden Field Office » Golden Field Office Contacts Golden Field Office Contacts On this page you will find address and contact information for the Golden Field Office of the Office of Energy Efficiency and Renewable Energy (EERE). Mailing Address U.S. Department of Energy Golden Field Office 15013 Denver West Parkway Golden, Colorado 80401 Main Number: 720-356-1800 Main Fax: 720-356-1750 Media Inquiries For media inquiries, please email the EERE communications team at EE.Media@ee.doe.gov.

  1. Golden Cooler: Order (2013-CE-5345)

    Energy.gov [DOE]

    DOE ordered Golden Cooler to pay a $8,000 civil penalty after finding Golden Cooler had failed to certify that certain models of walk-in cooler and freezer components comply with the applicable energy conservation standards.

  2. Golden Field Office | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Golden Field Office Golden Field Office The Golden Field Office was designated a Department of Energy (DOE) field office in December 1992 to provide the Office of Energy Efficiency and Renewable Energy (EERE) with enhanced capability to develop and commercialize renewable energy and energy-efficient technologies. What We Do Golden's mission is to support EERE as its Business Service Center by awarding grants and contracts for clean energy projects, facilitating research and development (R&D)

  3. Golden Annual FOIA Report | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Golden Annual FOIA Report Golden Annual FOIA Report Golden Field Office FY '14 Annual FOIA Report, from the U.S. Department of Energy. GFO FOIA FY 14 Annual Report (312.51 KB) More Documents & Publications EA-1245: Finding of No Significant Impact EA-1875: Final Environmental Assessment EA-1761: Final Environmental Assessment

  4. Press Pass - Press Releases

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    can obtain temporary visitors' passes. The laboratory will also be closed to pedestrian and bicycle traffic. Fermilab, traditionally open to visitors, closed its gates in...

  5. First Pass | Jefferson Lab

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    First Pass First Pass February 25, 2014 The 12 GeV Upgrade Project at Jefferson Lab has many facets, and it is designed in such a way that some parts are completed and working while others are still in preparation. Recently, we have achieved a notable milestone. The accelerator commissioning was able to demonstrate 2.2 GeV of acceleration in a single pass around the upgraded accelerator. We have seen the completion of the bulk of civil construction work with the Central Helium Liquefier (CHL)

  6. Golden, Colorado: Energy Resources | Open Energy Information

    Open Energy Information (Open El) [EERE & EIA]

    Society Registered Energy Companies in Golden, Colorado Ampulse Ampulse Corporation Blue Sun Biodiesel LLC Colorado Fuel Cell Center CFCC Energistic Systems Energy Solutions...

  7. Golden Opportunity: Compromise Agreement (2013-SE-1418)

    Energy.gov [DOE]

    DOE and Golden Opportunity, Inc. entered into a Compromise Agreement to resolve a case involving the distribution in commerce of noncompliant freezers.

  8. Golden Valley Electric Association - Residential Energy Efficiency...

    Energy.gov (indexed) [DOE]

    30 Timer Controlling Exterior Vehicle Plug-In Outlet: 20 Switch Controlling Exterior Vehicle Plug-In Outlet: 10 Summary Golden Valley Electric Association's (GVEA) Builder...

  9. Golden, Colorado: Energy Resources | Open Energy Information

    Open Energy Information (Open El) [EERE & EIA]

    in Golden, Colorado Ampulse Ampulse Corporation Blue Sun Biodiesel LLC Colorado Fuel Cell Center CFCC Energistic Systems Energy Solutions Partners, LLC Industrial Solar...

  10. Categorical Exclusion Determinations: Golden Field Office | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Program Date: 03252015 Location(s): Nationwide Office(s): Golden Field Office March 24, 2015 CX-100203 Categorical Exclusion Determination Solar Hot Water Project in Greenburgh,...

  11. Golden Turbines LLC | Open Energy Information

    Open Energy Information (Open El) [EERE & EIA]

    LLC Jump to: navigation, search Name: Golden Turbines LLC Address: 280 Meadow Ash Dr Lewis Center Zip: 43035 Region: United States Sector: Marine and Hydrokinetic Year Founded:...

  12. False Pass Wind Resource Report

    Energy Savers

    False Pass Wind Resource Report False Pass meteorological tower, view to the east, D. ... Eagle River, Alaska D r a f t 1 False Pass Wind Resource Report P a g e | 2 Summary The ...

  13. Golden Opportunity: Order (2014-CE-20003)

    Energy.gov [DOE]

    DOE ordered Golden Opportunity, Inc. to pay a $8,000 civil penalty after finding Golden Opportunity had failed to certify that certain models of room air conditioners, central air conditioners/heat pumps, and residential clothes washers comply with the applicable energy conservation standards.

  14. Golden Spread Panhandle Wind Ranch | Open Energy Information

    Open Energy Information (Open El) [EERE & EIA]

    Wind Facility Status In Service Owner Golden Spread Electric Cooperative Developer Cielo Energy Purchaser Golden Spread Electric Cooperative Location Wildarado TX Coordinates...

  15. Golden Reading Room: Office of Acquisition Documents, Better...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Golden Reading Room: Office of Acquisition Documents, Better Buildings Initiative Support Services Below are electronic versions of Golden Field Office Reading Room documents that ...

  16. Golden Reading Room: Office of Acquisition Documents, Sole of...

    Office of Environmental Management (EM)

    Golden Reading Room: Office of Acquisition Documents, Sole of Limited Source Justifications Below are electronic versions of Golden Field Office Reading Room documents that were ...

  17. Commercialization and Project Management PIA, Golden Field Office |

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Department of Energy Commercialization and Project Management PIA, Golden Field Office Commercialization and Project Management PIA, Golden Field Office Commercialization and Project Management PIA, Golden Field Office Commercialization and Project Management PIA, Golden Field Office (219.69 KB) More Documents & Publications Integrated Safety Management Workshop Registration, PIA, Idaho National Laboratory Occupational Medicine - Assistant PIA, Idaho National Laboratory Manchester

  18. Golden, Illinois: Energy Resources | Open Energy Information

    Open Energy Information (Open El) [EERE & EIA]

    Map This article is a stub. You can help OpenEI by expanding it. Golden is a village in Adams County, Illinois. It falls under Illinois' 18th congressional district.12...

  19. Golden Opportunity: Proposed Penalty (2014-CE-20003)

    Energy.gov [DOE]

    DOE alleged in a Notice of Proposed Civil Penalty that Golden Opportunity, Inc. failed to certify room air conditioners, central air conditioners/heat pumps, and residential clothes washers as compliant with the applicable energy conservation standards.

  20. Golden Cooler: Proposed Penalty (2013-CE-5345)

    Energy.gov [DOE]

    DOE alleged in a Notice of Proposed Civil Penalty that Golden Cooler failed to certify a variety of walk-in cooler or freezer components as compliant with the applicable energy conservation standards.

  1. Categorical Exclusion Determinations: Golden Field Office | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Air Conditioners RIN: 1904-AC82 CX(s) Applied: B5.1 EERE- Buildings Technology Program Date: 06172015 Location(s): Nationwide Office(s): Golden Field Office June 16, 2015...

  2. Categorical Exclusion Determinations: Golden Field Office | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Ultrasonic Bat Deterrent Award Number: DE-EE0007035 CX(s) Applied: B3.3 Wind Program Date: 07242015 Location(s): NY Office(s): Golden Field Office July 21, 2015 CX-100313...

  3. Categorical Exclusion Determinations: Golden Field Office | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Award Number: DE- EE-0007182 CX(s) Applied: A9, A11 Solar Energy Technologies Office Date: 10222015 Location(s): CA Office(s): Golden Field Office October 20, 2015 CX-100391...

  4. Categorical Exclusion Determinations: Golden Field Office | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Number: DE-EE0007137 CX(s) Applied: A9, B3.6, B3.11 Solar Energy Technologies Office Date: 09102015 Location(s): AL Office(s): Golden Field Office September 8, 2015 CX-100362...

  5. Golden Field Office 15013 Denver West Parkway

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Golden Field Office 15013 Denver West Parkway Golden, Colorado 80401 September 14, 2016 SUBJECT: Notice of Scoping and Notification of Public Scoping Meeting for the Project Icebreaker Offshore Wind Project Environmental Assessment, Cleveland, Ohio, (DOE/EA-2045, Department of Army Processing No. 2010-00223) The U. S. Department of Energy (DOE), the U.S. Army Corps of Engineers (USACE), and the U.S. Coast Guard (USCG) are requesting public input on the scope of an Environmental Assessment (EA)

  6. Alternative Fuels Data Center: Golden Eagle Distributors Inc. to Convert

    Alternative Fuels and Advanced Vehicles Data Center

    Entire Fleet to CNG Golden Eagle Distributors Inc. to Convert Entire Fleet to CNG to someone by E-mail Share Alternative Fuels Data Center: Golden Eagle Distributors Inc. to Convert Entire Fleet to CNG on Facebook Tweet about Alternative Fuels Data Center: Golden Eagle Distributors Inc. to Convert Entire Fleet to CNG on Twitter Bookmark Alternative Fuels Data Center: Golden Eagle Distributors Inc. to Convert Entire Fleet to CNG on Google Bookmark Alternative Fuels Data Center: Golden Eagle

  7. Golden Field Office Reading Room | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    About Us » Business Operations » Golden Field Office » Golden Field Office Reading Room Golden Field Office Reading Room The Golden Field Office was designated a Department of Energy (DOE) field office in December 1992 to support the development and commercialization of renewable energy and energy-efficient technologies. As a field office within DOE's Office of Energy Efficiency and Renewable Energy (EERE), Golden's mission is to award grants and manage contracts for clean energy projects,

  8. SEMI-ANNUAL REPORTS FOR GOLDEN PASS PRODUCTS LLC - FE DKT. NO...

    Energy.gov (indexed) [DOE]

    - GULF LNG LIQUEFACTION COMPANY, LLC - FE DKT. NO. 12-47-LNG - ORDER 3104 SEMI-ANNUAL REPORTS FOR SOUTHERN LNG COMPANY - FE DKT. NO. 12-54-LNG - ORDER 3106 Semi-annual Reports for...

  9. Golden Pass, TX Natural Gas Liquefied Natural Gas Imports (price) from

    U.S. Energy Information Administration (EIA) (indexed site)

    Qatar (Dollars per Thousand Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 2000's -- -- -- 2010's 7.90 5.36 -- -- -- --

  10. Golden Pass, TX Natural Gas Liquefied Natural Gas Imports (price) from

    U.S. Energy Information Administration (EIA) (indexed site)

    Qatar (Dollars per Thousand Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2011 5.77 6.74 6.74 4.76 4.78

  11. Alternative Fuels Data Center: Golden Eagle Delivers Beer With...

    Alternative Fuels and Advanced Vehicles Data Center

    Golden Eagle Delivers Beer With Natural Gas Trucks to someone by E-mail Share Alternative Fuels Data Center: Golden Eagle Delivers Beer With Natural Gas Trucks on Facebook Tweet ...

  12. Categorical Exclusion Determinations: Golden Field Office | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Energy Categorical Exclusion Determinations: Golden Field Office Categorical Exclusion Determinations: Golden Field Office Categorical Exclusion Determinations issued by Golden Field Office. DOCUMENTS AVAILABLE FOR DOWNLOAD November 10, 2016 CX-100767 Categorical Exclusion Determination FTLB Architectural Maintenance Award Number: DE-AC36-08GO28308 CX(s) Applied: DOE/EA-1968 (NREL STM) National Renewable Energy Lab Date: 11/3/2016 Location(s): CO Office(s): Golden Field Office November 7,

  13. Office of Acquisition and Financial Assessment PIA, Golden Field Office |

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Department of Energy Acquisition and Financial Assessment PIA, Golden Field Office Office of Acquisition and Financial Assessment PIA, Golden Field Office Office of Acquisition and Financial Assessment PIA, Golden Field Office Office of Acquisition and Financial Assessment PIA, Golden Field Office (245.98 KB) More Documents & Publications Integrated Safety Management Workshop Registration, PIA, Idaho National Laboratory Occupational Medicine - Assistant PIA, Idaho National Laboratory

  14. 2012 Annual Planning Summary for Golden Field Office

    Energy.gov [DOE]

    The ongoing and projected Environmental Assessments and Environmental Impact Statements for 2012 and 2013 within Golden Field Office.

  15. Multiple pass laser amplifier system

    DOE Patents [OSTI]

    Brueckner, Keith A.; Jorna, Siebe; Moncur, N. Kent

    1977-01-01

    A laser amplification method for increasing the energy extraction efficiency from laser amplifiers while reducing the energy flux that passes through a flux limited system which includes apparatus for decomposing a linearly polarized light beam into multiple components, passing the components through an amplifier in delayed time sequence and recombining the amplified components into an in phase linearly polarized beam.

  16. Current Fiscal Year FOIA Requests received by Golden Field Office |

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Department of Energy Current Fiscal Year FOIA Requests received by Golden Field Office Current Fiscal Year FOIA Requests received by Golden Field Office Golden Field Office Status of FOIA Requests Received -- Current Quarter FY'16, from the U.S. Department of Energy. GFO Status of FOIA Requests Received (1.31 MB) More Documents & Publications EA-1245: Finding of No Significant Impact EA-1875: Final Environmental Assessment EA-1761: Final Environmental Assessment

  17. Federal Energy Management Program Golden Field Office Contacts | Department

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    of Energy Contact Us » Federal Energy Management Program Golden Field Office Contacts Federal Energy Management Program Golden Field Office Contacts The following field contacts at the U.S. Department of Energy's Golden Field Office support the Federal Energy Management Program (FEMP). FEMP staff contact information is also available. Wayne Latham Energy Savings Performance Contract (ESPC) Contracting Officer 720-356-1507

  18. Golden Reading Room: NEPA Categorical Exclusions | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    NEPA Categorical Exclusions Golden Reading Room: NEPA Categorical Exclusions Categorical Exclusion Determinations issued by Golden Field Office of the Office of Energy Efficiency and Renewable Energy (EERE). DOCUMENTS AVAILABLE FOR DOWNLOAD November 10, 2016 CX-100767 Categorical Exclusion Determination FTLB Architectural Maintenance Award Number: DE-AC36-08GO28308 CX(s) Applied: DOE/EA-1968 (NREL STM) National Renewable Energy Lab Date: 11/3/2016 Location(s): CO Office(s): Golden Field Office

  19. Sabine Pass LNG Terminal | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Sabine Pass LNG Terminal Sabine Pass LNG Terminal Sabine Pass LNG Terminal Long-Term Contract Information and Registrations at U.S. LNG Export Facilities Filing Date Type (1) ...

  20. Golden Hills Solar Power Plant | Open Energy Information

    Open Energy Information (Open El) [EERE & EIA]

    Hills Solar Power Plant Facility Golden Hills Solar Sector Solar Facility Type Photovoltaic Developer PowerWorks Location Alameda County, California Coordinates 37.6016892,...

  1. ORISE: Helping California Prepare for Emergencies through Golden...

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    Golden Guardian ORISE helps California Governor's Office of Emergency Services plan series ... and more than 37,000,000 people, California is at risk for earthquakes, floods, ...

  2. Golden State Holding Group Corporation | Open Energy Information

    Open Energy Information (Open El) [EERE & EIA]

    Holding Group Corporation Jump to: navigation, search Name: Golden State Holding Group Corporation Place: Beijing Municipality, China Product: Beijing-based developer and...

  3. Golden State Renewable Energy Corporation | Open Energy Information

    Open Energy Information (Open El) [EERE & EIA]

    Renewable Energy Corporation Jump to: navigation, search Name: Golden State Renewable Energy Corporation Place: Beijing, Beijing Municipality, China Zip: 100101 Sector: Biomass,...

  4. Golden State Baotou Renewable Energy Ltd | Open Energy Information

    Open Energy Information (Open El) [EERE & EIA]

    Baotou Renewable Energy Ltd Jump to: navigation, search Name: Golden State (Baotou) Renewable Energy Ltd Place: Baotou, Inner Mongolia Autonomous Region, China Sector: Wind energy...

  5. Golden Fuel Systems formerly Greasel Conversions Inc | Open Energy...

    Open Energy Information (Open El) [EERE & EIA]

    Fuel Systems formerly Greasel Conversions Inc Jump to: navigation, search Name: Golden Fuel Systems (formerly Greasel Conversions Inc) Place: Drury, Montana Zip: 65638 Sector:...

  6. 2011 Annual Planning Summary for Golden Field Office (GO)

    Energy.gov [DOE]

    The ongoing and projected Environmental Assessments and Environmental Impact Statements for 2011 and 2012 within the Golden Field Office (GO) (See Energy Efficiency APS).

  7. Golden Valley Electric Association- Sustainable Natural Alternative Power (SNAP) Program

    Office of Energy Efficiency and Renewable Energy (EERE)

    Golden Valley Electric Association's (GVEA) SNAP program encourages members to install renewable energy generators and connect them to the utility's electrical distribution system by offering an...

  8. Golden's Bridge, New York: Energy Resources | Open Energy Information

    Open Energy Information (Open El) [EERE & EIA]

    Golden's Bridge, New York: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 41.290749, -73.67395 Show Map Loading map... "minzoom":false,"mappin...

  9. Golden Beach, Florida: Energy Resources | Open Energy Information

    Open Energy Information (Open El) [EERE & EIA]

    it. Golden Beach is a town in Miami-Dade County, Florida. It falls under Florida's 20th congressional district.12 References US Census Bureau Incorporated place and...

  10. Energy Department Authorizes Sabine Pass Liquefaction's Expansion...

    Energy Savers

    Sabine Pass Liquefaction's Expansion Project to Export Liquefied Natural Gas Energy Department Authorizes Sabine Pass Liquefaction's Expansion Project to Export Liquefied Natural ...

  11. Previous Fiscal Year FOIA Requests received by Golden Field Office

    Energy.gov [DOE]

    Golden Field Office Status of FOIA Requests Received – Previous Fiscal Year, from the U.S. Department of Energy This document provides a listing of all FOIA requests received by the Golden Field Office in the past fiscal year, including a description of the FOIA request and the resolution of the FOIA request.

  12. Golden Reading Room: Office of Acquisition Documents, Small Purchases |

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Department of Energy Small Purchases Golden Reading Room: Office of Acquisition Documents, Small Purchases Below are electronic versions of Golden Field Office Reading Room documents that were created after November 1, 1996, per the requirements of the Electronic Freedom of Information Act Amendment of 1996. Most documents are available in Adobe Acrobat Portable Document Format (PDF). Small Purchases

  13. Golden Eagle Territories and Ecology at Site 300

    SciTech Connect (OSTI)

    Fratanduono, M.

    2015-09-29

    Garcia and Associates (GANDA) was contracted by the Lawrence Livermore National Laboratory (LLNL) to collect information on golden eagle (Aquila chrysaetos) use of Site 300. During 2014, we conducted surveys at Site 300 and for an area including a 10-mile radius of Site 300. Those surveys documented 42 golden eagle territories including two territories that overlapped with Site 300. These were named ‘Tesla’ and ‘Linac Road’. In 2015, we conducted surveys to refine the territory boundaries of golden eagle territories that overlapped with Site 300 and to document eagle activity at Site 300.

  14. Golden Reading Room: FOIA Requester Service Centers and Public Liaisons |

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Department of Energy FOIA Requester Service Centers and Public Liaisons Golden Reading Room: FOIA Requester Service Centers and Public Liaisons U.S. Department of Energy http://energy.gov/management/foia-contacts

  15. Golden Valley Electric Association- Commercial Lighting Retrofit Rebate Program

    Energy.gov [DOE]

    Business $ense is a Golden Valley Electric Association (GVEA) program designed to increase the efficiency with which energy is used on GVEA's system. It provides rebates of up to $20,000 to...

  16. Golden Reading Room: NREL Environmental and NEPA Documents | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Energy NREL Environmental and NEPA Documents Golden Reading Room: NREL Environmental and NEPA Documents Below are electronic versions of Golden Field Office Reading Room documents that were created after November 1, 1996, per the requirements of the Electronic Freedom of Information Act Amendment of 1996. Most documents are available in Adobe Acrobat Portable Document Format (PDF). NREL Annual Environmental Performance Reports (Annual Site Environmental Reports) Every year the National

  17. Golden Reading Room: Other NREL Documents | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Other NREL Documents Golden Reading Room: Other NREL Documents Below are electronic versions of Golden Field Office Reading Room documents that were created after November 1, 1996, per the requirements of the Electronic Freedom of Information Act Amendment of 1996. Most documents are available in Adobe Acrobat Portable Document Format (PDF). National Renewable Energy Laboratory 10 Year Site Plan FY 2007 - FY 2018 Director's Discretionary Research and Development Program, Annual Report FY 2007

  18. Golden Reading Room: FINAL Environmental Impact Statements | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Energy FINAL Environmental Impact Statements Golden Reading Room: FINAL Environmental Impact Statements Below are electronic versions of Golden Field Office Reading Room documents that were created after November 1, 1996, per the requirements of the Electronic Freedom of Information Act Amendment of 1996. Most documents are available in Adobe Acrobat Portable Document Format (PDF). Final Environmental Impact Statement for the Proposed Abengoa Biorefinery Project, Hugoton, Stevens County,

  19. Golden Reading Room: FOIA Frequently Requested Documents | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Energy Frequently Requested Documents Golden Reading Room: FOIA Frequently Requested Documents Below are electronic versions of Golden Field Office Reading Room documents that were created after November 1, 1996, per the requirements of the Electronic Freedom of Information Act Amendment of 1996. Most documents are available in Adobe Acrobat Portable Document Format (PDF). DE-EE0002884 Sapphire Energy GO-12-043 Redacted Sapphire FOIA DE-EE0002877 Recovery Act Definitized Subcontract No.

  20. Golden Reading Room: FOIA Proactive Disclosures and Contracts | Department

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    of Energy Proactive Disclosures and Contracts Golden Reading Room: FOIA Proactive Disclosures and Contracts Below are electronic versions of Golden Field Office Reading Room documents that were created after November 1, 1996, per the requirements of the Electronic Freedom of Information Act Amendment of 1996. Most documents are available in Adobe Acrobat Portable Document Format (PDF). 2013 Solar Decathlon Information Click on this link for updates: Solar Decathlon Information. Alliance for

  1. Golden Reading Room: Office of Acquisition Documents, Better Buildings

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Initiative Support Services | Department of Energy Better Buildings Initiative Support Services Golden Reading Room: Office of Acquisition Documents, Better Buildings Initiative Support Services Below are electronic versions of Golden Field Office Reading Room documents that were created after November 1, 1996, per the requirements of the Electronic Freedom of Information Act Amendment of 1996. Most documents are available in Adobe Acrobat Portable Document Format (PDF). DE-SOL-0005538

  2. Golden Reading Room: Office of Acquisition Documents, Sole of Limited

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Source Justifications | Department of Energy Sole of Limited Source Justifications Golden Reading Room: Office of Acquisition Documents, Sole of Limited Source Justifications Below are electronic versions of Golden Field Office Reading Room documents that were created after November 1, 1996, per the requirements of the Electronic Freedom of Information Act Amendment of 1996. Most documents are available in Adobe Acrobat Portable Document Format (PDF). Sole of Limited Source Justificati

  3. Golden Reading Room: Other NEPA Documents | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Other NEPA Documents Golden Reading Room: Other NEPA Documents Below are electronic versions of Golden Field Office Reading Room documents that were created after November 1, 1996, per the requirements of the Electronic Freedom of Information Act Amendment of 1996. Most documents are available in Adobe Acrobat Portable Document Format (PDF). Floodplain Assessment for Installation of a Renewable Energy Anaerobic Digester Facility at the University of California, Davis in Yolo County, California

  4. Patterson Pass Wind Farm | Open Energy Information

    Open Energy Information (Open El) [EERE & EIA]

    Wind Companies Developer International Wind Companies Energy Purchaser Pacific Gas & Electric Co Location Altamont Pass CA Coordinates 37.7347, -121.652 Show Map...

  5. Photoacoustic Soot Spectrometer (PASS) Instrument Handbook

    SciTech Connect (OSTI)

    Dubey, M; Springston, S; Koontz, A; Aiken, A

    2013-01-17

    The photoacoustic soot spectrometer (PASS) measures light absorption by aerosol particles. As the particles pass through a laser beam, the absorbed energy heats the particles and in turn the surrounding air, which sets off a pressure wave that can be detected by a microphone. The PASS instruments deployed by ARM can also simultaneously measure the scattered laser light at three wavelengths and therefore provide a direct measure of the single-scattering albedo. The Operator Manual for the PASS-3100 is included here with the permission of Droplet Measurement Technologies, the instruments manufacturer.

  6. Photoacoustic Soot Spectrometer (PASS) Instrument Handbook (Technical...

    Office of Scientific and Technical Information (OSTI)

    The PASS instruments deployed by ARM can also simultaneously measure the scattered laser light at three wavelengths and therefore provide a direct measure of the single-scattering ...

  7. Waste Treatment Facility Passes Federal Inspection, Completes...

    Office of Environmental Management (EM)

    Completes Final Milestone, Begins Startup Waste Treatment Facility Passes Federal ... The Idaho site today initiated the controlled, phased startup of a new waste treatment ...

  8. Multifrequency, single pass free electron laser

    DOE Patents [OSTI]

    Szoke, Abraham; Prosnitz, Donald

    1985-01-01

    A method for simultaneous amplification of laser beams with a sequence of frequencies in a single pass, using a relativistic beam of electrons grouped in a sequence of energies corresponding to the sequence of laser beam frequencies. The method allows electrons to pass from one potential well or "bucket" to another adjacent bucket, thus increasing efficiency of trapping and energy conversion.

  9. A golden anniversary for space-based treaty verification

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    A golden anniversary for space-based treaty verification A golden anniversary for space-based treaty verification Fifty years ago this month, LANL sensor technology lifted off into space to help verify that world Superpowers were abiding by the newly signed Limited Test Ban Treaty. October 22, 2013 Los Alamos National Laboratory researcher Richard Belian performs a final check of the Vela V-B satellite prior to its launch in April 1970. Vela V-B was the last of the Vela twin satellites launched

  10. Golden Reading Room: Freedom of Information Act (FOIA) | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Energy Freedom of Information Act (FOIA) Golden Reading Room: Freedom of Information Act (FOIA) The Golden FOIA Office within the Office of Energy Efficiency and Renewable Energy (EERE) exists to execute the legal requirements of the Freedom of Information Act (5 U.S.C. § 552(a)(3)(A) (2006), amended by OPEN Government Act of 2007, Pub. L. No. 110175, 121 Stat. 2524). Enacted on July 4, 1966, and taking effect on one year later, the Freedom of Information Act provides that any person has a

  11. Technical Feasibility Assessment of LED Roadway Lighting on the Golden Gate Bridge

    SciTech Connect (OSTI)

    Tuenge, J. R.

    2012-09-01

    GATEWAY program report on the technical feasibility of LED roadway lighting on the Golden Gate Bridge in San Francisco, CA.

  12. WA_1993_033_GOLDEN_PHOTON_INC_Waiver_of_Domestic_and_Foreign.pdf |

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Department of Energy 3_033_GOLDEN_PHOTON_INC_Waiver_of_Domestic_and_Foreign.pdf WA_1993_033_GOLDEN_PHOTON_INC_Waiver_of_Domestic_and_Foreign.pdf (1.15 MB) More Documents & Publications WA_1995_030_GOLDEN_PHOTON_INC_Waiver_of_Domestic_and_Foreign.pdf WA_1994_003_GOLDEN_PHOTOCON_INC_Waiver_of_Domestic_and_Forei

  13. WA_1995_030_GOLDEN_PHOTON_INC_Waiver_of_Domestic_and_Foreign.pdf |

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Department of Energy 5_030_GOLDEN_PHOTON_INC_Waiver_of_Domestic_and_Foreign.pdf WA_1995_030_GOLDEN_PHOTON_INC_Waiver_of_Domestic_and_Foreign.pdf (8.82 MB) More Documents & Publications WA_1994_003_GOLDEN_PHOTOCON_INC_Waiver_of_Domestic_and_Forei.pdf WA_1993_033_GOLDEN_PHOTON_INC_Waiver_of_Domestic_and_Foreign

  14. Order 3669: Sabine Pass Liquefaction, LLC

    Office of Energy Efficiency and Renewable Energy (EERE)

    FINAL OPINION AND ORDER GRANTING LONG-TERM, MULTI-CONTRACT AUTHORIZATION TO EXPORT LIQUEFIED NATURAL GAS BY VESSEL FROM THE SABINE PASS LNG TERMINAL LOCATED IN THE CAMERON PARISH, LOUISIANA, TO NON...

  15. COLORADO GOLDEN FIELD OFFICE POC Karen Downs Telephone

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    TRANSPORTATION & WAREHOUSING COLORADO GOLDEN FIELD OFFICE POC Karen Downs Telephone (720) 356-1269 Email karen.downs@go.doe.gov Other Support Activities for Air Transportation 488190 Freight Transportation Arrangement 488510 General Warehousing and Storage 493110 NATIONAL RENEWABLE ENERGY LAB POC Nancy Gardner Telephone (303) 384-7335 Email nancy.gardner@nrel.gov Specialized Freight (except Used Goods) Trucking, Local 484220 ROCKY FLATS POC Telephone Email Specialized Freight (except Used

  16. PUBLIC ADMINISTRATION COLORADO GOLDEN FIELD OFFICE POC Karen Downs

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    PUBLIC ADMINISTRATION COLORADO GOLDEN FIELD OFFICE POC Karen Downs Telephone (720) 356-1269 Email karen.downs@go.doe.gov Police Protection 922120 Administration of Education Programs 923110 International Affairs 928120 DIST OF COLUMBIA HEADQUARTERS PROCUREMENT POC Michael Raizen Telephone (202) 287-1512 Email michael.raizen@hq.doe.gov Police Protection 922120 Administration of Education Programs 923110 Administration of Human Resource Programs (except Education, Public Health, and Veterans'

  17. Security Procedures for Golden Laboratories and Administration Offices |

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    NREL Security Procedures for Golden Laboratories and Administration Offices Visitors are required to show government-issued photo identification (for example driver's license, passport, or military ID). Upon arrival to NREL's South Table Mountain site, visitors are to drive up to the East Site Entrance Building window where Security staff will confirm they are on the expected visitor list. Visitors will receive a parking placard and should park in the Research Support Facility (RSF) Visitor

  18. Senate Energy Committee Passes New Geothermal Legislation

    Energy.gov [DOE]

    Senate Energy Committee moved the ball forward for geothermal energy by passing two important geothermal measures, S. 1142 and S. 1149, on December 15. "These two measures will support exploration drilling, expand geothermal research into heating uses, and expedite leasing and development," remarked GEA Executive Director Karl Gawell.

  19. Message passing with parallel queue traversal

    DOE Patents [OSTI]

    Underwood, Keith D.; Brightwell, Ronald B.; Hemmert, K. Scott

    2012-05-01

    In message passing implementations, associative matching structures are used to permit list entries to be searched in parallel fashion, thereby avoiding the delay of linear list traversal. List management capabilities are provided to support list entry turnover semantics and priority ordering semantics.

  20. FINDING OF NO SIGNIFICANT IMPACT FOR SABINE PASS LIQUEFACTION...

    Energy Savers

    EXPANSION PROJECT REGARDING SABINE PASS LIQUEFACTION, LLC, APPLICATIONS SEEKING DEPARTMENT OF ENERGY AUTHORIZATION TO EXPORT LIQUEFIED NATURAL GAS FROM SABINE PASS LNG TERMINAL TO ...

  1. Savine Pass, LA Natural Gas Liquefied Natural Gas Imports from...

    Gasoline and Diesel Fuel Update

    Savine Pass, LA Natural Gas Liquefied Natural Gas Imports from Trinidad and Tobago (Million Cubic Feet) Savine Pass, LA Natural Gas Liquefied Natural Gas Imports from Trinidad and ...

  2. EA-2036: Sabine Pass Liquefaction Project (design optimization...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    36: Sabine Pass Liquefaction Project (design optimization); Cameron Parish, Louisiana EA-2036: Sabine Pass Liquefaction Project (design optimization); Cameron Parish, Louisiana ...

  3. Two former longtime employees pass away | The Ames Laboratory

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    employees pass away Former Ames Laboratory metallurgy program chair John (Jack) Smith of Ames passed away Sept. 26 and long-time facilities plumber Pat Stowell of Boone,...

  4. Technical Feasibility Assessment of LED Roadway Lighting on the Golden Gate

    Office of Scientific and Technical Information (OSTI)

    Bridge (Technical Report) | SciTech Connect Technical Feasibility Assessment of LED Roadway Lighting on the Golden Gate Bridge Citation Details In-Document Search Title: Technical Feasibility Assessment of LED Roadway Lighting on the Golden Gate Bridge Subsequent to preliminary investigations by the Golden Gate Bridge Highway & Transportation District (GGB), in coordination with Pacific Gas & Electric (PG&E), the GATEWAY Demonstration program was asked to evaluate the technical

  5. General Atomics (GA) | Princeton Plasma Physics Lab

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    General Atomics (GA) Subscribe to RSS - General Atomics (GA) General Atomics Image: General Atomics (GA) The Scorpion's Strategy: "Catch and Subdue" Read more about The Scorpion's...

  6. Extracting Effective Higgs Couplings in the Golden Channel

    DOE PAGES-Beta [OSTI]

    Chen, Yi; Vega-Morales, Roberto

    2014-04-08

    Kinematic distributions in Higgs decays to four charged leptons, the so called ‘golden channel, are a powerful probe of the tensor structure of its couplings to neutral electroweak gauge bosons. In this study we construct the first part of a comprehensive analysis framework designed to maximize the information contained in this channel in order to perform direct extraction of the various possible Higgs couplings. We first complete an earlier analytic calculation of the leading order fully differential cross sections for the golden channel signal and background to include the 4e and 4μ final states with interference between identical final states.more » We also examine the relative fractions of the different possible combinations of scalar-tensor couplings by integrating the fully differential cross section over all kinematic variables as well as show various doubly differential spectra for both the signal and background. From these analytic expressions we then construct a ‘generator level’ analysis framework based on the maximum likelihood method. Then, we demonstrate the ability of our framework to perform multi-parameter extractions of all the possible effective couplings of a spin-0 scalar to pairs of neutral electroweak gauge bosons including any correlations. Furthermore, this framework provides a powerful method for study of these couplings and can be readily adapted to include the relevant detector and systematic effects which we demonstrate in an accompanying study to follow.« less

  7. Microsoft Word - Northern Pass Amended Application - FINAL

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    UNITED STATES OF AMERICA BEFORE THE DEPARTMENT OF ENERGY OFFICE OF ELECTRICITY DELIVERY AND ENERGY RELIABILITY NORTHERN PASS TRANSMISSION LLC DOCKET NO. PP-371 AMENDED APPLICATION JULY 1, 2013 i TABLE OF CONTENTS Page No. LIST OF EXHIBITS iii LIST OF ABBREVIATIONS iv INTRODUCTION 1 OVERVIEW OF AMENDMENTS TO APPLICATION 1 SECTION 1 - INFORMATION REGARDING THE APPLICANT 1.1 Legal Name of the Applicant 6 1.2 Legal Names of All Partners 6 1.3 Communications and Correspondence 7 1.4 Foreign Ownership

  8. Sabine Pass, LA Liquefied Natural Gas Imports From Norway (Million...

    Annual Energy Outlook

    Norway (Million Cubic Feet) Sabine Pass, LA Liquefied Natural Gas Imports From Norway ... Referring Pages: U.S. Liquefied Natural Gas Imports by Point of Entry Sabine Pass, LA LNG ...

  9. Two antenna, two pass interferometric synthetic aperture radar

    DOE Patents [OSTI]

    Martinez, Ana; Doerry, Armin W.; Bickel, Douglas L.

    2005-06-28

    A multi-antenna, multi-pass IFSAR mode utilizing data driven alignment of multiple independent passes can combine the scaling accuracy of a two-antenna, one-pass IFSAR mode with the height-noise performance of a one-antenna, two-pass IFSAR mode. A two-antenna, two-pass IFSAR mode can accurately estimate the larger antenna baseline from the data itself and reduce height-noise, allowing for more accurate information about target ground position locations and heights. The two-antenna, two-pass IFSAR mode can use coarser IFSAR data to estimate the larger antenna baseline. Multi-pass IFSAR can be extended to more than two (2) passes, thereby allowing true three-dimensional radar imaging from stand-off aircraft and satellite platforms.

  10. Venture Global Calcasieu Pass, LLC - (Formerly Venture Global...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Venture Global Calcasieu Pass, LLC - (Formerly Venture Global LNG, LLC) - 14-88-LNG Venture Global Calcasieu Pass, LLC - (Formerly Venture Global LNG, LLC) - 14-88-LNG The Office ...

  11. Quantum Monte Carlo by message passing

    SciTech Connect (OSTI)

    Bonca, J.; Gubernatis, J.E.

    1993-01-01

    We summarize results of quantum Monte Carlo simulations of the degenerate single-impurity Anderson model using the impurity algorithm of Hirsch and Fye. Using methods of Bayesian statistical inference, coupled with the principle of maximum entropy, we extracted the single-particle spectral density from the imaginary-time Green's function. The variations of resulting spectral densities with model parameters agree qualitatively with the spectral densities predicted by NCA calculations. All the simulations were performed on a cluster of 16 IBM R6000/560 workstations under the control of the message-passing software PVM. We described the trivial parallelization of our quantum Monte Carlo code both for the cluster and the CM-5 computer. Other issues for effective parallelization of the impurity algorithm are also discussed.

  12. Quantum Monte Carlo by message passing

    SciTech Connect (OSTI)

    Bonca, J.; Gubernatis, J.E.

    1993-05-01

    We summarize results of quantum Monte Carlo simulations of the degenerate single-impurity Anderson model using the impurity algorithm of Hirsch and Fye. Using methods of Bayesian statistical inference, coupled with the principle of maximum entropy, we extracted the single-particle spectral density from the imaginary-time Green`s function. The variations of resulting spectral densities with model parameters agree qualitatively with the spectral densities predicted by NCA calculations. All the simulations were performed on a cluster of 16 IBM R6000/560 workstations under the control of the message-passing software PVM. We described the trivial parallelization of our quantum Monte Carlo code both for the cluster and the CM-5 computer. Other issues for effective parallelization of the impurity algorithm are also discussed.

  13. Energy Systems Integration Facility (ESIF): Golden, CO - Energy Integration

    SciTech Connect (OSTI)

    Sheppy, Michael; VanGeet, Otto; Pless, Shanti; Gaul, Chris

    2015-03-01

    At NREL's Energy Systems Integration Facility (ESIF) in Golden, Colo., scientists and engineers work to overcome challenges related to how the nation generates, delivers and uses energy by modernizing the interplay between energy sources, infrastructure, and data. Test facilities include a megawatt-scale ac electric grid, photovoltaic simulators and a load bank. Additionally, a high performance computing data center (HPCDC) is dedicated to advancing renewable energy and energy efficient technologies. A key design strategy is to use waste heat from the HPCDC to heat parts of the building. The ESIF boasts an annual EUI of 168.3 kBtu/ft2. This article describes the building's procurement, design and first year of performance.

  14. Design of the polarization multi-pass Thomson scattering system

    SciTech Connect (OSTI)

    Yasuhara, R.; Yamada, I.; Kawahata, K.; Funaba, H. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki, Gifu 509-5292 (Japan); Yoshikawa, M.; Morimoto, M.; Shima, Y.; Kohagura, J.; Sakamoto, M.; Nakashima, Y.; Imai, T. [Plasma Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 (Japan); Minami, T. [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)

    2012-10-15

    A novel configuration of the multi-pass Thomson scattering (TS) system is proposed to improve the time resolution and accuracy of electron temperature measurements by use of a polarization control technique. This configuration can realize a perfect coaxial multi-passing at each pass, and the number of round trips is not limited by the optical configuration. To confirm the feasibility of the new method, we installed this system in the GAMMA 10 plasma system. As a result, the integrated scattering signal of the double-pass configuration is about two times larger than that of the single-pass configuration. These results are in good agreement with the design.

  15. STATEMENT OF CONSIDERATIONS REQUEST BY GOLDEN PHOTON INC. FOR AN ADVANCE WAIVER OF

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    CONSIDERATIONS REQUEST BY GOLDEN PHOTON INC. FOR AN ADVANCE WAIVER OF DOMESTIC AND FOREIGN RIGHTS UNDER NREL SUBCONTRACT NUMBER: ZAI-4-11294-3 UNDER DOE CONTRACT NO: DE-ACO2- 83CH10093; W(A)-94-003; CH-0827 Golden Photon Inc. (GPI), a wholly owned subsidiary of Golden Technologies Company, Inc., has petitioned for an Advance Waiver of Patent Rights under NREL Subcontract No. ZAI-4-11294-3, entitled "Photovoltaic Manufacturing Technology, Phase 2B - Process Specific Issues." GPI

  16. Tracking particles by passing messages between images

    SciTech Connect (OSTI)

    Chertkov, Michael; Kroc, Lukas; Zdeborova, Lenka; Krakala, Florent; Vergassola, M

    2009-01-01

    Methods to extract information from the tracking of mobile objects/particles have broad interest in biological and physical sciences. Techniques based on the simple criterion of proximity in time-consecutive snapshots are useful to identify the trajectories of the particles. However, they become problematic as the motility and/or the density of the particles increases because of the uncertainties on the trajectories that particles have followed during the acquisition time of the images. Here, we report efficient methods for learning parameters of the dynamics of the particles from their positions in time-consecutive images. Our algorithm belongs to the class of message-passing algorithms, also known in computer science, information theory and statistical physics under the name of Belief Propagation (BP). The algorithm is distributed, thus allowing parallel implementation suitable for computations on multiple machines without significant inter-machine overhead. We test our method on the model example of particle tracking in turbulent flows, which is particularly challenging due to the strong transport that those flows produce. Our numerical experiments show that the BP algorithm compares in quality with exact Markov Chain Monte-Carlo algorithms, yet BP is far superior in speed. We also suggest and analyze a random-distance model that provides theoretical justification for BP accuracy. Methods developed here systematically formulate the problem of particle tracking and provide fast and reliable tools for its extensive range of applications.

  17. Bird Mortaility at the Altamont Pass Wind Resource Area: March 1998--September 2001

    SciTech Connect (OSTI)

    Smallwood, K. S.; Thelander, C. G.

    2005-09-01

    Over the past 15 years, research has shown that wind turbines in the Altamont Pass Wind Resource Area (APWRA) kill many birds, including raptors, which are protected by the Migratory Bird Treaty Act (MBTA), the Bald and Golden Eagle Protection Act, and/or state and federal Endangered Species Acts. Early research in the APWRA on avian mortality mainly attempted to identify the extent of the problem. In 1998, however, the National Renewable Energy Laboratory (NREL) initiated research to address the causal relationships between wind turbines and bird mortality. NREL funded a project by BioResource Consultants to perform this research directed at identifying and addressing the causes of mortality of various bird species from wind turbines in the APWRA.With 580 megawatts (MW) of installed wind turbine generating capacity in the APWRA, wind turbines there provide up to 1 billion kilowatt-hours (kWh) of emissions-free electricity annually. By identifying and implementing new methods and technologies to reduce or resolve bird mortality in the APWRA, power producers may be able to increase wind turbine electricity production at the site and apply similar mortality-reduction methods at other sites around the state and country.

  18. Agenda for the PV Module Reliability Workshop, February 26- 27 2013, Golden, Colorado

    Office of Energy Efficiency and Renewable Energy (EERE)

    This document is the agenda and poster session information for the NREL 2013 Photovoltaic Module Reliability Workshop, held on February 26-27, 2013 at the National Renewable Energy Laboratory in Golden, CO.

  19. Golden Sun Fujian Solar Technic Co Ltd GS Solar | Open Energy...

    Open Energy Information (Open El) [EERE & EIA]

    Sun Fujian Solar Technic Co Ltd GS Solar Jump to: navigation, search Name: Golden Sun (Fujian) Solar Technic Co Ltd (GS-Solar) Place: Quanzhou, Fujian Province, China Zip: 362000...

  20. Kick Off Meeting for New Fuel Cell Projects - Golden Field Office |

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Department of Energy Kick Off Meeting for New Fuel Cell Projects - Golden Field Office Kick Off Meeting for New Fuel Cell Projects - Golden Field Office These slides were presented at the 2010 New Fuel Cell Projects Meeting on September 28, 2010. 2_reporting_kleen.pdf (684.75 KB) More Documents & Publications Kick-Off Meeting for New Fuel Cell Projects Kickoff Meeting for New Fuel Cell Projects DOE Fuel Cell Subprogram (Presentation)

  1. Investigation of the GaN-on-GaAs interface for vertical power device applications

    SciTech Connect (OSTI)

    Mreke, Janina Uren, Michael J.; Kuball, Martin; Novikov, Sergei V.; Foxon, C. Thomas; Hosseini Vajargah, Shahrzad; Wallis, David J.; Humphreys, Colin J.; Haigh, Sarah J.; Al-Khalidi, Abdullah; Wasige, Edward; Thayne, Iain

    2014-07-07

    GaN layers were grown onto (111) GaAs by molecular beam epitaxy. Minimal band offset between the conduction bands for GaN and GaAs materials has been suggested in the literature raising the possibility of using GaN-on-GaAs for vertical power device applications. I-V and C-V measurements of the GaN/GaAs heterostructures however yielded a rectifying junction, even when both sides of the junction were heavily doped with an n-type dopant. Transmission electron microscopy analysis further confirmed the challenge in creating a GaN/GaAs Ohmic interface by showing a large density of dislocations in the GaN layer and suggesting roughening of the GaN/GaAs interface due to etching of the GaAs by the nitrogen plasma, diffusion of nitrogen or melting of Ga into the GaAs substrate.

  2. Quaternary InGaAsSb Thermophotovoltaic Diode Technology

    SciTech Connect (OSTI)

    M Dashiell; J Beausang; H Ehsani; G Nichols; D DePoy; L Danielson; P Talamo; K Rahner; E Brown; S Burger; P Fourspring; W Topper; P Baldasaro; C Wang; R Huang; M Connors; G Turner; Z Shellenbarger; G Taylor; Jizhong Li; R Martinelli; D Donetski; S Anikeev; G Belenky; S Luryl

    2005-01-26

    Thermophotovoltaic (TPV) diodes fabricated from InGaAsSb alloys lattice-matched to GaSb substrates are grown by Metal Organic Vapor Phase Epitaxy (MOVPE). 0.53eV InGaAsSb TPV diodes utilizing front-surface spectral control filters have been tested in a vacuum cavity and a TPV thermal-to-electric conversion efficiency ({eta}{sub TPV}) and a power density (PD) of {eta}{sub TPV} = 19% and PD=0.58 W/cm{sup 2} were measured for T{sub radiator} = 950 C and T{sub diode} = 27 C. Recombination coefficients deduced from minority carrier measurements and the theory reviewed in this article predict a practical limit to the maximum achievable conversion efficiency and power density for 0.53eV InGaAsSb TPV. The limits for the above operating temperatures are projected to be {eta}{sub TPV} = 26% and PD = 0.75 W/cm{sup 2}. These limits are extended to {eta}{sub TPV} = 30% and PD = 0.85W/cm{sup 2} if the diode active region is bounded by a reflective back surface to enable photon recycling and a two-pass optical path length. The internal quantum efficiency of the InGaAsSb TPV diode is close to the theoretically predicted limits, with the exception of short wavelength absorption in GaSb contact layers. Experiments show that the open circuit voltage of the 0.53eV InGaAsSb TPV diodes is not strongly dependent on the device architectures studied in this work where both N/P and P/N double heterostructure diodes have been grown with various acceptor and donor doping levels, having GaSb and AlGaAsSb confinement, and also partial back surface reflectors. Lattice matched InGaAsSb TPV diodes were fabricated with bandgaps ranging from 0.6 to 0.5eV without significant degradation of the open circuit voltage factor, quantum efficiency, or fill factor as the composition approached the miscibility gap. The key diode performance parameter which is limiting efficiency and power density below the theoretical limits in InGaAsSb TPV devices is the open circuit voltage. The open circuit voltages of

  3. National Wind Technology Center sitewide, Golden, CO: Environmental assessment

    SciTech Connect (OSTI)

    1996-11-01

    The National Renewable Energy Laboratory (NREL), the nation`s primary solar and renewable energy research laboratory, proposes to expand its wind technology research and development program activities at its National Wind Technology Center (NWTC) near Golden, Colorado. NWTC is an existing wind energy research facility operated by NREL for the US Department of Energy (DOE). Proposed activities include the construction and reuse of buildings and facilities, installation of up to 20 wind turbine test sites, improvements in infrastructure, and subsequent research activities, technology testing, and site operations. In addition to wind turbine test activities, NWTC may be used to support other NREL program activities and small-scale demonstration projects. This document assesses potential consequences to resources within the physical, biological, and human environment, including potential impacts to: air quality, geology and soils, water resources, biological resources, cultural and historic resources, socioeconomic resources, land use, visual resources, noise environment, hazardous materials and waste management, and health and safety conditions. Comment letters were received from several agencies in response to the scoping and predecisional draft reviews. The comments have been incorporated as appropriate into the document with full text of the letters contained in the Appendices. Additionally, information from the Rocky Flats Environmental Technology Site on going sitewide assessment of potential environmental impacts has been reviewed and discussed by representatives of both parties and incorporated into the document as appropriate.

  4. Implications of the Higgs discovery in the MSSM golden region.

    SciTech Connect (OSTI)

    Low, I.; Shalgar, S.; High Energy Physics; Northwestern Univ.

    2009-01-01

    If the lightest CP-even Higgs boson in the MSSM is discovered at the LHC, two measurements could be made simultaneously: the Higgs mass m{sub h} and the event rate B{sigma}(gg {yields} h {yields} {gamma}{gamma}). We study to what extent the combination of these two measurements would allow us to extract parameters in the stop mass matrix, including the off-diagonal mixing term, with a focus on the MSSM golden region where the stops are light and the mixing is large. Even though both the production cross-section and the decay amplitude are not sensitive to supersymmetric parameters outside of the stop sector, the branching ratio depends on the total decay width, which is dominated by the Higgs decay to b quarks and sensitive to both the pseudo-scalar mass m{sub A} and the supersymmetric Higgs mass {mu}. In the end we find m{sub A} is an important input in extracting the stop mass parameters, while a fair estimate of the off-diagonal mixing term could be obtained without prior knowledge of {mu}.

  5. EIS-0510: Calcasieu Pass Project, Cameron Parish, Louisiana ...

    Energy Savers

    environmental impacts of the Calcasieu Pass Project, a proposed liquefied natural gas (LNG) export terminal in Cameron Parish, Louisiana. DOE is a cooperating agency in preparing...

  6. MHK Projects/Deception Pass Tidal Energy Hydroelectric Project...

    Open Energy Information (Open El) [EERE & EIA]

    Deception Pass Tidal Energy Hydroelectric Project < MHK Projects Jump to: navigation, search << Return to the MHK database homepage Loading map... "minzoom":false,"mappingservice"...

  7. EA-1845: Sabine Pass Liquefaction Project, Cameron County, LA

    Energy.gov [DOE]

    DOE participated as a cooperating agency with the Federal Energy Regulatory Commission (FERC) in preparing an EA for the Sabine Pass Liquefaction Project to analyze the potential environmental impacts associated with applications submitted by Sabine Pass Liquefaction, LLC, and Sabine Pass LNG, L.P., to FERC and to DOE’s Office of Fossil Energy (FE) seeking authorization to site, construct, and operate liquefaction and export facilities at the existing Sabine Pass LNG Terminal in Cameron Parish, Louisiana. DOE adopted FERC’s EA and issued a finding of no significant impact on August 7, 2012.

  8. Issuance, Control and Use of Badges, Passes, and Credentials

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

    1988-12-19

    The change provides clarification of badges and passes used for escorted visitors into DOE facilities. Chg 1, dated 12-19-88

  9. Issuance, Control and Use of Badges, Passes and Credentials

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

    1988-02-03

    The order establishes and prescribes DOE policies and procedures for the issuance. control. and use of badges. passes, and credentials. Cancels DOE 5631.3.

  10. Feasibility of Tital and Ocean Current Energy in False Pass,...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    - Alaska Feasibility of Tidal and Ocean Current Energy in False Pass, Aleutian Islands, ... to seven sites to assess hazards to successful ADCP deployment and retrieval. ...

  11. Consider Installing Turbulators on Two- and Three-Pass Firetube...

    Energy.gov (indexed) [DOE]

    steam systems. STEAM TIP SHEET 25 Consider Installing Turbulators on Two- and Three-Pass Firetube Boilers (January 2012) (373.54 KB) More Documents & Publications Clean Boiler ...

  12. EIS-0463: Northern Pass Transmission Line Project, New Hampshire...

    Energy.gov (indexed) [DOE]

    permit to Northern Pass Transmission, LLC, to construct, operate, maintain, and connect a new electric transmission line across the U.S.-Canada border in northern New Hampshire. ...

  13. GA SNC Solar | Open Energy Information

    Open Energy Information (Open El) [EERE & EIA]

    GA-SNC Solar Place: Nevada Sector: Solar Product: Nevada-based PV project developer and joint venture of GA-Solar North America and Sierra Nevada Corp. References: GA-SNC...

  14. Performance of a double pass solar air collector

    SciTech Connect (OSTI)

    Ramani, B.M.; Gupta, Akhilesh; Kumar, Ravi

    2010-11-15

    Double pass counter flow solar air collector with porous material in the second air passage is one of the important and attractive design improvement that has been proposed to improve the thermal performance. This paper presents theoretical and experimental analysis of double pass solar air collector with and without porous material. A mathematical model has been developed based on volumetric heat transfer coefficient. Effects of various parameters on the thermal performance and pressure drop characteristics have been discussed. Comparison of results reveals that the thermal efficiency of double pass solar air collector with porous absorbing material is 20-25% and 30-35% higher than that of double pass solar air collector without porous absorbing material and single pass collector respectively. (author)

  15. The Golden-Thompson inequality: Historical aspects and random matrix applications

    SciTech Connect (OSTI)

    Forrester, Peter J. Thompson, Colin J.

    2014-02-15

    The Golden-Thompson inequality, Tr?(e{sup A+B}) ? Tr?(e{sup A}e{sup B}) for A, B Hermitian matrices, appeared in independent works by Golden and Thompson published in 1965. Both of these were motivated by considerations in statistical mechanics. In recent years the Golden-Thompson inequality has found applications to random matrix theory. In this article, we detail some historical aspects relating to Thompson's work, giving in particular a hitherto unpublished proof due to Dyson, and correspondence with Plya. We show too how the 2 2 case relates to hyperbolic geometry, and how the original inequality holds true with the trace operation replaced by any unitarily invariant norm. In relation to the random matrix applications, we review its use in the derivation of concentration type lemmas for sums of random matrices due to Ahlswede-Winter, and Oliveira, generalizing various classical results.

  16. Sabine Pass, LA Exports to Spain Liquefied Natural Gas (Million...

    U.S. Energy Information Administration (EIA) (indexed site)

    Spain Liquefied Natural Gas (Million Cubic Feet) Sabine Pass, LA Exports to Spain Liquefied Natural Gas (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ...

  17. Sabine Pass, LA Liquefied Natural Gas Imports From Yemen (Million...

    U.S. Energy Information Administration (EIA) (indexed site)

    Yemen (Million Cubic Feet) Sabine Pass, LA Liquefied Natural Gas Imports From Yemen (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2011 3,115 3,122 3,106 ...

  18. Sabine Pass, LA Liquefied Natural Gas Exports to China (Million...

    U.S. Energy Information Administration (EIA) (indexed site)

    China (Million Cubic Feet) Sabine Pass, LA Liquefied Natural Gas Exports to China (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2011 3,354 2,848 - No ...

  19. Order 3669: Sabine Pass Liquefaction, LLC | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    FROM THE SABINE PASS LNG TERMINAL LOCATED IN THE CAMERON PARISH, LOUISIANA, TO NON-FREE TRADE AGREEMENT NATIONS Based on a review of the complete record and for the reasons set...

  20. Sabine Pass Liquefaction, LLC- Dkt. No 15-63-LNG

    Energy.gov [DOE]

    The Office of Fossil Energy gives notice of receipt of an Application filed on April 20, 2015, by Sabine Pass Liquefaction, LLC (SPL), seeking long-term multi-contract authorization to export...

  1. FOR OFFICIAL USE ONLY KIRTLAND AFB PASS REQUEST SPONSOR'S INFORMATION

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    OFFICIAL USE ONLY KIRTLAND AFB PASS REQUEST SPONSOR'S INFORMATION FIRST NAME MIDDLE NAME LAST NAME SSN or DOD ID Number DATE OF BIRTH SEX M F (circle one) ORGANIZATION ORGANIZATION ...

  2. EIS-0510: Calcasieu Pass Project, Cameron Parish, Louisiana | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Energy 10: Calcasieu Pass Project, Cameron Parish, Louisiana EIS-0510: Calcasieu Pass Project, Cameron Parish, Louisiana SUMMARY The Federal Energy Regulatory Commission (FERC) announced its intent to prepare an EIS that assesses the potential environmental impacts of the construction and operation of 1) a proposed liquefied natural gas (LNG) export terminal; and 2) a 23.8-mile, 42-inch-diameter pipeline in Cameron Parish, Louisiana. DOE is a cooperating agency in preparing the EIS. DOE,

  3. Northern Pass Transmission Line Project Environmental Impact Statement:

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Announcement of Change in Public Meeting Location: Federal Register Notice Volume 78, No. 181 - September 18, 2013 | Department of Energy Northern Pass Transmission Line Project Environmental Impact Statement: Announcement of Change in Public Meeting Location: Federal Register Notice Volume 78, No. 181 - September 18, 2013 Northern Pass Transmission Line Project Environmental Impact Statement: Announcement of Change in Public Meeting Location: Federal Register Notice Volume 78, No. 181 -

  4. 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.

  5. UNITED STATES OF AMERICA FEDERAL ENERGY REGULATORY COMMISSION

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Golden Pass Products, LLC and Docket Nos. CP14-517-000 Golden Pass Pipeline, LLC ... Pass Products, LLC and Golden Pass Pipeline, LLC (collectively referred to as Golden ...

  6. 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}.

  7. General Atomics (GA) Fusion News: A New Spin on Understanding...

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    General Atomics (GA) Fusion News: A New Spin on Understanding Plasma Confinement American Fusion News Category: General Atomics (GA) Link: General Atomics (GA) Fusion News: A New ...

  8. Final Report Bald and Golden Eagle Territory Surveys for the Lawrence Livermore National Laboratory

    SciTech Connect (OSTI)

    Fratanduono, M. L.

    2014-11-25

    Garcia and Associates (GANDA) was contracted by the Lawrence Livermore National Laboratory (LLNL) to conduct surveys for bald eagles (Haliaeetus leucocephalus) and golden eagles (Aquila chrysaetos) at Site 300 and in the surrounding area out to 10-miles. The survey effort was intended to document the boundaries of eagle territories by careful observation of eagle behavior from selected viewing locations throughout the study area.

  9. Standards for message-passing in a distributed memory environment

    SciTech Connect (OSTI)

    Walker, D.W.

    1992-08-01

    This report presents a summary of the main ideas presented at the First CRPC Work-shop on Standards for Message Passing in a Distributed Memory Environment, held April 29-30, 1992, in Williamsburg, Virginia. This workshop attracted 68 attendees including representative from major hardware and software vendors, and was the first in a series of workshops sponsored by the Center for Research on Parallel Computation. The aim of this series of workshops is to develop and implement a standard for message passing on distributed memory concurrent computers, thereby making it easier to develop efficient, portable application codes for such machines. The report discusses the main issues raised in the CRPC workshop, and describes proposed desirable features of a message passing standard for distributed memory environments.

  10. Validation of the G-PASS code : status report.

    SciTech Connect (OSTI)

    Vilim, R. B.; Nuclear Engineering Division

    2009-03-12

    Validation is the process of determining whether the models in a computer code can describe the important phenomena in applications of interest. This report describes past work and proposed future work for validating the Gas Plant Analyzer and System Simulator (G-PASS) code. The G-PASS code was developed for simulating gas reactor and chemical plant system behavior during operational transients and upset events. Results are presented comparing code properties, individual component models, and integrated system behavior against results from four other computer codes. Also identified are two experiment facilities nearing completion that will provide additional data for individual component and integrated system model validation. The main goal of the validation exercise is to ready a version of G-PASS for use as a tool in evaluating vendor designs and providing guidance to vendors on design directions in nuclear-hydrogen applications.

  11. 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

    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.

  12. Opening of the Cheniere Energy Sabine Pass LNG Regasification Facility |

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Department of Energy Cheniere Energy Sabine Pass LNG Regasification Facility Opening of the Cheniere Energy Sabine Pass LNG Regasification Facility April 21, 2008 - 10:49am Addthis Remarks As Prepared for Delivery by Energy Secretary Samuel Bodman Good morning. Charif, thank you for inviting me to be here and thank you for the tour. It's good to see Senator Vitter, Congressman Boustany and Secretary Abraham. And I am pleased we are joined by my good friends from the Federal Energy Regulatory

  13. Passing the baton | Y-12 National Security Complex

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    Passing the baton Passing the baton Posted: February 18, 2014 - 4:57pm Taking on special assignments is part of most jobs, and it's something Chuck Spencer did when he accepted the role as B&W Y-12's president and general manager in August 2012. "What I thought would be a 3-6 month job turned into 18 months," Spencer said. On Feb. 1, Dave Richardson assumed the role as president and general manager of B&W Y-12. "Dave has over 33 years of diverse nuclear operations and

  14. Sabine Pass, LA Liquefied Natural Gas Exports to Dominican Republic

    U.S. Energy Information Administration (EIA) (indexed site)

    (Million Cubic Feet) Dominican Republic (Million Cubic Feet) Sabine Pass, LA Liquefied Natural Gas Exports to Dominican Republic (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2016 2,945 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Liquefied Natural Gas Exports by Point of Exit Sabine Pass, LA Liquefied Natural

  15. Extensible message passing application development and debugging with Python

    SciTech Connect (OSTI)

    Beazley, D.M.; Lomdahl, P.S.

    1996-09-19

    The authors describe how they have parallelized Python, an interpreted object oriented scripting language, and used it to build an extensible message-passing C/C++ applications for the CM-5, Cray T3D, and Sun multiprocessor servers running MPI. Using a parallelized Python interpreter, it is possible to interact with large-scale parallel applications, rapidly prototype new features, and perform application specific debugging. It is even possible to write message passing programs in Python itself. The authors describe some of the tools they have developed to extend Python and applications of this approach.

  16. East Avenue Truck Inspection Patterson Pass Road Vasco Road

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    Vasco Road Thunderbird Lane Greenville Road Greenville Road Directions to the Sandia/CA - Visitor Badge Office Interstate 580 - Oakland/San Francisco, Traveling Eastbound * Exit Vasco Road South * Continue traveling South on Vasco Road for 1.1 miles * Turn left onto Patterson Pass Road * Continue traveling East on Patterson Pass Road for 1.2 miles * Turn right onto Greenville Road * Continue traveling South on Greenville Road for 1.1 miles * Turn right onto East Avenue * Follow the road as it

  17. 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.

  18. Gschneidner's passing recognized in Nature | The Ames Laboratory

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    Gschneidner's passing recognized in Nature Ames Laboratory's late senior metallurgist Karl Gschneidner Jr. was honored by the journal Nature with a full-page tribute summarizing Gschneidner's life-long work with rare earths. The obituary was written by Ames Laboratory scientist and long-time Gschneidner colleague, Vitalij Pecharsky. You can read the article HERE

  19. Message Passing for Linux Clusters with Gigabit Ethernet Mesh Connections

    SciTech Connect (OSTI)

    Jie Chen; Chip Watson; Robert Edwards; Weizhen Mao

    2005-04-01

    Multiple copper-based commodity Gigabit Ethernet (GigE) interconnects (adapters) on a single host can lead to Linux clusters with mesh/torus connections without using expensive switches and high speed network interconnects (NICs). However traditional message passing systems based on TCP for GigE will not perform well for this type of clusters because of the overhead of TCP for multiple GigE links. In this paper, we present two os-bypass message passing systems that are based on a modified M-VIA (an implementation of VIA specification) for two production GigE mesh clusters: one is constructed as a 4 x 8 x 8 (256 nodes) torus and has been in production use for a year; the other is constructed as a 6 x 8 x 8 (384 nodes) torus and was deployed recently. One of the message passing systems targets to a specific application domain and is called QMP and the other is an implementation of MPI specification 1.1. The GigE mesh clusters using these two message passing systems achieve about 18.5 {micro}s half-way round trip latency and 400MB/s total bandwidth, which compare reasonably well to systems using specialized high speed adapters in a switched architecture at much lower costs.

  20. 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.

  1. EA-0995: Drum Storage Facility for Interim Storage of Materials Generated by Environmental Restoration Operations, Golden, Colorado

    Energy.gov [DOE]

    This EA evaluates the environmental impacts of the proposal to construct and operate a drum storage facility at the U.S. Department of Energy's Rocky Flats Environmental Technology Site in Golden,...

  2. DOE Golden Field Office Status of FOIA Requests Received - Fiscal Year (FY) 2015

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Golden Field Office Status of FOIA Requests Received - Fiscal Year (FY) 2015 Docket # Description of FOIA Request Status GO-15-001 "The following documents submitted by New England Aqua Ventus I under DE-EE- 0005990: The Awardee Down-Select Letter - Strengths and Weaknesses Document - SF-424, Statement of Project Objectives dated August 27, 2014 -Monthly Progress Report briefing dated October 2013 -New England Aqua Ventus I responses to DOE Questions dated April 2014" Completed -

  3. NNSA missions now powered by California gold...en sunshine | National

    National Nuclear Security Administration (NNSA)

    Nuclear Security Administration | (NNSA) missions now powered by California gold...en sunshine Friday, March 25, 2016 - 9:54am An NNSA national laboratory is taking advantage of California's blue skies to power critical national security and science research. The solar power system installed at Lawrence Livermore National Laboratory (LLNL) is now fully functional and producing electricity. In 2015, NNSA announced the agreement for a solar electrical generation system onsite at LLNL. The

  4. Golden Reading Room: Request for Proposals (RFP) Number DE-RP36-07GO97036 |

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Department of Energy Request for Proposals (RFP) Number DE-RP36-07GO97036 Golden Reading Room: Request for Proposals (RFP) Number DE-RP36-07GO97036 RFP DE-RP36-07GO97036 -- Management and Operation of the National Renewable Energy Laboratory Alliance Prime Contract No. DE-AC36-08GO28308, through modification 1033

  5. Temperature coefficients for GaInP/GaAs/GaInNAsSb solar cells

    SciTech Connect (OSTI)

    Aho, Arto; Isoaho, Riku; Tukiainen, Antti; Polojärvi, Ville; Aho, Timo; Raappana, Marianna; Guina, Mircea

    2015-09-28

    We report the temperature coefficients for MBE-grown GaInP/GaAs/GaInNAsSb multijunction solar cells and the corresponding single junction sub-cells. Temperature-dependent current-voltage measurements were carried out using a solar simulator equipped with a 1000 W Xenon lamp and a three-band AM1.5D simulator. The triple-junction cell exhibited an efficiency of 31% at AM1.5G illumination and an efficiency of 37–39% at 70x real sun concentration. The external quantum efficiency was also measured at different temperatures. The temperature coefficients up to 80°C, for the open circuit voltage, the short circuit current density, and the conversion efficiency were determined to be −7.5 mV/°C, 0.040 mA/cm{sup 2}/°C, and −0.09%/°C, respectively.

  6. Pulse Analysis Spectroradiometer System (PASS) Software - Energy Innovation

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    Portal Energy Analysis Energy Analysis Find More Like This Return to Search Pulse Analysis Spectroradiometer System (PASS) Software National Renewable Energy Laboratory Contact NREL About This Technology Publications: PDF Document Publication Pulse Analysis Spectroradiometer System for Measuring the Spectral Distribution of Flash Solar Simulators http://www.nrel.gov/docs/fy08osti/43652.pdf (576 KB) Technology Marketing SummaryFlashing artificial light sources are used extensively in

  7. Thermal efficiency of single-pass solar air collector

    SciTech Connect (OSTI)

    Ibrahim, Zamry; Ibarahim, Zahari; Yatim, Baharudin; Ruslan, Mohd Hafidz

    2013-11-27

    Efficiency of a finned single-pass solar air collector was studied. This paper presents the experimental study to investigate the effect of solar radiation and mass flow rate on efficiency. The fins attached at the back of absorbing plate to improve the thermal efficiency of the system. The results show that the efficiency is increased proportional to solar radiation and mass flow rate. Efficiency of the collector archived steady state when reach to certain value or can be said the maximum performance.

  8. Sabine Pass, LA Liquefied Natural Gas Exports (Million Cubic Feet)

    U.S. Energy Information Administration (EIA) (indexed site)

    (Million Cubic Feet) Sabine Pass, LA Liquefied Natural Gas Exports (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2016 3,284 10,052 10,010 9,840 16,421 15,703 26,727 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S.

  9. A compact double-pass Raman backscattering amplifier/compressor

    SciTech Connect (OSTI)

    Ren, J.; Li, S.; Morozov, A.; Suckewer, S.; Yampolsky, N. A.; Malkin, V. M.; Fisch, N. J.

    2008-05-15

    The enhancement of stimulated Raman backscattering (SRBS) amplification was demonstrated by introducing a plasma density gradient along the pump and the seed interaction path and by a novel double-pass design. The energy transfer efficiency was significantly improved to a level of 6.4%. The seed pulse was amplified by a factor of more than 20 000 from the input in a 2 mm long plasma, which also exceeded the intensity of the pump pulse by 2 orders of magnitude. This was accompanied by very effective pulse compression, from 500 fs to 90 fs in the first pass measurements and in the second pass down to approximately 50 fs, as it is indicated by the energy-pulse duration relation. Further improvements to the energy transfer efficiency and the SRBS performance by extending the region of resonance is also discussed where a uniform {approx}4 mm long plasma channel for SRBS was generated by using two subsequent laser pulses in an ethane gas jet.

  10. One pass core design of a super fast reactor

    SciTech Connect (OSTI)

    Liu, Qingjie; Oka, Yoshiaki

    2013-07-01

    One pass core design for Supercritical-pressure light water-cooled fast reactor (Super FR) is proposed. The whole core is cooled with upward flow in one through flow pattern like PWR. Compared with the previous two pass core design; this new flow pattern can significantly simplify the core concept. Upper core structure, coolant flow scheme as well as refueling procedure are as simple as in PWR. In one pass core design, supercritical-pressure water is at approximately 25.0 MPa and enters the core at 280 C. degrees and is heated up in one through flow pattern upwardly to the average outlet temperature of 500 C. degrees. Great density change in vertical direction can cause significant axial power offset during the cycle. Meanwhile, Pu accumulated in the UO{sub 2} fuel blanket assemblies also introduces great power increase during cycle, which requires large amount of flow for heat removal and makes the outlet temperature of blanket low at the beginning of equilibrium cycle (BOEC). To deal with these issues, some MOX fuel is applied in the bottom region of the blanket assembly. This can help to mitigate the power change in blanket due to Pu accumulation and to increase the outlet temperature of the blanket during cycle. Neutron transport and thermohydraulics coupled calculation shows that this design can satisfy the requirement in the Super FR principle for both 500 C. degrees outlet temperature and negative coolant void reactivity. (authors)

  11. Incentive Pass-through for Residential Solar Systems in California

    Office of Energy Efficiency and Renewable Energy (EERE)

    The deployment of solar photovoltaic (PV) systems has grown rapidly over the last decade, partly because of various government incentives. In the United States, those established in California are among the largest and longest-running incentives. Building on past research, this report addresses the still-unanswered question: to what degree have the direct PV incentives in California been passed along from installers to consumers? This report addresses this question by carefully examining the residential PV market in California and applying both a structural-modeling approach and a reduced-form regression analysis to estimate the incentive pass-through rate. The results suggest an average pass-through rate of direct incentives of nearly 100%, but with regional differences among California counties. While these results could have multiple explanations, they suggest a relatively competitive market and well-functioning subsidy program. Further analysis is required to determine whether similar results broadly apply to other states, to other customer segments, to all third-party-owned PV systems, or to all forms of financial incentives for solar.

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

    DOE Patents [OSTI]

    Kurtz, Steven R.; Allerman, Andrew A.; Klem, John F.; Jones, Eric D.

    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%.

  13. 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.

  14. 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

    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.

  15. EA-1983: Sabine Pass Liquefaction Expansion Project, Cameron Parish, Louisiana

    Energy.gov [DOE]

    The Federal Energy Regulatory Commission (FERC) is preparing an EA for a proposal to expand the existing Sabine Pass Liquefied Natural Gas Terminal in Cameron Parish, and to extend an associated existing pipeline system in Cameron, Calcasieu, Beauregard, Allen, and Evangeline Parishes in Louisiana. DOE is a cooperating agency in preparing the EA. DOE, Office of Fossil Energy, has an obligation under Section 3 of the Natural Gas Act to authorize the import and export of natural gas, including LNG, unless it finds that the import or export is not consistent with the public interest.

  16. 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 kp 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 . The joint density of states and optical absorption of a 40/40 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.

  17. Optical and magnetotransport properties of InGaAs/GaAsSb/GaAs structures doped with a magnetic impurity

    SciTech Connect (OSTI)

    Kalentyeva, I. L. Zvonkov, B. N.; Vikhrova, O. V.; Danilov, Yu. A.; Demina, P. B.; Dorokhin, M. V.; Zdoroveyshchev, A. V.

    2015-11-15

    InGaAs/GaAsSb/GaAs bilayer quantum-well structures containing a magnetic-impurity δ-layer (Mn) at the GaAs/InGaAs interface are experimentally studied for the first time. The structures are fabricated by metal organic chemical-vapor deposition (MOCVD) and laser deposition on substrates of conducting (n{sup +}) and semi-insulating GaAs in a single growth cycle. The InGaAs-layer thickness is varied from 1.5 to 5 nm. The significant effect of a decrease in the InGaAs quantum-well thickness on the optical and magnetotransport properties of the structures under study is detected. Nonlinear magnetic-field dependence of the Hall resistance and negative magnetoresistance at temperatures of ≤30–40 K, circular polarization of the electroluminescence in a magnetic field, opposite behaviors of the photoluminescence and electroluminescence emission intensities in the structures, and an increase in the contribution of indirect transitions with decreasing InGaAs thickness are observed. Simulation shows that these effects can be caused by the influence of the δ-layer of acceptor impurity (Mn) on the band structure and the hole concentration distribution in the bilayer quantum well.

  18. A cryogenic circulating advective multi-pass absorption cell

    SciTech Connect (OSTI)

    Stockett, M. H.; Lawler, J. E. [Department of Physics, University of Wisconsin, 1150 University Avenue, Madison, Wisconsin 53706 (United States)

    2012-03-15

    A novel absorption cell has been developed to enable a spectroscopic survey of a broad range of polycyclic aromatic hydrocarbons (PAH) under astrophysically relevant conditions and utilizing a synchrotron radiation continuum to test the still controversial hypothesis that these molecules or their ions could be carriers of the diffuse interstellar bands. The cryogenic circulating advective multi-pass absorption cell resembles a wind tunnel; molecules evaporated from a crucible or injected using a custom gas feedthrough are entrained in a laminar flow of cryogenically cooled buffer gas and advected into the path of the synchrotron beam. This system includes a multi-pass optical White cell enabling absorption path lengths of hundreds of meters and a detection sensitivity to molecular densities on the order of 10{sup 7} cm{sup -3}. A capacitively coupled radio frequency dielectric barrier discharge provides ionized and metastable buffer gas atoms for ionizing the candidate molecules via charge exchange and the Penning effect. Stronger than expected clustering of PAH molecules has slowed efforts to record gas phase PAH spectra at cryogenic temperatures, though such clusters may play a role in other interstellar phenomena.

  19. The Super Efficient Refrigerator Program: Case study of a Golden Carrot program

    SciTech Connect (OSTI)

    Eckert, J B

    1995-07-01

    The work in this report was conducted by the Analytic Studies Division (ASD) of the National Renewable Energy Laboratory (NREL) for the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy, Office of Building Technologies. This case study describes the development and implementation of the Super Efficient Refrigerator Program (SERP), which awarded $30 million to the refrigerator manufacturer that developed and commercialized a refrigerator that exceeded 1993 federal efficiency standards by at least 25%. The program was funded by 24 public and private utilities. As the first Golden Carrot program to be implemented in the United States, SERP was studied as an example for future `market-pull` efforts.

  20. CPV Cell Characterization Following One-Year Exposure in Golden, Colorado: Preprint

    SciTech Connect (OSTI)

    Bosco, N.; Kurtz, S.

    2014-08-01

    A CPV module containing 30 III-V multijunction cells was operated on?sun for one year in Golden, Colorado. Each cell was characterized prior to and following exposure. A module power degradation of 10% was observed and found to be a result as an overall decrease in cell short circuit current and the presence of at least one shunted cell. A positive correlation between initial shunt current and an increase in shunt current following exposure was also found. Cell exfoliation was also observed and found to be coincident with the presence of water and/or charring of the cell package due to an off-sun event.

  1. 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.

  2. Degradation mechanisms of 2 MeV proton irradiated AlGaN/GaN HEMTs...

    Office of Scientific and Technical Information (OSTI)

    irradiated AlGaNGaN HEMTs This content will become publicly available on August 26, 2016 Title: Degradation mechanisms of 2 MeV proton irradiated AlGaNGaN HEMTs Authors: ...

  3. (In,Ga)As/GaP electrical injection quantum dot laser

    SciTech Connect (OSTI)

    Heidemann, M. Höfling, S.; Kamp, M.

    2014-01-06

    The paper reports on the realization of multilayer (In,Ga)As/GaP quantum dot (QD) lasers grown by gas source molecular beam epitaxy. The QDs have been embedded in (Al,Ga)P/GaP waveguide structures. Laser operation at 710 nm is obtained for broad area laser devices with a threshold current density of 4.4 kA/cm{sup 2} at a heat-sink temperature of 80 K.

  4. US SoAtl GA Site Consumption

    U.S. Energy Information Administration (EIA) (indexed site)

    GA Site Consumption million Btu $0 $500 $1,000 $1,500 $2,000 $2,500 US SoAtl GA Expenditures dollars ALL ENERGY average per household (excl. transportation) 0 4,000 8,000 12,000 16,000 US SoAtl GA Site Consumption kilowatthours $0 $300 $600 $900 $1,200 $1,500 $1,800 US SoAtl GA Expenditures dollars ELECTRICITY ONLY average per household * Site energy consumption (89.5 million Btu) and energy expenditures per household ($2,067) in Georgia are similar to the U.S. household averages. * Per

  5. Amended Application for Presidential Permit OE Docket No: PP–371 Northern Pass Transmission LLC

    Energy.gov [DOE]

    Northern Pass Transmission LLC (Northern Pass) has submitted an amended application for a Presidential permit to construct, operate, maintain, and connect an electric transmission line across the United States border with Canada.

  6. Sabine Pass Liquefaction, LLC FE Dkt. No 15-171-LNG

    Energy.gov [DOE]

    The Office of Fossil Energy (FE) of the Department of Energy (DOE) gives notice of receipt of an application (Application), filed on November 6, 2015, by Sabine Pass Liquefaction, LLC (Sabine Pass)...

  7. Sabine Pass, LA Natural Gas LNG Imports (Price) From Peru (Dollars...

    Annual Energy Outlook

    Sabine Pass, LA Natural Gas LNG Imports (Price) From Peru (Dollars per Thousand Cubic Feet) Sabine Pass, LA Natural Gas LNG Imports (Price) From Peru (Dollars per Thousand Cubic ...

  8. Price of Sabine Pass, LA Natural Gas LNG Imports from Nigeria...

    Gasoline and Diesel Fuel Update

    Sabine Pass, LA Natural Gas LNG Imports from Nigeria (Dollars per Thousand Cubic Feet) Price of Sabine Pass, LA Natural Gas LNG Imports from Nigeria (Dollars per Thousand Cubic ...

  9. Price of Savine Pass, LA Natural Gas LNG Imports from Egypt ...

    Gasoline and Diesel Fuel Update

    Savine Pass, LA Natural Gas LNG Imports from Egypt (Nominal Dollars per Thousand Cubic Feet) Price of Savine Pass, LA Natural Gas LNG Imports from Egypt (Nominal Dollars per ...

  10. Development of a Single-Pass Cut-and-Chip Harvest System for...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Single-Pass Cut-and-Chip Harvest System for Short Rotation Woody Crops Development of a Single-Pass Cut-and-Chip Harvest System for Short Rotation Woody Crops Breakout Session ...

  11. PIA - WEB iPASS System DOE PIA | Department of Energy

    Energy.gov (indexed) [DOE]

    PIA - WEB iPASS System DOE PIA PDF icon PIA - WEB iPASS System DOE PIA More Documents & Publications PIA - INL Education Programs Business Enclave Integrated Safety Management ...

  12. SEMI-ANNUAL REPORTS FOR VENTURE GLOBAL CALCASIEU PASS, LLC (formerly...

    Energy.gov (indexed) [DOE]

    Venture Global Calcasieu Pass, LLC - FE Dkt. No. - 15-25-LNG Venture Global Calcasieu Pass, LLC - (Formerly Venture Global LNG, LLC) - 14-88-LNG Comments, Protests and ...

  13. SEMI-ANNUAL REPORTS FOR MAIN PASS ENERGY HUB, LLC - FE DKT. NO...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    MAIN PASS ENERGY HUB, LLC - FE DKT. NO. 12-114-LNG - ORDER 3220 SEMI-ANNUAL REPORTS FOR MAIN PASS ENERGY HUB, LLC - FE DKT. NO. 12-114-LNG - ORDER 3220 PDF icon April 2014 PDF icon ...

  14. PIA - WEB iPASS System DOE PIA | Department of Energy

    Energy.gov (indexed) [DOE]

    iPASS System DOE PIA PIA - WEB iPASS System DOE PIA (304.89 KB) More Documents & Publications PIA - INL Education Programs Business Enclave Integrated Safety Management Workshop ...

  15. Public Hearings on Northern Pass Draft EIS Announced

    Energy.gov [DOE]

    The U.S. Department of Energy (DOE) has announced public hearings to receive comments on the Draft EIS (DOE/EIS–0463). The Draft EIS evaluates the potential environmental impacts of DOE’s proposed Federal action of issuing a Presidential permit to Northern Pass LLC (the Applicant) to construct, operate, maintain, and connect a new electric transmission line across the U.S./Canada border in northern New Hampshire. For the convenience of the public, DOE in conjunction with the New Hampshire SEC will conduct public hearings to provide the public with information on the proposed project and an opportunity for the public to provide oral and written comments and to ask questions concerning the project on March 7 and March 10, 2016.

  16. 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%.

  17. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Anne Moschella

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  18. Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Fred Brownson

    Energy.gov [DOE]

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  19. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Jim Cannon

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  20. Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Elisha Gray

    Energy.gov [DOE]

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  1. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Robert Cote

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  2. Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Robert Martin

    Energy.gov [DOE]

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  3. Energy Department Authorizes Sabine Pass Liquefaction’s Expansion Project to Export Liquefied Natural Gas

    Office of Energy Efficiency and Renewable Energy (EERE)

    A press release on the final authorization to allow Sabine Pass Liquefaction, LLC to export liquefied natural gas (LNG).

  4. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from James Kennedy

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  5. Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from John Brodeer

    Office of Energy Efficiency and Renewable Energy (EERE)

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  6. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from The Nature Conservancy

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  7. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Gina Neily

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  8. Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Joseph Keenan

    Energy.gov [DOE]

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  9. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Ann Vennerbeck

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  10. Application for Presidential Permit OE Docket No. PP-371 Northern Pass

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Transmission LLC | Department of Energy Transmission LLC Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission LLC Amended application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border. PP-371 Northern Pass Amended Application 08-31-15.pdf (674.94 KB) More Documents & Publications Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Linda Upham

  11. Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Alice Peatman

    Energy.gov [DOE]

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  12. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Campton Conservation Commission

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S, - Canada Border.

  13. Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Linda Upham

    Energy.gov [DOE]

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  14. Application for Presidential Permit OE Docket No. PP-371 Northern Pass:

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Comments from Lindsey Coombs | Department of Energy Lindsey Coombs Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Lindsey Coombs Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border. Coombs_NorthernPass_Intervention.pdf (16.36 KB) More Documents & Publications Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Ann Vennerbeck Application for

  15. Application for Presidential Permit OE Docket No. PP-371 Northern Pass:

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Comments from Maureen Quinn | Department of Energy Maureen Quinn Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Maureen Quinn Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border. Quinn_NorthernPass_Intervention.pdf (24.36 KB) More Documents & Publications Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Anne Moschella Application for

  16. Application for Presidential Permit OE Docket No. PP-371 Northern Pass:

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Comments from Michelle Kleindienst | Department of Energy Michelle Kleindienst Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Michelle Kleindienst Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border. Kleindienst_NorthernPass_Intervention.pdf (82.94 KB) More Documents & Publications Application for Presidential Permit OE Docket No: PP-371 Northern Pass Transmission: Comments

  17. Application for Presidential Permit OE Docket No. PP-371 Northern Pass:

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Comments from Pamela Hanglin | Department of Energy Hanglin Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Pamela Hanglin Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border. Hanglin_NorthernPass_Intervention.pdf (22.08 KB) More Documents & Publications Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Pamela Hayes Application for

  18. Application for Presidential Permit OE Docket No. PP-371 Northern Pass:

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Comments from Taras Kucman | Department of Energy Taras Kucman Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Taras Kucman Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border. Kucman_NorthernPass_Intervention.pdf (26.9 KB) More Documents & Publications Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Michelle Kleindienst Application for

  19. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from John Doane Sr.

    Office of Energy Efficiency and Renewable Energy (EERE)

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  20. Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Mary Bearor

    Energy.gov [DOE]

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  1. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Courtney Kearley

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  2. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Erick Berglund, Jr.

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  3. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Steve Nogueira

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  4. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Rana Klug

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  5. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Susan Seitz

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  6. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Roy Kjendal

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  7. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Nicholas Karakoudas

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  8. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Vickie Bedard

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  9. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Lorna Rose

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  10. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Serita Frey

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  11. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Pamela Hayes

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  12. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Bruce Adami

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  13. Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Updated Opinion of Counsel

    Energy.gov [DOE]

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  14. Best Management Practice #9: Single-Pass Cooling Equipment | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Energy 9: Single-Pass Cooling Equipment Best Management Practice #9: Single-Pass Cooling Equipment Single-pass or once-through cooling systems provide an opportunity for significant water savings. In these systems, water is circulated once through a piece of equipment and is then disposed down the drain. Types of equipment that typically use single-pass cooling include CAT scanners, degreasers, hydraulic equipment, condensers, air compressors, welding machines, vacuum pumps, ice machines,

  15. Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Karen Skurka

    Energy.gov [DOE]

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  16. Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Fran Buteau

    Energy.gov [DOE]

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  17. EIS-0476: Vogtle Electric Generating Plant in Burke County, GA...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    6: Vogtle Electric Generating Plant in Burke County, GA EIS-0476: Vogtle Electric Generating Plant in Burke County, GA EIS-0476: Final Environmental Impact Statement EIS-0476: ...

  18. A hole modulator for InGaN/GaN light-emitting diodes

    SciTech Connect (OSTI)

    Zhang, Zi-Hui; Kyaw, Zabu; Liu, Wei; Ji, Yun; Wang, Liancheng; Tan, Swee Tiam; Sun, Xiao Wei E-mail: VOLKAN@stanfordalumni.org; Demir, Hilmi Volkan E-mail: VOLKAN@stanfordalumni.org

    2015-02-09

    The low p-type doping efficiency of the p-GaN layer has severely limited the performance of InGaN/GaN light-emitting diodes (LEDs) due to the ineffective hole injection into the InGaN/GaN multiple quantum well (MQW) active region. The essence of improving the hole injection efficiency is to increase the hole concentration in the p-GaN layer. Therefore, in this work, we have proposed a hole modulator and studied it both theoretically and experimentally. In the hole modulator, the holes in a remote p-type doped layer are depleted by the built-in electric field and stored in the p-GaN layer. By this means, the overall hole concentration in the p-GaN layer can be enhanced. Furthermore, the hole modulator is adopted in the InGaN/GaN LEDs, which reduces the effective valance band barrier height for the p-type electron blocking layer from ?332?meV to ?294?meV at 80?A/cm{sup 2} and demonstrates an improved optical performance, thanks to the increased hole concentration in the p-GaN layer and thus the improved hole injection into the MQWs.

  19. AlGaN/GaN heterostructure prepared on a Si (110) substrate via pulsed sputtering

    SciTech Connect (OSTI)

    Watanabe, T.; Ohta, J.; Kondo, T.; Ohashi, M.; Ueno, K.; Kobayashi, A.; Fujioka, H.

    2014-05-05

    GaN films were grown on Si (110) substrates using a low-temperature growth technique based on pulsed sputtering. Reduction of the growth temperature suppressed the strain in the GaN films, leading to an increase in the critical thickness for crack formation. In addition, an AlGaN/GaN heterostructure with a flat heterointerface was prepared using this technique. Furthermore, the existence of a two dimensional electron gas at the heterointerface with a mobility of 1360 cm{sup 2}/Vs and a sheet carrier density of 1.3??10{sup 13}?cm{sup ?2} was confirmed. Finally, the use of the AlGaN/GaN heterostructure in a high electron mobility transistor was demonstrated. These results indicate that low-temperature growth via pulsed sputtering is quite promising for the fabrication of GaN-based electronic devices.

  20. Metal-interconnection-free integration of InGaN/GaN light emitting diodes with AlGaN/GaN high electron mobility transistors

    SciTech Connect (OSTI)

    Liu, Chao; Cai, Yuefei; Liu, Zhaojun; Ma, Jun; Lau, Kei May

    2015-05-04

    We report a metal-interconnection-free integration scheme for InGaN/GaN light emitting diodes (LEDs) and AlGaN/GaN high electron mobility transistors (HEMTs) by combining selective epi removal (SER) and selective epitaxial growth (SEG) techniques. SER of HEMT epi was carried out first to expose the bottom unintentionally doped GaN buffer and the sidewall GaN channel. A LED structure was regrown in the SER region with the bottom n-type GaN layer (n-electrode of the LED) connected to the HEMTs laterally, enabling monolithic integration of the HEMTs and LEDs (HEMT-LED) without metal-interconnection. In addition to saving substrate real estate, minimal interface resistance between the regrown n-type GaN and the HEMT channel is a significant improvement over metal-interconnection. Furthermore, excellent off-state leakage characteristics of the driving transistor can also be guaranteed in such an integration scheme.

  1. Sound generation by a centrifugal pump at blade passing frequency

    SciTech Connect (OSTI)

    Morgenroth, M.; Weaver, D.S.

    1996-12-01

    This paper reports the results of an experimental study of the pressure pulsations produced by a centrifugal volute pump at its blade passing frequency and their amplification by acoustic resonance in a connected piping system. Detailed measurements were made of the pressure fluctuations in the piping as a function of pump speed and flow rate. A semi-empirical model was used to separate acoustic standing waves from hydraulic pressure fluctuations. The effects of modifying the cut-water geometry were also studied, including the use of flow visualization to observe the flow behavior at the cut-water. The results suggest that the pump may act as an acoustic pressure or velocity source, depending on the flow rate. At conditions of acoustic resonance, the pump acted as an open termination of the piping, i.e., as a node in the acoustic pressure standing waves. Rounding the cut-water had the effect of reducing the amplitude of acoustic resonance, apparently because of the ability of the stagnation point to move and thereby reduce the vorticity generated. A notable example of this acoustic resonance in the Primary Heat Transport (PHT) system at Ontario Hydro`s Darlington nuclear power station.

  2. Message passing with a limited number of DMA byte counters

    SciTech Connect (OSTI)

    Blocksome, Michael; Chen, Dong; Giampapa, Mark E.; Heidelberger, Philip; Kumar, Sameer; Parker, Jeffrey J.

    2011-10-04

    A method for passing messages in a parallel computer system constructed as a plurality of compute nodes interconnected as a network where each compute node includes a DMA engine but includes only a limited number of byte counters for tracking a number of bytes that are sent or received by the DMA engine, where the byte counters may be used in shared counter or exclusive counter modes of operation. The method includes using rendezvous protocol, a source compute node deterministically sending a request to send (RTS) message with a single RTS descriptor using an exclusive injection counter to track both the RTS message and message data to be sent in association with the RTS message, to a destination compute node such that the RTS descriptor indicates to the destination compute node that the message data will be adaptively routed to the destination node. Using one DMA FIFO at the source compute node, the RTS descriptors are maintained for rendezvous messages destined for the destination compute node to ensure proper message data ordering thereat. Using a reception counter at a DMA engine, the destination compute node tracks reception of the RTS and associated message data and sends a clear to send (CTS) message to the source node in a rendezvous protocol form of a remote get to accept the RTS message and message data and processing the remote get (CTS) by the source compute node DMA engine to provide the message data to be sent.

  3. Carrier quenching in InGaP/GaAs double heterostructures

    SciTech Connect (OSTI)

    Wells, Nathan P. Driskell, Travis U.; Hudson, Andrew I.; LaLumondiere, Stephen D.; Lotshaw, William T.; Forbes, David V.; Hubbard, Seth M.

    2015-08-14

    Photoluminescence measurements on a series of GaAs double heterostructures demonstrate a rapid quenching of carriers in the GaAs layer at irradiance levels below 0.1 W/cm{sup 2} in samples with a GaAs-on-InGaP interface. These results indicate the existence of non-radiative defect centers at or near the GaAs-on-InGaP interface, consistent with previous reports showing the intermixing of In and P when free As impinges on the InGaP surface during growth. At low irradiance, these defect centers can lead to sub-ns carrier lifetimes. The defect centers involved in the rapid carrier quenching can be saturated at higher irradiance levels and allow carrier lifetimes to reach hundreds of nanoseconds. To our knowledge, this is the first report of a nearly three orders of magnitude decrease in carrier lifetime at low irradiance in a simple double heterostructure. Carrier quenching occurs at irradiance levels near the integrated Air Mass Zero (AM0) and Air Mass 1.5 (AM1.5) solar irradiance. Additionally, a lower energy photoluminescence band is observed both at room and cryogenic temperatures. The temperature and time dependence of the lower energy luminescence is consistent with the presence of an unintentional InGaAs or InGaAsP quantum well that forms due to compositional mixing at the GaAs-on-InGaP interface. Our results are of general interest to the photovoltaic community as InGaP is commonly used as a window layer in GaAs based solar cells.

  4. Accelerated aging of GaAs concentrator solar cells

    SciTech Connect (OSTI)

    Gregory, P.E.

    1982-04-01

    An accelerated aging study of AlGaAs/GaAs solar cells has been completed. The purpose of the study was to identify the possible degradation mechanisms of AlGaAs/GaAs solar cells in terrestrial applications. Thermal storage tests and accelerated AlGaAs corrosion studies were performed to provide an experimental basis for a statistical analysis of the estimated lifetime. Results of this study suggest that a properly designed and fabricated AlGaAs/GaAs solar cell can be mechanically rugged and environmentally stable with projected lifetimes exceeding 100 years.

  5. Making manufacturers responsible for recycling: Passing the garbage buck

    SciTech Connect (OSTI)

    Chilton, K.; Boerner, C.; Ansehl-Fellow, J.

    1995-09-01

    During a meeting with the Conference of Mayor and the National Association of Counties in April of 1993, Senator Max Baucus, then-Chairman of the Senate Environment and Public Works Committee, unveiled his solution to America`s {open_quotes}garbage crisis{close_quotes}. Modeled after Germany`s draconian {open_quotes}green dot{close_quotes} recycling program, the Senator`s solution rested on a principle which he called {open_quotes}manufacturers` responsibility for the life-cycle of a product.{close_quotes} {open_quotes}Anyone who sells a product,{close_quotes} Senator Baucus noted, {open_quotes}should also be responsible for the product when it becomes waste{close_quotes}. Other variations on this life-cycle stewardship concept were a central element of Congress`s failed attempts in 1992-1993 to reauthorize the Resource Conservation and Recovery Act (RCRA). Likewise, on July 11, 1994 the United States Conference of Mayors` Energy and Environment Committee passed a resolution calling on Congress to study the concept of {open_quotes}shared responsibility for waste reduction{close_quotes}. The committee cited the virtues of Western Europe`s systems of manufacturers` responsibility and claimed that a U.S. version would create jobs, promote new environmental technology and {open_quotes}result in the emergence of entire new industries{close_quotes}. This report describes a recycling program in Germany in which the manaufacturers are responsible for waste collection. The overall waste reduction benefits are described.

  6. Synthesis, morphology and optical properties of GaN and AlGaN semiconductor nanostructures

    SciTech Connect (OSTI)

    Kuppulingam, B. Singh, Shubra Baskar, K.

    2014-04-24

    Hexagonal Gallium Nitride (GaN) and Aluminum Gallium Nitride (AlGaN) nanoparticles were synthesized by sol-gel method using Ethylene Diamine Tetra Acetic acid (EDTA) complex route. Powder X-ray diffraction (PXRD) analysis confirms the hexagonal wurtzite structure of GaN and Al{sub 0.25}Ga{sub 0.75}N nanoparticles. Surface morphology and elemental analysis were carried out by Scanning Electron Microscope (SEM) and Energy Dispersive X-ray spectroscopy (EDX). The room temperature Photoluminescence (PL) study shows the near band edge emission for GaN at 3.35 eV and at 3.59 eV for AlGaN nanoparticles. The Aluminum (Al) composition of 20% has been obtained from PL emission around 345 nm.

  7. Zinc blende GaAs films grown on wurtzite GaN/sapphire templates

    SciTech Connect (OSTI)

    Chaldyshev, V.V.; Nielsen, B.; Mendez, E.E.; Musikhin, Yu.G.; Bert, N.A.; Ma, Zh.; Holden, Todd

    2005-03-28

    1-{mu}m-thick zinc-blende GaAs (111) films were grown by molecular-beam epitaxy on wurtzite GaN/sapphire (0001) templates. In spite of a {approx}20% lattice mismatch, epitaxial growth was realized, so that the GaAs films showed good adhesion and their surface had a larger mirror-like area with an average surface roughness of 10 nm. Transmission electron microscopy revealed a flat and abrupt epitaxial GaAs/GaN interface with some nanocavities and a large number of dislocations. Reasonably good crystalline quality of the GaAs films was confirmed by Raman characterization. Spectroscopic ellipsometry showed sharp interference fringes and characteristic parameters in the range of 0.75-5.3 eV. Photoluminescence study revealed extended band tails and dominance of non-radiative carrier recombination.

  8. High-performance InGaP/GaAs pnp {delta}-doped heterojunction bipolar transistor

    SciTech Connect (OSTI)

    Tsai, J.-H. Chiu, S.-Y.; Lour, W.-S.; Guo, D.-F.

    2009-07-15

    In this article, a novel InGaP/GaAs pnp {delta}-doped heterojunction bipolar transistor is first demonstrated. Though the valence band discontinuity at InGaP/GaAs heterojunction is relatively large, the addition of a {delta}-doped sheet between two spacer layers at the emitter-base (E-B) junction effectively eliminates the potential spike and increases the confined barrier for electrons, simultaneously. Experimentally, a high current gain of 25 and a relatively low E-B offset voltage of 60 mV are achieved. The offset voltage is much smaller than the conventional InGaP/GaAs pnp HBT. The proposed device could be used for linear amplifiers and low-power complementary integrated circuit applications.

  9. Oxidation of ultrathin GaSe

    SciTech Connect (OSTI)

    Thomas Edwin Beechem; McDonald, Anthony E.; Ohta, Taisuke; Howell, Stephen W.; Kalugin, Nikolai G.; Kowalski, Brian M.; Brumbach, Michael T.; Spataru, Catalin D.; Pask, Jesse A.

    2015-10-26

    Oxidation of exfoliated gallium selenide (GaSe) is investigated through Raman, photoluminescence, Auger, and X-ray photoelectron spectroscopies. Photoluminescence and Raman intensity reductions associated with spectral features of GaSe are shown to coincide with the emergence of signatures emanating from the by-products of the oxidation reaction, namely, Ga2Se3 and amorphous Se. Furthermore, photoinduced oxidation is initiated over a portion of a flake highlighting the potential for laser based patterning of two-dimensional heterostructures via selective oxidation.

  10. Oxidation of ultrathin GaSe

    DOE PAGES-Beta [OSTI]

    Thomas Edwin Beechem; McDonald, Anthony E.; Ohta, Taisuke; Howell, Stephen W.; Kalugin, Nikolai G.; Kowalski, Brian M.; Brumbach, Michael T.; Spataru, Catalin D.; Pask, Jesse A.

    2015-10-26

    Oxidation of exfoliated gallium selenide (GaSe) is investigated through Raman, photoluminescence, Auger, and X-ray photoelectron spectroscopies. Photoluminescence and Raman intensity reductions associated with spectral features of GaSe are shown to coincide with the emergence of signatures emanating from the by-products of the oxidation reaction, namely, Ga2Se3 and amorphous Se. Furthermore, photoinduced oxidation is initiated over a portion of a flake highlighting the potential for laser based patterning of two-dimensional heterostructures via selective oxidation.

  11. Highly uniform, multi-stacked InGaAs/GaAs quantum dots embedded in a GaAs nanowire

    SciTech Connect (OSTI)

    Tatebayashi, J. Ota, Y.; Ishida, S.; Nishioka, M.; Iwamoto, S.; Arakawa, Y.

    2014-09-08

    We demonstrate a highly uniform, dense stack of In{sub 0.22}Ga{sub 0.78}As/GaAs quantum dot (QD) structures in a single GaAs nanowire (NW). The size (and hence emission energy) of individual QD is tuned by careful control of the growth conditions based on a diffusion model of morphological evolution of NWs and optical characterization. By carefully tailoring the emission energies of individual QD, dot-to-dot inhomogeneous broadening of QD stacks in a single NW can be as narrow as 9.3?meV. This method provides huge advantages over traditional QD stack using a strain-induced Stranski-Krastanow growth scheme. We show that it is possible to fabricate up to 200 uniform QDs in single GaAs NWs using this growth technique without degradation of the photoluminescence intensity.

  12. Simplified 2DEG carrier concentration model for composite barrier AlGaN/GaN HEMT

    SciTech Connect (OSTI)

    Das, Palash Biswas, Dhrubes

    2014-04-24

    The self consistent solution of Schrodinger and Poisson equations is used along with the total charge depletion model and applied with a novel approach of composite AlGaN barrier based HEMT heterostructure. The solution leaded to a completely new analytical model for Fermi energy level vs. 2DEG carrier concentration. This was eventually used to demonstrate a new analytical model for the temperature dependent 2DEG carrier concentration in AlGaN/GaN HEMT.

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

    SciTech Connect (OSTI)

    Hudait, M. K.; Zhu, Y.; Johnston, S. W.; Maurya, D.; Priya, S.; Umbel, R.

    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.

  14. Magnetic coupling in ferromagnetic semiconductor (Ga,Mn)As/(Al,Ga,Mn)As bilayers

    SciTech Connect (OSTI)

    Wang, M.; Wadley, P.; Campion, R. P.; Rushforth, A. W.; Edmonds, K. W.; Gallagher, B. L.; Charlton, T. R.; Kinane, C. J.; Langridge, S.

    2015-08-07

    We report on a study of ferromagnetic semiconductor (Ga,Mn)As/(Al,Ga,Mn)As bilayers using magnetometry and polarized neutron reflectivity (PNR). From depth-resolved characterization of the magnetic structure obtained by PNR, we concluded that the (Ga,Mn)As and (Al,Ga,Mn)As layers have in-plane and perpendicular-to-plane magnetic easy axes, respectively, with weak interlayer coupling. Therefore, the layer magnetizations align perpendicular to each other under low magnetic fields and parallel at high fields.

  15. US SoAtl GA Site Consumption

    Annual Energy Outlook

    ... Yes Yes No No 0% 20% 40% 60% 80% 100% US GA No Car CAR IS PARKED WITHIN 20 FT OF ELECTRICAL OUTLET More highlights from RECS on housing characteristics and energy-related ...

  16. Princeton Plasma Physics Lab - General Atomics (GA)

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    general-atomics-ga General Atomics en The Scorpion's Strategy: "Catch and Subdue" http:www.pppl.govnode1132

  17. Application for presidential permit OE Docket No. PP-371 Northern Pass

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Transmission LLC | Department of Energy LLC Application for presidential permit OE Docket No. PP-371 Northern Pass Transmission LLC Pursuant to Executive Order (EO) No. 10485, as amended by EO 12038, and 10 C.F.R. § 205.320 et seq., Northern Pass Transmission LLC (Northern Pass or the Applicant) hereby applies to the United States Department of Energy (DOE) for a Presidential Permit authorizing the construction, connection, operation, and maintenance of facilities for the transmission of

  18. Application for presidential permit OE Docket No. PP-371 Northern Pass

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Transmission LLC: Letter of MOU Cancellation | Department of Energy Letter of MOU Cancellation Application for presidential permit OE Docket No. PP-371 Northern Pass Transmission LLC: Letter of MOU Cancellation March 7, 2011 Northern Pass Transmission LLC appreciates the cooperation of the Department of Energy ("DOE") in negotiating the Memorandum of Understanding ("MOU") among DOE, Northern Pass and Normandeau Associates Inc. We nevertheless have concluded that it is

  19. Application for Presidential Permit OE Docket No. PP-371 Northern Pass

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Transmission: Comments from Larry Rappaport | Department of Energy Larry Rappaport Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Larry Rappaport Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border. LarryRappaport_PP-371Comments.pdf (20.87 KB) More Documents & Publications Application for Presidential Permit OE Docket No. PP-371 Northern Pass

  20. Application for Presidential Permit OE Docket No. PP-371 Northern Pass

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Transmission: Comments from Lee Ann Moulder | Department of Energy Lee Ann Moulder Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Lee Ann Moulder Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border. LeeAnnMoulder_PP-371Comments.pdf (17.16 KB) More Documents & Publications Application for Presidential Permit OE Docket No. PP-371 Northern Pass

  1. Application for Presidential Permit OE Docket No. PP-371 Northern Pass

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Transmission: Comments from Michael Marino | Department of Energy Michael Marino Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Michael Marino Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border. MichaelMarino_PP-371Comments.pdf (17.51 KB) More Documents & Publications Application for Presidential Permit OE Docket No. PP-371 Northern Pass

  2. Application for Presidential Permit OE Docket No. PP-371 Northern Pass

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Transmission: Comments from Pamela Martin | Department of Energy Pamela Martin Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Pamela Martin Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border. PamelaMartin_PP-371Comments.pdf (20.58 KB) More Documents & Publications Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission:

  3. Consider Installing Turbulators on Two- and Three-Pass Firetube Boilers |

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Department of Energy Turbulators on Two- and Three-Pass Firetube Boilers Consider Installing Turbulators on Two- and Three-Pass Firetube Boilers This tip sheet outlines the benefits of turbulators on firetube boilers as part of optimized steam systems. STEAM TIP SHEET #25 Consider Installing Turbulators on Two- and Three-Pass Firetube Boilers (January 2012) (373.54 KB) More Documents & Publications Clean Boiler Waterside Heat Transfer Surfaces CIBO Energy Efficiency Handbook Reverse

  4. GaTe semiconductor for radiation detection

    DOE Patents [OSTI]

    Payne, Stephen A.; Burger, Arnold; Mandal, Krishna C.

    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.

  5. 2-M Probe At Astor Pass Area (Kratt, Et Al., 2010) | Open Energy...

    Open Energy Information (Open El) [EERE & EIA]

    Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: 2-M Probe At Astor Pass Area (Kratt, Et Al., 2010) Exploration Activity Details Location...

  6. Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Roy Stever

    Energy.gov [DOE]

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada  Border.

  7. GaP ring-like nanostructures on GaAs (100) with In{sub 0.15}Ga{sub 0.85}As compensation layers

    SciTech Connect (OSTI)

    Prongjit, Patchareewan Pankaow, Naraporn Boonpeng, Poonyasiri Thainoi, Supachok Panyakeow, Somsak Ratanathammaphan, Somchai

    2013-12-04

    We present the fabrication of GaP ring-like nanostructures on GaAs (100) substrates with inserted In{sub 0.15}Ga{sub 0.85}As compensation layers. The samples are grown by droplet epitaxy using solid-source molecular beam epitaxy. The dependency of nanostructural and optical properties of GaP nanostructures on In{sub 0.15}Ga{sub 0.85}As layer thickness is investigated by ex-situ atomic force microscope (AFM) and photoluminescence (PL). It is found that the characteristics of GaP ring-like structures on GaAs strongly depend on the In{sub 0.15}Ga{sub 0.85}As layer thickness.

  8. Proceedings of the 2002 U.S. DOE Hydrogen and Fuel Cells Annual Program/Lab R&D Review, May 6-10, 2002, Golden, Colorado.

    Energy.gov [DOE]

    Proceedings of the US DOE Hydrogen Program, the Fuel Cells for Transportation Program, and the Fuels for Fuel Cells Program inaugural combined Annual Program/Lab R&D Review held May 6-10, 2002 in Golden, Colorado.

  9. Financial Assistance Funding Opportunity Announcement: U.S. Department of Energy Energy Efficiency and Renewable Energy Golden Service Center

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    FINANCIAL ASSISTANCE FUNDING OPPORTUNITY ANNOUNCEMENT U.S. Department of Energy Energy Efficiency and Renewable Energy Golden Service Center Tribal Renewable Energy and Energy Efficiency Deployment Assistance Funding Opportunity Announcement Number: DE-FOA-0000853 Announcement Type: Amendment 002 CFDA Number: 81.087 Issue Date: April 30, 2013 Application Due Date: June 20, 2013, 5:00 PM Eastern Time Funding Opportunity Announcement Tribal Renewable Energy and Energy Efficiency Deployment

  10. Lattice-matched epitaxial GaInAsSb/GaSb thermophotovoltaic devices

    SciTech Connect (OSTI)

    Wang, C.A.; Choi, H.K.; Turner, G.W.; Spears, D.L.; Manfra, M.J.; Charache, G.W.

    1997-05-01

    The materials development of Ga{sub 1{minus}x}In{sub x}As{sub y}Sb{sub 1{minus}y} alloys for lattice-matched thermophotovoltaic (TPV) devices is reported. Epilayers with cutoff wavelength 2--2.4 {micro}m at room temperature and lattice-matched to GaSb substrates were grown by both low-pressure organometallic vapor phase epitaxy and molecular beam epitaxy. These layers exhibit high optical and structural quality. For demonstrating lattice-matched thermophotovoltaic devices, p- and n-type doping studies were performed. Several TPV device structures were investigated, with variations in the base/emitter thicknesses and the incorporation of a high bandgap GaSb or AlGaAsSb window layer. Significant improvement in the external quantum efficiency is observed for devices with an AlGaAsSb window layer compared to those without one.

  11. 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.

  12. Enhanced thermoelectric transport in modulation-doped GaN/AlGaN core/shell nanowires

    DOE PAGES-Beta [OSTI]

    Song, Erdong; Li, Qiming; Swartzentruber, Brian; Pan, Wei; Wang, George T.; Martinez, Julio A.

    2015-11-25

    The thermoelectric properties of unintentionally n-doped core GaN/AlGaN core/shell N-face nanowires are reported. We found that the temperature dependence of the electrical conductivity is consistent with thermally activated carriers with two distinctive donor energies. The Seebeck coefficient of GaN/AlGaN nanowires is more than twice as large as that for the GaN nanowires alone. However, an outer layer of GaN deposited onto the GaN/AlGaN core/shell nanowires decreases the Seebeck coefficient at room temperature, while the temperature dependence of the electrical conductivity remains the same. We attribute these observations to the formation of an electron gas channel within the heavily-doped GaN coremore » of the GaN/AlGaN nanowires. The room-temperature thermoelectric power factor for the GaN/AlGaN nanowires can be four times higher than the GaN nanowires. As a result, selective doping in bandgap engineered core/shell nanowires is proposed for enhancing the thermoelectric power.« less

  13. Enhanced thermoelectric transport in modulation-doped GaN/AlGaN core/shell nanowires

    SciTech Connect (OSTI)

    Song, Erdong; Li, Qiming; Swartzentruber, Brian; Pan, Wei; Wang, George T.; Martinez, Julio A.

    2015-11-25

    The thermoelectric properties of unintentionally n-doped core GaN/AlGaN core/shell N-face nanowires are reported. We found that the temperature dependence of the electrical conductivity is consistent with thermally activated carriers with two distinctive donor energies. The Seebeck coefficient of GaN/AlGaN nanowires is more than twice as large as that for the GaN nanowires alone. However, an outer layer of GaN deposited onto the GaN/AlGaN core/shell nanowires decreases the Seebeck coefficient at room temperature, while the temperature dependence of the electrical conductivity remains the same. We attribute these observations to the formation of an electron gas channel within the heavily-doped GaN core of the GaN/AlGaN nanowires. The room-temperature thermoelectric power factor for the GaN/AlGaN nanowires can be four times higher than the GaN nanowires. As a result, selective doping in bandgap engineered core/shell nanowires is proposed for enhancing the thermoelectric power.

  14. Application for Presidential Permit OE Docket No. PP-371 Northern Pass

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Transmission: Comments from Nancy Rheinhardt | Department of Energy Nancy Rheinhardt Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Nancy Rheinhardt Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border. Nancy_Rheinhardt_Comments.pdf (43.36

  15. SEMI-ANNUAL REPORTS FOR SABINE PASS LIQUEFACTION, LLC - FE DKT...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    SABINE PASS LIQUEFACTION, LLC - FE DKT. NO. 10-85-LNG; 10-111-LNG; 13-121-LNG; 14-31-LNG; 13-30-LNG; 13-42-LNG; 14-92-LNG SEMI-ANNUAL REPORTS FOR SABINE PASS LIQUEFACTION, LLC - FE ...

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

    SciTech Connect (OSTI)

    Krishnamoorthy, Sriram E-mail: rajan@ece.osu.edu; Akyol, Fatih; Rajan, Siddharth E-mail: rajan@ece.osu.edu

    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} Ω 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} Ω 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.

  17. 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.; Hofling, S.; Worschech, L.; Grutzmacher, 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, μ-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.

  18. Structural and optical properties of InGaN--GaN nanowire heterostructures grown by molecular beam epitaxy

    DOE PAGES-Beta [OSTI]

    Limbach, F.; Gotschke, T.; Stoica, T.; Calarco, R.; Sutter, E.; Ciston, J.; Cusco, R.; Artus, L.; Kremling, S.; Hofling, 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, μ-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

  19. Structural and optical properties of InGaNGaN nanowire heterostructures grown by molecular beam epitaxy

    DOE PAGES-Beta [OSTI]

    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 GaNmoreto 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

  20. Investigation of surface-plasmon coupled red light emitting InGaN/GaN multi-quantum well with Ag nanostructures coated on GaN surface

    SciTech Connect (OSTI)

    Li, Yi; Liu, Bin E-mail: rzhang@nju.edu.cn; Zhang, Rong E-mail: rzhang@nju.edu.cn; Xie, Zili; Zhuang, Zhe; Dai, JiangPing; Tao, Tao; Zhi, Ting; Zhang, Guogang; Chen, Peng; Ren, Fangfang; Zhao, Hong; Zheng, Youdou

    2015-04-21

    Surface-plasmon (SP) coupled red light emitting InGaN/GaN multiple quantum well (MQW) structure is fabricated and investigated. The centre wavelength of 5-period InGaN/GaN MQW structure is about 620?nm. The intensity of photoluminescence (PL) for InGaN QW with naked Ag nano-structures (NS) is only slightly increased due to the oxidation of Ag NS as compared to that for the InGaN QW. However, InGaN QW with Ag NS/SiO{sub 2} structure can evidently enhance the emission efficiency due to the elimination of surface oxide layer of Ag NS. With increasing the laser excitation power, the PL intensity is enhanced by 25%53% as compared to that for the SiO{sub 2} coating InGaN QW. The steady-state electric field distribution obtained by the three-dimensional finite-difference time-domain method is different for both structures. The proportion of the field distributed in the Ag NS for the GaN/Ag NS/SiO{sub 2} structure is smaller as compared to that for the GaN/naked Ag NS structure. As a result, the energy loss of localized SP modes for the GaN/naked Ag NS structure will be larger due to the absorption of Ag layer.

  1. Strain-compensated (Ga,In)N/(Al,Ga)N/GaN multiple quantum wells for improved yellow/amber light emission

    SciTech Connect (OSTI)

    Lekhal, K.; Damilano, B. De Mierry, P.; Venngus, P.; Ngo, H. T.; Rosales, D.; Gil, B.; Hussain, S.

    2015-04-06

    Yellow/amber (570600?nm) emitting In{sub x}Ga{sub 1?x}N/Al{sub y}Ga{sub 1?y}N/GaN multiple quantum wells (QWs) have been grown by metal organic chemical vapor deposition on GaN-on- sapphire templates. When the (Al,Ga)N thickness of the barrier increases, the room temperature photoluminescence is red-shifted while its yield increases. This is attributed to an increase of the QW internal electric field and an improvement of the material quality due to the compensation of the compressive strain of the In{sub x}Ga{sub 1?x}N QWs by the Al{sub y}Ga{sub 1?y}N layers, respectively.

  2. On strongly GA-convex functions and stochastic processes

    SciTech Connect (OSTI)

    Bekar, Nurgl Okur; Akdemir, Hande Gnay; ??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.

  3. Notices of Availability (NOA) | Department of Energy

    Energy Savers

    Golden Pass LNG Export Project; Texas and Louisiana March 23, 2016 EIS-0501: Notice of Availability of Draft Environmental Impact Statement Golden Pass LNG Export Project; Texas ...

  4. Few-hole double quantum dot in an undoped GaAs/AlGaAs heterostructure

    SciTech Connect (OSTI)

    Tracy, L. A.; Hargett, T. W.; Reno, J. L.

    2014-03-24

    We demonstrate a hole double quantum dot in an undoped GaAs/AlGaAs heterostructure. The interdot coupling can be tuned over a wide range, from formation of a large single dot to two well-isolated quantum dots. Using charge sensing, we show the ability to completely empty the dot of holes and control the charge occupation in the few-hole regime. The device should allow for control of individual hole spins in single and double quantum dots in GaAs.

  5. 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.

  6. 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.

  7. 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.

  8. A Statement from U.S. Secretary of Energy Ernest Moniz on the Passing of

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    the First U.S. Secretary of Energy James Schlesinger | Department of Energy on the Passing of the First U.S. Secretary of Energy James Schlesinger A Statement from U.S. Secretary of Energy Ernest Moniz on the Passing of the First U.S. Secretary of Energy James Schlesinger March 27, 2014 - 5:58pm Addthis News Media Contact 202-586-4940 "The passing of Dr. James R. Schlesinger is a great loss for the academic, scientific and intelligence communities. It is a loss for the Department of

  9. Statement on the Passing of Admiral James D. Watkins | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    on the Passing of Admiral James D. Watkins Statement on the Passing of Admiral James D. Watkins July 30, 2012 - 2:03pm Addthis Secretary Chu Secretary Chu Former Secretary of Energy I learned with great sadness that a predecessor of mine at the Department of Energy, Admiral James Watkins, passed away late last week. Admiral Watkins was a dedicated public servant who served this Department and his country well. In addition to serving as Secretary of Energy under President George H.W. Bush from

  10. Survival Rates of Juvenile Salmonids Passing Through the Bonneville Dam and Spillway in 2008

    SciTech Connect (OSTI)

    Ploskey, Gene R.; Weiland, Mark A.; Faber, Derrek M.; Deng, Zhiqun; Johnson, Gary E.; Hughes, James S.; Zimmerman, Shon A.; Monter, Tyrell J.; Cushing, Aaron W.; Wilberding, Matthew C.; Durham, Robin E.; Townsend, R. L.; Skalski, J. R.; Buchanan, Rebecca A.; Kim, Jina; Fischer, Eric S.; Meyer, Matthew M.; McComas, Roy L.; Everett, Jason

    2009-12-28

    This report describes a 2008 acoustic telemetry survival study conducted by the Pacific Northwest National Laboratory for the Portland District of the U.S. Army Corps of Engineers. The study estimated the survival of juvenile Chinook salmon and steelhead passing Bonneville Dam (BON) and its spillway. Of particular interest was the relative survival of smolts detected passing through end spill bays 1-3 and 16-18, which had deep flow deflectors immediately downstream of spill gates, versus survival of smolts passing middle spill bays 4-15, which had shallow flow deflectors.

  11. GaAs photoconductive semiconductor switch

    DOE Patents [OSTI]

    Loubriel, G.M.; Baca, A.G.; Zutavern, F.J.

    1998-09-08

    A high gain, optically triggered, photoconductive semiconductor switch (PCSS) implemented in GaAs as a reverse-biased pin structure with a passivation layer above the intrinsic GaAs substrate in the gap between the two electrodes of the device is disclosed. The reverse-biased configuration in combination with the addition of the passivation layer greatly reduces surface current leakage that has been a problem for prior PCSS devices and enables employment of the much less expensive and more reliable DC charging systems instead of the pulsed charging systems that needed to be used with prior PCSS devices. 5 figs.

  12. GaAs photoconductive semiconductor switch

    DOE Patents [OSTI]

    Loubriel, Guillermo M.; Baca, Albert G.; Zutavern, Fred J.

    1998-01-01

    A high gain, optically triggered, photoconductive semiconductor switch (PCSS) implemented in GaAs as a reverse-biased pin structure with a passivation layer above the intrinsic GaAs substrate in the gap between the two electrodes of the device. The reverse-biased configuration in combination with the addition of the passivation layer greatly reduces surface current leakage that has been a problem for prior PCSS devices and enables employment of the much less expensive and more reliable DC charging systems instead of the pulsed charging systems that needed to be used with prior PCSS devices.

  13. GA-AL-SC | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    GA-AL-SC GA-AL-SC October 1, 2012 ALA-1-N Wholesale Power Rate Schedule Area: PowerSouth Energy Cooperative System: Georgia-Alabama-South Carolina October 1, 2012 Duke-1-E Wholesale Power Rate Schedule Area: Duke On-System System: Georgia-Alabama-South Carolina October 1, 2012 Duke-2-E Wholesale Power Rate Schedule Area: Central System: Georgia-Alabama-South Carolina October 1, 2012 Duke-3-E Wholesale Power Rate Schedule Area: None System: Georgia-Alabama-South Carolina October 1, 2012 Duke-4-E

  14. 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.

  15. Sitewide Environmental Assessment for the National Renewable Energy Laboratory, Golden, Colorado

    SciTech Connect (OSTI)

    Not Available

    1993-05-04

    The Solar Energy Research, Development, and Demonstration Act of 1974 authorized a federal program to develop solar energy as a viable source of the nation`s future energy needs. Under this authority, the National Renewable Energy Laboratory (NREL) was created as a laboratory of the Department of Energy (DOE) to research a number of renewable energy possibilities. The laboratory conducts its operations both in government-owned facilities on the NREL South Table Mountain (STM) Site near Golden, Colorado, and in a number of leased facilities, particularly the Denver West Office Park. NREL operations include research in energy technologies, and other areas of national environmental and energy technology interest. Examples of these technologies include electricity from sunlight with solar cells (photovoltaics); energy from wind (windmills or wind turbines); conversion of plants and plant products (biomass) into liquid fuels (ethanol and methanol); heat from the sun (solar thermal) in place of wood, oil, gas, coal and other forms of heating; and solar buildings. NREL proposes to continue and expand the present R&D efforts in C&R energy by making infrastructure improvements and constructing facilities to eventually consolidate the R&D and associated support activities at its STM Site. In addition, it is proposed that operations continue in current leased space at the present levels of activity until site development is complete. The construction schedule proposed is designed to develop the site as rapidly as possible, dependent on Congressional funding, to accommodate not only the existing R&D that is being conducted in leased facilities off-site but to also allow for the 20-year projected growth. Impacts from operations currently conducted off-site are quantified and added to the cumulative impacts of the STM site. This environmental assessment provides information to determine the severity of impacts on the environment from the proposed action.

  16. Trap-assisted tunneling in aluminum-doped ZnO/indium oxynitride nanodot interlayer Ohmic contacts on p-GaN

    SciTech Connect (OSTI)

    Ke, Wen-Cheng Yang, Cheng-Yi; Lee, Fang-Wei; Chen, Wei-Kuo; Huang, Hao-Ping

    2015-10-21

    This study developed an Ohmic contact formation method for a ZnO:Al (AZO) transparent conductive layer on p-GaN films involving the introduction of an indium oxynitride (InON) nanodot interlayer. An antisurfactant pretreatment was used to grow InON nanodots on p-GaN films in a RF magnetron sputtering system. A low specific contact resistance of 1.12 × 10{sup −4} Ω cm{sup 2} was achieved for a sample annealed at 500 °C for 30 s in nitrogen ambient and embedded with an InON nanodot interlayer with a nanodot density of 6.5 × 10{sup 8} cm{sup −2}. By contrast, a sample annealed in oxygen ambient exhibited non-Ohmic behavior. X-ray photoemission spectroscopy results showed that the oxygen vacancy (V{sub o}) in the InON nanodots played a crucial role in carrier transport. The fitting I–V characteristic curves indicated that the hopping mechanism with an activation energy of 31.6 meV and trap site spacing of 1.1 nm dominated the carrier transport in the AZO/InON nanodot/p-GaN sample. Because of the high density of donor-like oxygen vacancy defects at the InON nanodot/p-GaN interface, positive charges from the underlying p-GaN films were absorbed at the interface. This led to positive charge accumulation, creating a narrow depletion layer; therefore, carriers from the AZO layer passed through InON nanodots by hopping transport, and subsequently tunneling through the interface to enter the p-GaN films. Thus, AZO Ohmic contact can be formed on p-GaN films by embedding an InON nanodot interlayer to facilitate trap-assisted tunneling.

  17. First results of electron temperature measurements by the use of multi-pass Thomson scattering system in GAMMA 10

    SciTech Connect (OSTI)

    Yoshikawa, M., E-mail: yosikawa@prc.tsukuba.ac.jp; Nagasu, K.; Shimamura, Y.; Shima, Y.; Kohagura, J.; Sakamoto, M.; Nakashima, Y.; Imai, T.; Ichimura, M. [Plasma Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 (Japan); Yasuhara, R.; Yamada, I.; Funaba, H.; Kawahata, K. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki, Gifu 509-5292 (Japan); Minami, T. [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)

    2014-11-15

    A multi-pass Thomson scattering (TS) has the advantage of enhancing scattered signals. We constructed a multi-pass TS system for a polarisation-based system and an image relaying system modelled on the GAMMA 10 TS system. We undertook Raman scattering experiments both for the multi-pass setting and for checking the optical components. Moreover, we applied the system to the electron temperature measurements in the GAMMA 10 plasma for the first time. The integrated scattering signal was magnified by approximately three times by using the multi-pass TS system with four passes. The electron temperature measurement accuracy is improved by using this multi-pass system.

  18. 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.

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

    SciTech Connect (OSTI)

    Bocquel, J.; Koenraad, P. M.; Giddings, A. D.; Prosa, T. J.; Larson, D. J.; Mano, T.

    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.

  20. 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.; Lth, 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.

  1. Application for presidential permit OE Docket No. PP-371 Northern Pass Transmission LLC: Addendum to Application

    Office of Energy Efficiency and Renewable Energy (EERE)

    On October 14, 2010, Northern Pass Transmission, LLC submitted an application for a Presidential Permit to construct a 1,200 MW high voltage direct current ("HVDC") transmission line (the ...

  2. Venture Global Calcasieu Pass, LLC- FE Dkt. No.- 15-25-LNG

    Energy.gov [DOE]

    The Office of Fossil Energy gives notice of receipt of an Application filed February 9, 2015, by Venture Global Calcasieu Pass, LLC (Venture Global), seeking a long-term multi-contract...

  3. SEMI-ANNUAL REPORTS FOR SABINE PASS LIQUEFACTION, LLC - FE DKT...

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    3-131-LNG - ORDER 3384 SEMI-ANNUAL REPORTS FOR SABINE PASS LIQUEFACTION, LLC - FE DKT. NO. 13-131-LNG - ORDER 3384 April 2014 (6.21 MB) More Documents & Publications SEMI-ANNUAL ...

  4. SEMI-ANNUAL REPORTS FOR VENTURE GLOBAL CALCASIEU PASS, LLC (formerly...

    Energy.gov (indexed) [DOE]

    2016 (36.2 KB) More Documents & Publications EIS-0510: Supplemental Notice of Intent Venture Global Calcasieu Pass, LLC - FE Dkt. No. - 15-25-LNG EIS-0501: FERC Project Update

  5. Sabine Pass Liquefaction, LLC – FE Dkt. No. 14-92-LNG

    Energy.gov [DOE]

    The Office of Fossil Energy gives notice of receipt of an Application filed on July 11, 2014, by Sabine Pass Liquefaction, LLC (SPL), seeking long-term multi-contract authorization to export...

  6. Passing particle toroidal precession induced by electric field in a tokamak

    SciTech Connect (OSTI)

    Andreev, V. V.; Ilgisonis, V. I.; Sorokina, E. A.; NRC “Kurchatov Institute”, Kurchatov Sq. 1, Moscow 123182

    2013-12-15

    Characteristics of a rotation of passing particles in a tokamak with radial electric field are calculated. The expression for time-averaged toroidal velocity of the passing particle induced by the electric field is derived. The electric-field-induced additive to the toroidal velocity of the passing particle appears to be much smaller than the velocity of the electric drift calculated for the poloidal magnetic field typical for the trapped particle. This quantity can even have the different sign depending on the azimuthal position of the particle starting point. The unified approach for the calculation of the bounce period and of the time-averaged toroidal velocity of both trapped and passing particles in the whole volume of plasma column is presented. The results are obtained analytically and are confirmed by 3D numerical calculations of the trajectories of charged particles.

  7. High peak-power kilohertz laser system employing single-stage multi-pass amplification

    DOE Patents [OSTI]

    Shan, Bing; Wang, Chun; Chang, Zenghu

    2006-05-23

    The present invention describes a technique for achieving high peak power output in a laser employing single-stage, multi-pass amplification. High gain is achieved by employing a very small "seed" beam diameter in gain medium, and maintaining the small beam diameter for multiple high-gain pre-amplification passes through a pumped gain medium, then leading the beam out of the amplifier cavity, changing the beam diameter and sending it back to the amplifier cavity for additional, high-power amplification passes through the gain medium. In these power amplification passes, the beam diameter in gain medium is increased and carefully matched to the pump laser's beam diameter for high efficiency extraction of energy from the pumped gain medium. A method of "grooming" the beam by means of a far-field spatial filter in the process of changing the beam size within the single-stage amplifier is also described.

  8. Regional Comparisons, Spatial Aggregation, and Asymmetry of Price Pass-Through

    Reports and Publications

    2005-01-01

    Spot to retail price pass-through behavior of the U.S. gasoline market was investigated at the national and regional levels, using weekly wholesale and retail motor gasoline prices from January 2000 to the present.

  9. Application for Presidential permit OE Docket No. PP-371 Northern Pass

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Transmission: Comments and Requests for Intervention Received on the Amended Application | Department of Energy permit OE Docket No. PP-371 Northern Pass Transmission: Comments and Requests for Intervention Received on the Amended Application Application for Presidential permit OE Docket No. PP-371 Northern Pass Transmission: Comments and Requests for Intervention Received on the Amended Application PP-371 Comments from Lee Ann Moulder 08/25/13 Comments from Pamela Martin 08/25/13 Comments

  10. Application for presidential permit OE Docket No. PP-371 Northern Pass

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Transmission LLC: Federal Register Notice Volume 75, No. 220 - Nov. 16, 2010 | Department of Energy LLC: Federal Register Notice Volume 75, No. 220 - Nov. 16, 2010 Application for presidential permit OE Docket No. PP-371 Northern Pass Transmission LLC: Federal Register Notice Volume 75, No. 220 - Nov. 16, 2010 Application from Northern Pass Transmission LLC to construct, operate, and maintain electric transmission facilities at the U.S-Canada border.. Federal Register Notice Vol 75 No 220.

  11. FINDING OF NO SIGNIFICANT IMPACT FOR SABINE PASS LIQUEFACTION PROJECT REGARDING

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    SABINE PASS LIQUEFACTION PROJECT REGARDING APPLICATION TO DEPARTMENT OF ENERGY TO INCREASE AUTHORIZED VOLUMES OF LIQUEFIED NATURAL GAS FOR EXPORT FROM SABINE PASS LNG TERMINAL TO NON-FREE TRADE AGREEMENT NATIONS AGENCY: U.S. Department of Energy, Office of Fossil Energy ACTION: Finding of No Significant Impact SUMMARY: Pursuant to section 1508.9 of the regulations of the Council on Environmental Quality (CEQ), 40 CFR 1508.9, the Federal Energy Regulatory Commission (FERC) prepared an

  12. Optics correction for the multi-pass FFAG ERL machine eRHIC

    SciTech Connect (OSTI)

    Liu, C.; Brooks, S.; Litvinenko, V.; Minty, M.; Ptitsyn, V.; Trbojevic, D.

    2015-05-03

    Gradient errors in the multi-pass Fixed Field Alternating Gradient (FFAG) Energy Recovery Linac (ERL) machine, eRHIC, distort the beam orbit and therefore cause emittance increase. The localization and correction of gradient errors are essential for an effective orbit correction and emittance preservation. In this report, the methodology and simulation of optics correction for the multi-pass FFAG ERL machine eRHIC will be presented.

  13. 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.

  14. 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.

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

    SciTech Connect (OSTI)

    Hajłasz, M.; Donkers, J. J. T. M.; Sque, S. J.; Heil, S. B. S.; Gravesteijn, D. J.; Rietveld, F. J. R.; Schmitz, J.

    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.

  16. On-sun concentrator performance of GaInP/GaAs tandem cells

    SciTech Connect (OSTI)

    Friedman, D.J.; Kurtz, S.R.; Sinha, K.; McMahon, W.E.; Olson, J.M.

    1996-05-01

    The GaInP/GaAs concentrator device has been adapted for and tested in a prototype {open_quotes}real-world{close_quotes} concentrator power system. The device achieved an on-sun efficiency of 28% {+-} 1% in the range of approximately 200-260 suns with device operating temperatures of 38{degrees}C to 42{degrees}C. The authors discuss ways of further improving this performance for future devices.

  17. 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.

  18. Linear Fixed-Field Multi-Pass Arcs for Recirculating Linear Accelerators

    SciTech Connect (OSTI)

    V.S. Morozov, S.A. Bogacz, Y.R. Roblin, K.B. Beard

    2012-06-01

    Recirculating Linear Accelerators (RLA's) provide a compact and efficient way of accelerating particle beams to medium and high energies by reusing the same linac for multiple passes. In the conventional scheme, after each pass, the different energy beams coming out of the linac are separated and directed into appropriate arcs for recirculation, with each pass requiring a separate fixed-energy arc. In this paper we present a concept of an RLA return arc based on linear combined-function magnets, in which two and potentially more consecutive passes with very different energies are transported through the same string of magnets. By adjusting the dipole and quadrupole components of the constituting linear combined-function magnets, the arc is designed to be achromatic and to have zero initial and final reference orbit offsets for all transported beam energies. We demonstrate the concept by developing a design for a droplet-shaped return arc for a dog-bone RLA capable of transporting two beam passes with momenta different by a factor of two. We present the results of tracking simulations of the two passes and lay out the path to end-to-end design and simulation of a complete dog-bone RLA.

  19. JEMMRLA - Electron Model of a Muon RLA with Multi-pass Arcs

    SciTech Connect (OSTI)

    Bogacz, Slawomir Alex; Krafft, Geoffrey A.; Morozov, Vasiliy S.; Roblin, Yves R.

    2013-06-01

    We propose a demonstration experiment for a new concept of a 'dogbone' RLA with multi-pass return arcs -- JEMMRLA (Jlab Electron Model of Muon RLA). Such an RLA with linear-field multi-pass arcs was introduced for rapid acceleration of muons for the next generation of Muon Facilities. It allows for efficient use of expensive RF while the multi-pass arc design based on linear combined-function magnets exhibits a number of advantages over separate-arc or pulsed-arc designs. Here we describe a test of this concept by scaling a GeV scale muon design for electrons. Scaling muon momenta by the muon-to-electron mass ratio leads to a scheme, in which a 4.5 MeV electron beam is injected in the middle of a 3 MeV/pass linac with two double-pass return arcs and is accelerated to 18 MeV in 4.5 passes. All spatial dimensions including the orbit distortion are scaled by a factor of 7.5, which arises from scaling the 200 MHz muon RF to a readily available 1.5 GHz. The hardware requirements are not very demanding making it straightforward to implement. Such an RLA may have applications going beyond muon acceleration: in medical isotope production, radiation cancer therapy and homeland security.

  20. 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.

  1. 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.

  2. Hybrid type-I InAs/GaAs and type-II GaSb/GaAs quantum dot structure with enhanced photoluminescence

    SciTech Connect (OSTI)

    Ji, Hai-Ming; Liang, Baolai Simmonds, Paul J.; Juang, Bor-Chau; Yang, Tao; Young, Robert J.; Huffaker, Diana L.

    2015-03-09

    We investigate the photoluminescence (PL) properties of a hybrid type-I InAs/GaAs and type-II GaSb/GaAs quantum dot (QD) structure grown in a GaAs matrix by molecular beam epitaxy. This hybrid QD structure exhibits more intense PL with a broader spectral range, compared with control samples that contain only InAs or GaSb QDs. This enhanced PL performance is attributed to additional electron and hole injection from the type-I InAs QDs into the adjacent type-II GaSb QDs. We confirm this mechanism using time-resolved and power-dependent PL. These hybrid QD structures show potential for high efficiency QD solar cell applications.

  3. Reactive codoping of GaAlInP compound semiconductors

    DOE Patents [OSTI]

    Hanna, Mark Cooper; Reedy, Robert

    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.

  4. 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.; Ars, 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.

  5. Technical Feasibility Assessment of LED Roadway Lighting on the Golden Gate Bridge

    SciTech Connect (OSTI)

    Tuenge, Jason R.

    2012-09-01

    Subsequent to preliminary investigations by the Golden Gate Bridge Highway & Transportation District (GGB), in coordination with Pacific Gas & Electric (PG&E), the GATEWAY Demonstration program was asked to evaluate the technical feasibility of replacing existing roadway lighting on the bridge with products utilizing LED technology. GGB and PG&E also indicated interest in induction (i.e., electrodeless fluorescent) technology, since both light source types feature rated lifetimes significantly exceeding those of the existing high-pressure sodium (HPS) and low-pressure sodium (LPS) products. The goal of the study was to identify any solutions which would reduce energy use and maintenance without compromising the quantity or quality of existing illumination. Products used for roadway lighting on the historic bridge must be installed within the existing amber-lensed shoebox-style luminaire housings. It was determined that induction technology does not appear to represent a viable alternative for the roadway luminaires in this application; any energy savings would be attributable to a reduction in light levels. Although no suitable LED retrofit kits were identified for installation within existing luminaire housings, several complete LED luminaires were found to offer energy savings of 6-18%, suggesting custom LED retrofit kits could be developed to match or exceed the performance of the existing shoeboxes. Luminaires utilizing ceramic metal halide (CMH) were also evaluated, and some were found to offer 28% energy savings, but these products might actually increase maintenance due to the shorter rated lamp life. Plasma technology was evaluated, as well, but no suitable products were identified. Analysis provided in this report was completed in May 2012. Although LED technologies are expected to become increasingly viable over time, and product mock-ups may reveal near-term solutions, some options not currently considered by GGB may ultimately merit evaluation. For

  6. Development of Highly-Efficient GaInP/Si Tandem Solar Cells ...

    Office of Scientific and Technical Information (OSTI)

    Research Org: NREL (National Renewable Energy Laboratory (NREL), Golden, CO (United States)) Sponsoring Org: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar ...

  7. Study of the effects of GaN buffer layer quality on the dc characteristics of AlGaN/GaN high electron mobility transistors

    DOE PAGES-Beta [OSTI]

    Ahn, Shihyun; Zhu, Weidi; Dong, Chen; Le, Lingcong; Hwang, Ya-Hsi; Kim, Byung-Jae; Ren, Fan; Pearton, Stephen J.; Lind, Aaron G.; Jones, Kevin S.; et al

    2015-04-21

    Here we studied the effect of buffer layer quality on dc characteristics of AlGaN/GaN high electron mobility (HEMTs). AlGaN/GaN HEMT structures with 2 and 5 μm GaN buffer layers on sapphire substrates from two different vendors with the same Al concentration of AlGaN were used. The defect densities of HEMT structures with 2 and 5 μm GaN buffer layer were 7 × 109 and 5 × 108 cm₋2, respectively, as measured by transmission electron microscopy. There was little difference in drain saturation current or in transfer characteristics in HEMTs on these two types of buffer. However, there was no dispersionmore » observed on the nonpassivated HEMTs with 5 μm GaN buffer layer for gate-lag pulsed measurement at 100 kHz, which was in sharp contrast to the 71% drain current reduction for the HEMT with 2 μm GaN buffer layer.« less

  8. Study of the effects of GaN buffer layer quality on the dc characteristics of AlGaN/GaN high electron mobility transistors

    SciTech Connect (OSTI)

    Ahn, Shihyun; Zhu, Weidi; Dong, Chen; Le, Lingcong; Hwang, Ya-Hsi; Kim, Byung-Jae; Ren, Fan; Pearton, Stephen J.; Lind, Aaron G.; Jones, Kevin S.; Kravchenko, I. I.; Zhang, Ming-Lan

    2015-04-21

    Here we studied the effect of buffer layer quality on dc characteristics of AlGaN/GaN high electron mobility (HEMTs). AlGaN/GaN HEMT structures with 2 and 5 μm GaN buffer layers on sapphire substrates from two different vendors with the same Al concentration of AlGaN were used. The defect densities of HEMT structures with 2 and 5 μm GaN buffer layer were 7 × 109 and 5 × 108 cm₋2, respectively, as measured by transmission electron microscopy. There was little difference in drain saturation current or in transfer characteristics in HEMTs on these two types of buffer. However, there was no dispersion observed on the nonpassivated HEMTs with 5 μm GaN buffer layer for gate-lag pulsed measurement at 100 kHz, which was in sharp contrast to the 71% drain current reduction for the HEMT with 2 μm GaN buffer layer.

  9. Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from City of Concord- James Kennedy

    Energy.gov [DOE]

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  10. Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from State Senator Jeanie Forrester

    Office of Energy Efficiency and Renewable Energy (EERE)

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  11. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from The Weeks Lancaster Trust

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S, - Canada Border.

  12. Application for Presidential Permit OE Docket No. PP-371 Northern Pass: Comments from Stephen Buzzell and Lelah Sullivan

    Energy.gov [DOE]

    Application from Northern Pass to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  13. Application for Presidential Permit OE Docket No: PP-371 Northern Pass Transmission: Comments from William and Michelle Shoemaker

    Energy.gov [DOE]

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  14. Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from Paula VandeWerken

    Energy.gov [DOE]

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  15. Application for Presidential Permit OE Docket No. PP-371 Northern Pass Transmission: Comments from National Park Service- Wendy Jannsen

    Energy.gov [DOE]

    Application from Northern Pass Transmission to construct, operate and maintain electric transmission facilities at the U.S. - Canada Border.

  16. Integrating AlGaN/GaN high electron mobility transistor with Si: A comparative study of integration schemes

    SciTech Connect (OSTI)

    Mohan, Nagaboopathy; Raghavan, Srinivasan; Manikant,; Soman, Rohith

    2015-10-07

    AlGaN/GaN high electron mobility transistor stacks deposited on a single growth platform are used to compare the most common transition, AlN to GaN, schemes used for integrating GaN with Si. The efficiency of these transitions based on linearly graded, step graded, interlayer, and superlattice schemes on dislocation density reduction, stress management, surface roughness, and eventually mobility of the 2D-gas are evaluated. In a 500 nm GaN probe layer deposited, all of these transitions result in total transmission electron microscopy measured dislocations densities of 1 to 3 × 10{sup 9}/cm{sup 2} and <1 nm surface roughness. The 2-D electron gas channels formed at an AlGaN-1 nm AlN/GaN interface deposited on this GaN probe layer all have mobilities of 1600–1900 cm{sup 2}/V s at a carrier concentration of 0.7–0.9 × 10{sup 13}/cm{sup 2}. Compressive stress and changes in composition in GaN rich regions of the AlN-GaN transition are the most effective at reducing dislocation density. Amongst all the transitions studied the step graded transition is the one that helps to implement this feature of GaN integration in the simplest and most consistent manner.

  17. 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.

  18. Analysis of defects in GaAsN grown by chemical beam epitaxy on high index GaAs substrates

    SciTech Connect (OSTI)

    Bouzazi, Boussairi; Kojima, Nobuaki; Ohshita, Yoshio; Yamaguchi, Masafumi

    2013-09-27

    The lattice defects in GaAsN grown by chemical beam epitaxy on GaAs 311B and GaAs 10A toward [110] were characterized and discussed by using deep level transient spectroscopy (DLTS) and on the basis of temperature dependence of the junction capacitances (C{sub J}). In one hand, GaAsN films grown on GaAs 311B and GaAs 10A showed n-type and p-type conductivities, respectively although the similar and simultaneous growth conditions. This result is indeed in contrast to the common known effect of N concentration on the type of conductivity, since the surface 311B showed a significant improvement in the incorporation of N. Furthermore, the temperature dependence of C{sub J} has shown that GaAs 311B limits the formation of N-H defects. In the other hand, the energy states in the forbidden gap of GaAsN were obtained. Six electron traps, E1 to E6, were observed in the DLTS spectrum of GaAsN grown on GaAs 311B, with apparent activation energies of 0.02, 0.14, 0.16, 0.33, 0.48, and 0.74 eV below the bottom edge of the conduction band, respectively. In addition, four hole traps, H1 to H4, were observed in the DLTS spectrum of GaAsN grown on GaAs 10A, with energy depths of 0.13, 0.20, 0.39, and 0.52 eV above the valence band maximum of the alloy, respectively. Hence, the surface morphology of the GaAs substrate was found to play a key factor role in clarifying the electrical properties of GaAsN grown by CBE.

  19. Hybrid: Passing

    Alternative Fuels and Advanced Vehicles Data Center

    During heavy accelerating or when additional power is needed, the gasoline engine and electric motor are both used to propel the vehicle. Additional power from the battery is used ...

  20. Refractive index of erbium doped GaN thin films

    SciTech Connect (OSTI)

    Alajlouni, S.; Sun, Z. Y.; Li, J.; Lin, J. Y.; Jiang, H. X.; Zavada, J. M.

    2014-08-25

    GaN is an excellent host for erbium (Er) to provide optical emission in the technologically important as well as eye-safe 1540 nm wavelength window. Er doped GaN (GaN:Er) epilayers were synthesized on c-plane sapphire substrates using metal organic chemical vapor deposition. By employing a pulsed growth scheme, the crystalline quality of GaN:Er epilayers was significantly improved over those obtained by conventional growth method of continuous flow of reaction precursors. X-ray diffraction rocking curve linewidths of less than 300 arc sec were achieved for the GaN (0002) diffraction peak, which is comparable to the typical results of undoped high quality GaN epilayers and represents a major improvement over previously reported results for GaN:Er. Spectroscopic ellipsometry was used to determine the refractive index of the GaN:Er epilayers in the 1540 nm wavelength window and a linear dependence on Er concentration was found. The observed refractive index increase with Er incorporation and the improved crystalline quality of the GaN:Er epilayers indicate that low loss GaN:Er optical waveguiding structures are feasible.

  1. Electron Model Of A Dogbone RLA With Multi-Pass Arcs

    SciTech Connect (OSTI)

    Beard, Kevin B.; Roblin, Yves R.; Morozov, Vasiliy; Bogacz, Slawomir Alex; Krafft, Geoffrey A.

    2012-09-01

    The design of a dogbone Recirculated Linear Accelerator, RLA, with linear-field multi-pass arcs was earlier developed [1] for accelerating muons in a Neutrino Factory and a Muon Collider. It allows for efficient use of expensive RF while the multi-pass arc design based on linear combined-function magnets exhibits a number of advantages over separate-arc or pulsed-arc designs. Such an RLA may have applications going beyond muon acceleration. This paper describes a possible straightforward test of this concept by scaling a GeV scale muon design for electrons. Scaling muon momenta by the muon-to-electron mass ratio leads to a scheme, in which a 4.5 MeV electron beam is injected at the middle of a 3 MeV/pass linac with two double-pass return arcs and is accelerated to 18 MeV in 4.5 passes. All spatial dimensions including the orbit distortion are scaled by a factor of 7.5, which arises from scaling the 200 MHz muon RF to the frequency readily available at CEBAF: 1.5 GHz. The footprint of a complete RLA fits in an area of 25 by 7 m. The scheme utilizes only fixed magnetic fields including injection and extraction. The hardware requirements are not very demanding, making it straightforward to implement

  2. 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.

  3. EA-2036: Sabine Pass Liquefaction Project (design optimization); Cameron Parish, Louisiana

    Energy.gov [DOE]

    In January 2014, the Federal Energy Regulatory Commission (FERC) issued an EA to analyze the potential environmental impacts associated with an application to amend FERC’s April 2012 authorization of the Sabine Pass Liquefaction Project in order to optimize its design and operation. In April 2015, Sabine Pass Liquefaction, LLC, and Sabine Pass LNG, L.P., applied to DOE’s Office of Fossil Energy (FE) seeking authorization to increase the amount of liquefied natural gas (LNG) to be exported from the facility above the level that FE authorized in August 2012. DOE adopted FERC’s EA for the optimization and issued a finding of no significant impact on March 11, 2016.

  4. A proposal for a user-level, message passing interface in a distributed memory environment

    SciTech Connect (OSTI)

    Dongarra, J.J. |; Hempel, R.; Hey, A.J.G.; Walker, D.W.

    1993-02-01

    This paper describes Message Passing Interface 1 (MPI1), a proposed library interface standard for supporting point-to-point message passing. The intended standard will be provided with Fortran 77 and C interfaces, and will form the basis of a standard high level communication environment featuring collective communication and data distribution transformations. The standard proposed here provides blocking, nonblocking, and synchronized message passing between pairs of processes, with message selectivity by source process and message type. Provision is made for noncontiguous messages. Context control provides a convenient means of avoiding message selectivity conflicts between different phases of an application. The ability to form and manipulate process groups permits task parallelism to be exploited, and is a useful abstraction in controlling certain types of collective communication.

  5. Ab initio study of Ga-GaN system: Transition from adsorbed metal atoms to a metal–semiconductor junction

    SciTech Connect (OSTI)

    Witczak, Przemysław; Kempisty, Pawel; Strak, Pawel

    2015-11-15

    Ab initio studies of a GaN(0001)-Ga system with various thicknesses of a metallic Ga layer were undertaken. The studied systems extend from a GaN(0001) surface with a fractional coverage of gallium atoms to a Ga-GaN metal–semiconductor (m–s) contact. Electronic properties of the system are simulated using density functional theory calculations for different doping of the bulk semiconductor. It is shown that during transition from a bare GaN(0001) surface to a m–s heterostructure, the Fermi level stays pinned at a Ga-broken bond highly dispersive surface state to Ga–Ga states at the m–s interface. Adsorption of gallium leads to an energy gain of about 4 eV for a clean GaN(0001) surface and the energy decreases to 3.2 eV for a thickly Ga-covered surface. The transition to the m–s interface is observed. For a thick Ga overlayer such interface corresponds to a Schottky contact with a barrier equal to 0.9 and 0.6 eV for n- and p-type, respectively. Bond polarization-related dipole layer occurring due to an electron transfer to the metal leads to a potential energy jump of 1.5 eV, independent on the semiconductor doping. Additionally high electron density in the Ga–Ga bond region leads to an energy barrier about 1.2 eV high and 4 Å wide. This feature may adversely affect the conductivity of the n-type m–s system.

  6. Distributed bragg reflector using AIGaN/GaN

    DOE Patents [OSTI]

    Waldrip, Karen E.; Lee, Stephen R.; Han, Jung

    2004-08-10

    A supported distributed Bragg reflector or superlattice structure formed from a substrate, a nucleation layer deposited on the substrate, and an interlayer deposited on the nucleation layer, followed by deposition of (Al,Ga,B)N layers or multiple pairs of (Al,Ga,B)N/(Al,Ga,B)N layers, where the interlayer is a material selected from AlN, Al.sub.x Ga.sub.1-x N, and AlBN with a thickness of approximately 20 to 1000 angstroms. The interlayer functions to reduce or eliminate the initial tensile growth stress, thereby reducing cracking in the structure. Multiple interlayers utilized in an AlGaN/GaN DBR structure can eliminate cracking and produce a structure with a reflectivity value greater than 0.99.

  7. Well devices with annulus check valve and hydraulic by-pass

    SciTech Connect (OSTI)

    Lawson, J.E.

    1984-05-22

    Hanger apparatus for suporting pipe in a well, the apparatus including both an annulus check valve, via which communication is established with the annulus between the suspended pipe and surrounding casing, and a pressure fluid by-pass, via which communication with a down-hole device such as a safety valve is established. Opening of the check valve and establishment of communication via the by-pass are accomplished by a simple stabbing operation with, e.g., a handling tool or a production upper body. Alternately, the check valve is opened by hydraulic pressure delivered via the production upper body.

  8. ,"Eagle Pass, TX Natural Gas Pipeline Exports to Mexico (MMcf)"

    U.S. Energy Information Administration (EIA) (indexed site)

    Eagle Pass, TX Natural Gas Pipeline Exports to Mexico (MMcf)" ,"Click worksheet name or tab at bottom for data" ,"Worksheet Name","Description","# Of Series","Frequency","Latest Data for" ,"Data 1","Eagle Pass, TX Natural Gas Pipeline Exports to Mexico (MMcf)",1,"Annual",2015 ,"Release Date:","10/31/2016" ,"Next Release Date:","11/30/2016" ,"Excel File

  9. Accountable Property Representatives List and Property Pass Signer List by Organization, April 1, 2016

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Accountable Property Representatives/Property Pass Authorization 4/1/2016 Employee Authorized Organization Phone APR Primary Property Pass Signer PETEET, LISA J. ALL ORGS (202) 287-5496 √ AGEE, PATTIE M. EM-40 (202) 586-9417 √ AMES, RUSSELL SC-32 (202) 586-1082 √ √ ANDERSON, SHELLEY EI-11 (202) 586-6196 √ ANDERSON, SUE EM-73 (301) 903-8368 √ √ ATKINSON-HYMAN, DEBRA PA-1 (202) 586-2461 √ √ AUGUSTYN, ANN HG-6 (202) 287-1528 √ BARLETT, DENNIS EE-3C (202) 586-0874 √ BARNES,

  10. Survival of Juvenile Chinook Salmon Passing the Bonneville Dam Spillway in 2007

    SciTech Connect (OSTI)

    Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Zimmerman, Shon A.; Durham, Robin E.; Fischer, Eric S.; Kim, Jina; Townsend, R. L.; Skalski, J. R.; Buchanan, Rebecca A.; McComas, Roy L.

    2008-12-01

    The U.S. Army Corps of Engineers Portland District (CENWP) funds numerous evaluations of fish passage and survival on the Columbia River. In 2007, the CENWP asked Pacific Northwest National Laboratory to conduct an acoustic telemetry study to estimate the survival of juvenile Chinook salmon passing the spillway at Bonneville Dam. This report documents the study results which are intended to be used to improve the conditions juvenile anadromous fish experience when passing through the dams that the Corps operates on the river.

  11. Price of Sabine Pass, LA Liquefied Natural Gas Exports to Kuwait (Dollars

    U.S. Energy Information Administration (EIA) (indexed site)

    per Thousand Cubic Feet) Kuwait (Dollars per Thousand Cubic Feet) Price of Sabine Pass, LA Liquefied Natural Gas Exports to Kuwait (Dollars per Thousand Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2016 3 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Price of Liquefied Natural Gas Exports by Point of Exit Sabine Pass,

  12. Sabine Pass, LA Exports to Japan Liquefied Natural Gas (Million Cubic Feet)

    U.S. Energy Information Administration (EIA) (indexed site)

    Japan Liquefied Natural Gas (Million Cubic Feet) Sabine Pass, LA Exports to Japan Liquefied Natural Gas (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2012 3,174 1,863 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Liquefied Natural Gas Exports by Point of Exit Sabine Pass, LA Liquefied Natural

  13. Sabine Pass, LA Exports to Korea Liquefied Natural Gas (Million Cubic Feet)

    U.S. Energy Information Administration (EIA) (indexed site)

    Korea Liquefied Natural Gas (Million Cubic Feet) Sabine Pass, LA Exports to Korea Liquefied Natural Gas (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2011 2,901 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Liquefied Natural Gas Exports by Point of Exit Sabine Pass, LA Liquefied Natural Gas Ex

  14. Sabine Pass, LA Exports to Portugal Liquefied Natural Gas (Million Cubic

    U.S. Energy Information Administration (EIA) (indexed site)

    Feet) Portugal Liquefied Natural Gas (Million Cubic Feet) Sabine Pass, LA Exports to Portugal Liquefied Natural Gas (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2012 2,618 2016 3,700 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Liquefied Natural Gas Exports by Point of Exit Sabine Pass, LA Liquefied Natural

  15. Sabine Pass, LA Exports to United kingdom Liquefied Natural Gas (Million

    U.S. Energy Information Administration (EIA) (indexed site)

    Cubic Feet) United kingdom Liquefied Natural Gas (Million Cubic Feet) Sabine Pass, LA Exports to United kingdom Liquefied Natural Gas (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2011 2,862 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Liquefied Natural Gas Exports by Point of Exit Sabine Pass, LA Liquefied

  16. Sabine Pass, LA Liquefied Natural Gas Exports to Argentina (Million Cubic

    U.S. Energy Information Administration (EIA) (indexed site)

    Feet) Argentina (Million Cubic Feet) Sabine Pass, LA Liquefied Natural Gas Exports to Argentina (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2016 6,310 8,161 2,802 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Liquefied Natural Gas Exports by Point of Exit Sabine Pass, LA Liquefied Natural Gas Exports To

  17. Sabine Pass, LA Liquefied Natural Gas Exports to Brazil (Million Cubic

    U.S. Energy Information Administration (EIA) (indexed site)

    Feet) Brazil (Million Cubic Feet) Sabine Pass, LA Liquefied Natural Gas Exports to Brazil (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2011 1,680 4,681 2,108 2016 3,284 3,270 4,075 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Liquefied Natural Gas Exports by Point of Exit Sabine Pass, LA Liquefied Natural Gas

  18. Sabine Pass, LA Liquefied Natural Gas Exports to Chile (Million Cubic Feet)

    U.S. Energy Information Administration (EIA) (indexed site)

    Chile (Million Cubic Feet) Sabine Pass, LA Liquefied Natural Gas Exports to Chile (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2011 2,910 2016 6,230 4,643 6,074 9,518 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Liquefied Natural Gas Exports by Point of Exit Sabine Pass, LA Liquefied Natural Gas Exports to Chile

  19. Sabine Pass, LA Liquefied Natural Gas Exports to India (Million Cubic Feet)

    U.S. Energy Information Administration (EIA) (indexed site)

    India (Million Cubic Feet) Sabine Pass, LA Liquefied Natural Gas Exports to India (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2011 3,477 3,072 2016 3,390 3,617 3,701 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Liquefied Natural Gas Exports by Point of Exit Sabine Pass, LA Liquefied Natural Gas Exports to India

  20. Sabine Pass, LA Liquefied Natural Gas Exports to Jordan (Million Cubic

    U.S. Energy Information Administration (EIA) (indexed site)

    Feet) Jordan (Million Cubic Feet) Sabine Pass, LA Liquefied Natural Gas Exports to Jordan (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2016 3,566 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Liquefied Natural Gas Exports by Point of Exit Sabine Pass, LA Liquefied Natural Gas Exports to Jordan

  1. Sabine Pass, LA Liquefied Natural Gas Exports to Kuwait (Million Cubic

    U.S. Energy Information Administration (EIA) (indexed site)

    Feet) Kuwait (Million Cubic Feet) Sabine Pass, LA Liquefied Natural Gas Exports to Kuwait (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2016 3,610 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Liquefied Natural Gas Exports by Point of Exit Sabine Pass, LA Liquefied Natural Gas Exports to Kuwait

  2. Sabine Pass, LA Liquefied Natural Gas Exports to Mexico (Million Cubic

    U.S. Energy Information Administration (EIA) (indexed site)

    Feet) Mexico (Million Cubic Feet) Sabine Pass, LA Liquefied Natural Gas Exports to Mexico (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2016 3,686 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Liquefied Natural Gas Exports by Point of Exit Sabine Pass, LA Liquefied Natural Gas Exports to Mexico

  3. Sabine Pass, LA Liquefied Natural Gas Exports to United Arab Emirates

    U.S. Energy Information Administration (EIA) (indexed site)

    (Million Cubic Feet) United Arab Emirates (Million Cubic Feet) Sabine Pass, LA Liquefied Natural Gas Exports to United Arab Emirates (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2016 3,391 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Liquefied Natural Gas Exports by Point of Exit Sabine Pass, LA Liquefied

  4. Sabine Pass, LA Natural Gas Liquefied Natural Gas Imports (Million Cubic

    U.S. Energy Information Administration (EIA) (indexed site)

    Feet) (Million Cubic Feet) Sabine Pass, LA Natural Gas Liquefied Natural Gas Imports (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2014 3,006 2,874 2015 6,079 2,832 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Liquefied Natural Gas Imports by Point of Entry Sabine Pass, LA, CA LNG Exports to All Countrie

  5. Sabine Pass, LA Natural Gas Liquefied Natural Gas Imports from Qatar

    U.S. Energy Information Administration (EIA) (indexed site)

    (Million Cubic Feet) Qatar (Million Cubic Feet) Sabine Pass, LA Natural Gas Liquefied Natural Gas Imports from Qatar (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2011 8,918 9,000 4,541 4,576 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Liquefied Natural Gas Imports by Point of Entry Sabine Pass, LA LNG Imports

  6. SEMI-ANNUAL REPORTS FOR SABINE PASS LIQUEFACTION, LLC - FE DKT. NO.

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    13-131-LNG - ORDER 3384 | Department of Energy 3-131-LNG - ORDER 3384 SEMI-ANNUAL REPORTS FOR SABINE PASS LIQUEFACTION, LLC - FE DKT. NO. 13-131-LNG - ORDER 3384 April 2014 (6.21 MB) More Documents & Publications SEMI-ANNUAL REPORTS FOR SABINE PASS LIQUEFACTION, LLC - FE DKT. NO. 10-85-LNG et al: SEMI-ANNUAL REPORTS FOR CHENIERE MARKETING, LLC AND CORPUS CHRISTI LIQUEFACTION, LLC (NFTA) - FE DKT. NO. 12-97-LNG - ORDER 3638 SEMI-ANNUAL REPORTS FOR CHENIERE MARKETING, LLC and CORPUS

  7. SEMI-ANNUAL REPORTS FOR VENTURE GLOBAL CALCASIEU PASS, LLC (formerly

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    Venture Global LNG, LLC) - DKT. NO. 13-69-LNG (ORD 3345); 14-88-LNG (Ord 3520); 15-25-LNG (Ord 3662) | Department of Energy VENTURE GLOBAL CALCASIEU PASS, LLC (formerly Venture Global LNG, LLC) - DKT. NO. 13-69-LNG (ORD 3345); 14-88-LNG (Ord 3520); 15-25-LNG (Ord 3662) SEMI-ANNUAL REPORTS FOR VENTURE GLOBAL CALCASIEU PASS, LLC (formerly Venture Global LNG, LLC) - DKT. NO. 13-69-LNG (ORD 3345); 14-88-LNG (Ord 3520); 15-25-LNG (Ord 3662) October 2014 (123.7 KB) April 2015 (143.13 KB) October

  8. 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%.

  9. Raman spectroscopy of InGaAs/GaAs nanoheterostructures δ-doped with Mn

    SciTech Connect (OSTI)

    Plankina, S. M.; Vikhrova, O. V.; Danilov, Yu. A.; Zvonkov, B. N.; Kalentyeva, I. L.; Nezhdanov, A. V.; Chunin, I. I.; Yunin, P. A.

    2015-01-15

    The results of complex studies of InGaAs/GaAs nanoheterostructures δ-doped with Mn are reported. The structures are grown by metal-organic vapor-phase epitaxy in combination with laser deposition. By confocal Raman spectroscopy, it is shown that the low-temperature δ-doped GaAs cap layers are of higher crystal quality compared to uniformly doped layers. Scattering of light in the coupled phonon-plasmon mode is observed. The appearance of this mode is conditioned by the diffusion of manganese from the δ-layer. The thickness of the cap layer is found to be d{sub c} ≈ 9–20 nm, optimal for attainment of the highest photoluminescence intensity of the quantum well and the highest layer concentration of holes by doping with manganese.

  10. Electrical compensation by Ga vacancies in Ga{sub 2}O{sub 3} thin films

    SciTech Connect (OSTI)

    Korhonen, E.; Tuomisto, F.; Gogova, D.; Wagner, G.; Baldini, M.; Galazka, Z.; Schewski, R.; Albrecht, M.

    2015-06-15

    The authors have applied positron annihilation spectroscopy to study the vacancy defects in undoped and Si-doped Ga{sub 2}O{sub 3} thin films. The results show that Ga vacancies are formed efficiently during metal-organic vapor phase epitaxy growth of Ga{sub 2}O{sub 3} thin films. Their concentrations are high enough to fully account for the electrical compensation of Si doping. This is in clear contrast to another n-type transparent semiconducting oxide In{sub 2}O{sub 3}, where recent results show that n-type conductivity is not limited by cation vacancies but by other intrinsic defects such as O{sub i}.

  11. 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; Wang, Jianfeng; Ren, Guoqiang; Xu, Ke

    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 IV 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.

  12. 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.

  13. 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.

  14. 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.

  15. The disintegration of GaSb/GaAs nanostructures upon capping

    SciTech Connect (OSTI)

    Martin, Andrew J.; Hwang, Jinyoung; Marquis, Emmanuelle A.; Smakman, Erwin; Saucer, Timothy W.; Rodriguez, Garrett V.; Hunter, Allen H.; Sih, Vanessa; Koenraad, Paul M.; Phillips, Jamie D.; Millunchick, Joanna

    2013-01-01

    Atom probe tomography and cross-sectional scanning tunneling microscopy show that GaSb/GaAs quantum dots disintegrate into ring-like clusters of islands upon capping. Band transition energies calculated using an 8-band k.p model of the capped dots with the observed dimensions are consistent with emission energies observed in photoluminescence data. These results emphasize the need for full three-dimensional characterization to develop an accurate understanding of the structure, and thus the optical properties, of buried quantum dots.

  16. Photoluminescence studies of individual and few GaSb/GaAs quantum rings

    SciTech Connect (OSTI)

    Young, M. P.; Woodhead, C. S.; Roberts, J.; Noori, Y. J.; Noble, M. T.; Krier, A.; Hayne, M.; Young, R. J.; Smakman, E. P.; Koenraad, P. M.

    2014-11-15

    We present optical studies of individual and few GaSb quantum rings embedded in a GaAs matrix. Contrary to expectation for type-II confinement, we measure rich spectra containing sharp lines. These lines originate from excitonic recombination and are observed to have resolution-limited full-width at half maximum of 200 ?eV. The detail provided by these measurements allows the characteristic type-II blueshift, observed with increasing excitation power, to be studied at the level of individual nanostructures. These findings are in agreement with hole-charging being the origin of the observed blueshift.

  17. Application of the ASME code in the design of the GA-4 and GA-9 casks

    SciTech Connect (OSTI)

    Mings, W.J. ); Koploy, M.A. )

    1992-01-01

    General Atomics (GA) is developing two spent fuel shipping casks for transport by legal weight truck (LWT). The casks are designed to the loading, environmental conditions and safety requirements defined in Title 10 of the Code of Federal Regulations, Part 71 (10CFR71). To ensure that all components of the cask meet the 10CFR71 rules, GA established structural design criteria for each component based on NRC Regulatory Guides and the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code). This paper discusses the criteria used for different cask components, how they were applied and the conservatism and safety margins built into the criteria and assumption.

  18. Application of the ASME code in the design of the GA-4 and GA-9 casks

    SciTech Connect (OSTI)

    Mings, W.J.; Koploy, M.A.

    1992-08-01

    General Atomics (GA) is developing two spent fuel shipping casks for transport by legal weight truck (LWT). The casks are designed to the loading, environmental conditions and safety requirements defined in Title 10 of the Code of Federal Regulations, Part 71 (10CFR71). To ensure that all components of the cask meet the 10CFR71 rules, GA established structural design criteria for each component based on NRC Regulatory Guides and the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code). This paper discusses the criteria used for different cask components, how they were applied and the conservatism and safety margins built into the criteria and assumption.

  19. 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.

  20. 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.

  1. fe0013961-GaTech | netl.doe.gov

    U.S. Department of Energy (DOE) all webpages (Extended Search)

    Performer Georgia Tech Research Corporation, Atlanta GA 30332 Background While earlier research focused on the properties of the hydrate mass per se (Sloan Jr and Koh 2007), ...

  2. Bismuth alloying properties in GaAs nanowires

    SciTech Connect (OSTI)

    Ding, Lu; Lu, Pengfei; Cao, Huawei; Cai, Ningning; Yu, Zhongyuan; Gao, Tao; Wang, Shumin

    2013-09-15

    First-principles calculations have been performed to investigate the structural, electronic and optical properties of bismuth alloying in GaAs nanowires. A typical model of Ga{sub 31}As{sub 31} nanowires is introduced for its reasonable band gap. The band gap of GaAs{sub 1−x}Bi{sub x} shrinks clearly with the increasing Bi concentration and the band edge shifts when spin–orbit coupling (SOC) is considered. The insertion of Bi atom leads to hybridization of Ga/As/Bi p states which contributes a lot around Fermi level. Scissor effect is involved. The optical properties are presented, including dielectric function, optical absorption spectra and reflectivity, which are also varied with the increasing of Bi concentrations. - Graphical abstract: Top view of Bi-doped GaAs nanowires. Ga, As, and Bi atoms are denoted with grey, purple and red balls, respectively. Display Omitted - Highlights: • A typical model of Ga{sub 31}As{sub 31} nanowires is introduced for its reasonable band gap. • The band gap of GaAs{sub 1−x}Bi{sub x} shrinks clearly with the increasing Bi concentration. • The band edge shifts when spin–orbit coupling (SOC) is considered. • The insertion of Bi atom leads to hybridization of Ga/As/Bi p states.

  3. Photoluminescence from GaAs nanodisks fabricated by using combination...

    Office of Scientific and Technical Information (OSTI)

    GaAs nanodisks fabricated by using combination of neutral beam etching and atomic hydrogen-assisted molecular beam epitaxy regrowth Citation Details In-Document Search Title:...

  4. 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.

  5. 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.

  6. 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.

  7. Reactive codoping of GaAlInP compound semiconductors (Patent...

    Office of Scientific and Technical Information (OSTI)

    Patent: Reactive codoping of GaAlInP compound semiconductors Citation Details In-Document Search Title: Reactive codoping of GaAlInP compound semiconductors A GaAlInP compound ...

  8. Growth and Band Offsets of Epitaxial Lanthanide Oxides on GaN...

    Office of Scientific and Technical Information (OSTI)

    M.T.T., 60 (6) (2012) 3 Jon Ihlefeld, Sandia National Laboratories Electronic Materials ... Undoped GaN Undoped AlGaN Doped AlGaN 2D Electron Gas Enhancement Mode (nominally ...

  9. Long-wavelength shift and enhanced room temperature photoluminescence efficiency in GaAsSb/InGaAs/GaAs-based heterostructures emitting in the spectral range of 1.01.2??m due to increased charge carrier's localization

    SciTech Connect (OSTI)

    Kryzhkov, D. I. Yablonsky, A. N.; Morozov, S. V.; Aleshkin, V. Ya.; Krasilnik, Z. F.; Zvonkov, B. N.; Vikhrova, O. V.

    2014-11-28

    In this work, a study of the photoluminescence (PL) temperature dependence in quantum well GaAs/GaAsSb and double quantum well InGaAs/GaAsSb/GaAs heterostructures grown by metalorganic chemical vapor deposition with different parameters of GaAsSb and InGaAs layers has been performed. It has been demonstrated that in double quantum well InGaAs/GaAsSb/GaAs heterostructures, a significant shift of the PL peak to a longer-wavelength region (up to 1.2??m) and a considerable reduction in the PL thermal quenching in comparison with GaAs/GaAsSb structures can be obtained due to better localization of charge carriers in the double quantum well. For InGaAs/GaAsSb/GaAs heterostructures, an additional channel of radiative recombination with participation of the excited energy states in the quantum well, competing with the main ground-state radiative transition, has been revealed.

  10. 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.

  11. Memorandum of Understanding (MOU) between DOE, Northern Pass and SE Group- August 12, 2011

    Energy.gov [DOE]

    The Department of Energy (DOE) has selected an integrated team of professionals from three environmental consulting firms to prepare the DOE Environmental Impact Statement (EIS) addressing the Northern Pass Presidential Permit application and signed a Memorandum of Understanding with the group.

  12. Amended Notice of Intent for the Northern Pass Transmission Line Project Published in the Federal Register

    Energy.gov [DOE]

    The Department of Energy announces its intent to modify the scope of the Northern Pass Transmission Line Project Environmental Impact Statement and to conduct additional public scoping meetings. The Federal Register Notice, which is now available for downloading, includes information on how to submit comments and participate in the additional public scoping meetings.

  13. Fuel-element failures in Hanford single-pass reactors 1944--1971

    SciTech Connect (OSTI)

    Gydesen, S.P.

    1993-07-01

    The primary objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation dose that individuals could have received as a result of emissions since 1944 from the US Department of Energy`s (DOE) Hanford Site near Richland, Washington. To estimate the doses, the staff of the Source Terms Task use operating information from historical documents to approximate the radioactive emissions. One source of radioactive emissions to the Columbia River came from leaks in the aluminum cladding of the uranium metal fuel elements in single-pass reactors. The purpose of this letter report is to provide photocopies of the documents that recorded these failures. The data from these documents will be used by the Source Terms Task to determine the contribution of single-pass reactor fuel-element failures to the radioactivity of the reactor effluent from 1944 through 1971. Each referenced fuel-element failure occurring in the Hanford single-pass reactors is addressed. The first recorded failure was in 1948, the last in 1970. No records of fuel-element failures were found in documents prior to 1948. Data on the approximately 2000 failures which occurred during the 28 years (1944--1971) of Hanford single-pass reactor operations are provided in this report.

  14. Transition radiation generated by a particle passing through the apex of a conducting cone

    SciTech Connect (OSTI)

    Kol'tsov, A. V. Serov, A. V.

    2009-12-15

    The spatial field distribution is determined for the transition radiation generated by a particle passing through the apex of a cone along its axis. Expressions for the angular distribution of the radiation intensity are obtained for apex angles between 0 and {pi}. Characteristics of transition radiation emitted into a 'funnel' and a dihedral angle are compared.

  15. Structural Controls of the Emerson Pass Geothermal System, Washoe County, Nevada

    SciTech Connect (OSTI)

    Anderson, Ryan B; Faulds, James E

    2012-09-30

    We have conducted a detailed geologic study to better characterize a blind geothermal system in Emerson Pass on the Pyramid Lake Paiute Tribe Reservation, western Nevada. A thermal anomaly was discovered in Emerson Pass by use of 2 m temperature surveys deployed within a structurally favorable setting and proximal to surface features indicative of geothermal activity. The anomaly lies at the western edge of a broad left step at the northeast end of Pyramid Lake between the north- to north-northeast-striking, west-dipping, Fox and Lake Range normal faults. The 2-m temperature surveys have defined a N-S elongate thermal anomaly that has a maximum recorded temperature of ~60°C and resides on a north- to north-northeaststriking fault. Travertine mounds, chalcedonic silica veins, and silica cemented Pleistocene lacustrine gravels in Emerson Pass indicate a robust geothermal system active at the surface in the recent past. Structural complexity and spatial heterogeneities of the strain and stress field have developed in the step-over region, but kinematic data suggest a WNW-trending (~280° azimuth) extension direction. The geothermal system is likely hosted in Emerson Pass as a result of enhanced permeability generated by the intersection of two oppositely dipping, southward terminating north- to north-northwest-striking (Fox Range fault) and northnortheast- striking faults.

  16. Low pressure differential discharge characteristics of saturated liquids passing through orifices

    SciTech Connect (OSTI)

    Rohloff, T.J.; Catton, I.

    1996-09-01

    An experimental investigation has been performed to determine the effect of variation in the length-to-diameter ratios on the discharge characteristics of saturated liquids passing through square edge orifices subjected to low pressure differentials. Experiments were performed to confirm reported results for sharp edge orifices and for round edge orifices with appreciable ratios of inlet corner radius to orifice diameter.

  17. Multiple pass and multiple layer friction stir welding and material enhancement processes

    DOE Patents [OSTI]

    Feng, Zhili [Knoxville, TN; David, Stan A. [Knoxville, TN; Frederick, David Alan [Harriman, TN

    2010-07-27

    Processes for friction stir welding, typically for comparatively thick plate materials using multiple passes and multiple layers of a friction stir welding tool. In some embodiments a first portion of a fabrication preform and a second portion of the fabrication preform are placed adjacent to each other to form a joint, and there may be a groove adjacent the joint. The joint is welded and then, where a groove exists, a filler may be disposed in the groove, and the seams between the filler and the first and second portions of the fabrication preform may be friction stir welded. In some embodiments two portions of a fabrication preform are abutted to form a joint, where the joint may, for example, be a lap joint, a bevel joint or a butt joint. In some embodiments a plurality of passes of a friction stir welding tool may be used, with some passes welding from one side of a fabrication preform and other passes welding from the other side of the fabrication preform.

  18. 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.

  19. Interfacial bonding and electronic structure of GaN/GaAs interface: A first-principles study

    SciTech Connect (OSTI)

    Cao, Ruyue; Zhang, Zhaofu; Wang, Changhong; Li, Haobo; Dong, Hong; Liu, Hui; Wang, Weichao; Xie, Xinjian

    2015-04-07

    Understanding of GaN interfacing with GaAs is crucial for GaN to be an effective interfacial layer between high-k oxides and III-V materials with the application in high-mobility metal-oxide-semiconductor field effect transistor (MOSFET) devices. Utilizing first principles calculations, here, we investigate the structural and electronic properties of the GaN/GaAs interface with respect to the interfacial nitrogen contents. The decrease of interfacial N contents leads to more Ga dangling bonds and As-As dimers. At the N-rich limit, the interface with N concentration of 87.5% shows the most stability. Furthermore, a strong band offsets dependence on the interfacial N concentration is also observed. The valance band offset of N7 with hybrid functional calculation is 0.51 eV. The electronic structure analysis shows that significant interface states exist in all the GaN/GaAs models with various N contents, which originate from the interfacial dangling bonds and some unsaturated Ga and N atoms. These large amounts of gap states result in Fermi level pinning and essentially degrade the device performance.

  20. SCALED ELECTRON MODEL OF A DOGBONE MUON RLA WITH MULTI-PASS ARCS

    SciTech Connect (OSTI)

    Kevin Beard, Rolland Johnson, Vasiliy Morozov, Yves Roblin, Andrew Hutton, Geoffrey Krafft, Slawomir Bogacz

    2012-07-01

    The design of a dogbone RLA with linear-field multi-pass arcs was earlier developed for accelerating muons in a Neutrino Factory and a Muon Collider. It allows for efficient use of expensive RF while the multi-pass arc design based on linear combined-function magnets exhibits a number of advantages over separate-arc or pulsed-arc designs. Such an RLA may have applications going beyond muon acceleration. This paper describes a possible straightforward test of this concept by scaling a GeV scale muon design for electrons. Scaling muon momenta by the muon-to-electron mass ratio leads to a scheme, in which a 4.5 MeV electron beam is injected at the middle of a 3 MeV/pass linac with two double-pass return arcs and is accelerated to 18 MeV in 4.5 passes. All spatial dimensions including the orbit distortion are scaled by a factor of 7.5, which arises from scaling the 200 MHz muon RF to a readily available at CEBAF 1.5 GHz. The footprint of a complete RLA fits in an area of 25 by 7 m. The scheme utilizes only fixed magnetic fields including injection and extraction. The hardware requirements are not very demanding, making it straightforward to implement. In this report, we have shown first of all that measuring the energy spectrum of the fast neutrons in the liquid scintillators allows one to distinguish the two chemical forms of plutonium. In addition, combining this information with the Feynman 2-neutron and 3-neutron correlations allows one to extract the {alpha}-ratio without explicitly knowing the multiplication. Given the {alpha}-ratio one can then extract the multiplication as well as the {sup 239}Pu and {sup 240}Pu masses directly from the moment equations.

  1. Self-catalyzed growth of dilute nitride GaAs/GaAsSbN/GaAs core-shell nanowires by molecular beam epitaxy

    SciTech Connect (OSTI)

    Kasanaboina, Pavan Kumar; Ahmad, Estiak; Li, Jia; Iyer, Shanthi; Reynolds, C. Lewis; Liu, Yang

    2015-09-07

    Bandgap tuning up to 1.3 μm in GaAsSb based nanowires by incorporation of dilute amount of N is reported. Highly vertical GaAs/GaAsSbN/GaAs core-shell configured nanowires were grown for different N contents on Si (111) substrates using plasma assisted molecular beam epitaxy. X-ray diffraction analysis revealed close lattice matching of GaAsSbN with GaAs. Micro-photoluminescence (μ-PL) revealed red shift as well as broadening of the spectra attesting to N incorporation in the nanowires. Replication of the 4K PL spectra for several different single nanowires compared to the corresponding nanowire array suggests good compositional homogeneity amongst the nanowires. A large red shift of the Raman spectrum and associated symmetric line shape in these nanowires have been attributed to phonon localization at point defects. Transmission electron microscopy reveals the dominance of stacking faults and twins in these nanowires. The lower strain present in these dilute nitride nanowires, as opposed to GaAsSb nanowires having the same PL emission wavelength, and the observation of room temperature PL demonstrate the advantage of the dilute nitride system offers in the nanowire configuration, providing a pathway for realizing nanoscale optoelectronic devices in the telecommunication wavelength region.

  2. 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.

  3. AlGaAs/InGaAlP tunnel junctions for multijunction solar cells

    SciTech Connect (OSTI)

    SHARPS,P.R.; LI,N.Y.; HILLS,J.S.; HOU,H.; CHANG,PING-CHIH; BACA,ALBERT G.

    2000-05-16

    Optimization of GaInP{sub 2}/GaAs dual and GaInP{sub 2}/GaAs/Ge triple junction cells, and development of future generation monolithic multi-junction cells will involve the development of suitable high bandgap tunnel junctions. There are three criteria that a tunnel junction must meet. First, the resistance of the junction must be kept low enough so that the series resistance of the overall device is not increased. For AMO, 1 sun operation, the tunnel junction resistance should be below 5 x 10{sup {minus}2} {Omega}-cm. Secondly, the peak current density for the tunnel junction must also be larger than the J{sub sc} of the cell so that the tunnel junction I-V curve does not have a deleterious effect on the I-V curve of the multi-junction device. Finally, the tunnel junction must be optically transparent, i.e., there must be a minimum of optical absorption of photons that will be collected by the underlying subcells. The paper reports the investigation of four high bandgap tunnel junctions grown by metal-organic chemical vapor deposition.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. GaP/Si heterojunction Solar Cells

    SciTech Connect (OSTI)

    Saive, R.; Chen, C.; Emmer, H.; Atwater, H.

    2015-05-11

    Improving the efficiency of solar cells requires the introduction of novel device concepts. Recent developments have shown that in Si solar cell technology there is still room for tremendous improvement. Using the heterojunction with intrinsic thin layer (HIT) approach 25.6 % power conversion efficiency was achieved. However, a-Si as a window and passivation layer comes with disadvantages as a-Si shows low conductivity and high parasitic absorption. Therefore, it is likely that using a crystalline material as window layer with high band gab and high mobility can further improve efficiency. We have studied GaP grown by MOCVD on Si with (001) and (112) orientation. We obtained crystalline layers with carrier mobility around 100 cm2/Vs and which passivate Si as confirmed by carrier lifetime measurements. We performed band alignment studies by X-ray photoelectron spectroscopy yielding a valence band offset of 0.3 eV. Comparing this value with the Schottky-model leads to an interface dipole of 0.59 eV. The open circuit voltage increases with increasing doping and is consistent with the theoretical open circuit voltage deduced from work function difference and interface dipole. We obtain an open circuit voltage of 0.38 V for n-doped GaP with doping levels in the order of 10^17 1/cm^3. In our next steps we will increase the doping level further in order to gain higher open circuit voltage. We will discuss the implications of these findings for GaP/Si heterojunction solar cells.

  9. A monolithic white LED with an active region based on InGaN QWs separated by short-period InGaN/GaN superlattices

    SciTech Connect (OSTI)

    Tsatsulnikov, A. F. Lundin, W. V.; Sakharov, A. V.; Zavarin, E. E.; Usov, S. O.; Nikolaev, A. E.; Kryzhanovskaya, N. V.; Synitsin, M. A.; Sizov, V. S.; Zakgeim, A. L.; Mizerov, M. N.

    2010-06-15

    A new approach to development of effective monolithic white-light emitters is described based on using a short-period InGaN/GaN superlattice as a barrier layer in the active region of LED structures between InGaN quantum wells emitting in the blue and yellow-green spectral ranges. The optical properties of structures of this kind have been studied, and it is demonstrated that the use of such a superlattice makes it possible to obtain effective emission from the active region.

  10. 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: Martin.Kuball@bristol.ac.uk; Montes Bajo, M.; Kuball, M. E-mail: Martin.Kuball@bristol.ac.uk; Paskova, T.; Materials Science and Engineering Department, North Carolina State University, Raleigh, North Carolina 27695 ; Evans, K. R.; Leach, J.; Electrical and Computer Engineering Department, Virginia Commonwealth University, Richmond, Virginia 23284 ; Li, X.; Özgür, Ü.; Morkoç, H.; Chabak, K. D.; Crespo, A.; Gillespie, J. K.; Fitch, R.; Kossler, M.; Walker, D. E.; Trejo, M.; Via, G. D.; Blevins, J. D.

    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.

  11. Atomic structure of defects in GaN:Mg grown with Ga polarity

    SciTech Connect (OSTI)

    Liliental-Weber, Z.; Tomaszewicz, T.; Zakharov, D.; Jasinski, J.; O'Keefe, M.A.; Hautakangas, S.; Laakso, A.; Saarinen, K.

    2003-11-25

    Electron microscope phase images, produced by direct reconstruction of the scattered electron wave from a focal series of high-resolution images, were used to determine the nature of defects formed in GaN:Mg crystals. We studied bulk crystals grown from dilute solutions of atomic nitrogen in liquid gallium at high pressure and thin films grown by the MOCVD method. All the crystals were grown with Ga-polarity. In both types of samples the majority of defects were three dimensional Mg-rich hexagonal pyramids with bases on the (0001) plane and six walls on {l_brace}11{und 2}3{r_brace} planes seen in cross-section as triangulars. Some other defects appear in cross-section as trapezoidal (rectangular) defects as a result of presence of truncated pyramids. Both type of defects have hollow centers. They are decorated by Mg on all six side walls and a base. The GaN which grows inside on the defect walls shows polarity inversion. It is shown that change of polarity starts from the defect tip and propagates to the base, and that the stacking sequence changes from ab in the matrix to bc inside the defect. Exchange of the Ga sublattice with the N sublattice within the defect leads to 0.6 {+-} 0.2{angstrom} displacement between Ga sublattices outside and inside the defects. It is proposed that lateral overgrowth of the cavities formed within the defect takes place to restore matrix polarity on the defect base.

  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. Effect of InGaAs interlayer on the properties of GaAs grown on Si (111) substrate by molecular beam epitaxy

    SciTech Connect (OSTI)

    Wen, Lei; Gao, Fangliang; Li, Jingling; Guan, Yunfang; Wang, Wenliang; Zhou, Shizhong; Lin, Zhiting; Zhang, Xiaona; Zhang, Shuguang E-mail: mssgzhang@scut.edu.cn; Li, Guoqiang E-mail: mssgzhang@scut.edu.cn

    2014-11-21

    High-quality GaAs films have been epitaxially grown on Si (111) substrates by inserting an In{sub x}Ga{sub 1−x}As interlayer with proper In composition by molecular beam epitaxy (MBE). The effect of In{sub x}Ga{sub 1−x}As (0 < x < 0.2) interlayers on the properties of GaAs films grown on Si (111) substrates by MBE has been studied in detailed. Due to the high compressive strain between InGaAs and Si, InGaAs undergoes partial strain relaxation. Unstrained InGaAs has a larger lattice constant than GaAs. Therefore, a thin InGaAs layer with proper In composition may adopt a close lattice constant with that of GaAs, which is beneficial to the growth of high-quality GaAs epilayer on top. It is found that the proper In composition in In{sub x}Ga{sub 1−x}As interlayer of 10% is beneficial to obtaining high-quality GaAs films, which, on the one hand, greatly compensates the misfit stress between GaAs film and Si substrate, and on the other hand, suppresses the formation of multiple twin during the heteroepitaxial growth of GaAs film. However, when the In composition does not reach the proper value (∼10%), the In{sub x}Ga{sub 1−x}As adopts a lower strain relaxation and undergoes a lattice constant smaller than unstrained GaAs, and therefore introduces compressive stress to GaAs grown on top. When In composition exceeds the proper value, the In{sub x}Ga{sub 1−x}As will adopt a higher strain relaxation and undergoes a lattice constant larger than unstrained GaAs, and therefore introduces tensile stress to GaAs grown on top. As a result, In{sub x}Ga{sub 1−x}As interlayers with improper In composition introduces enlarged misfit stress to GaAs epilayers grown on top, and deteriorates the quality of GaAs epilayers. This work demonstrates a simple but effective method to grow high-quality GaAs epilayers and brings up a broad prospect for the application of GaAs-based optoelectronic devices on Si substrates.

  14. Altered biodistribution of Ga-67 by intramuscular gold salts

    SciTech Connect (OSTI)

    Moult, R.G.; Bekerman, C. )

    1989-11-01

    The authors observed a deviation from the normal scintigraphic pattern of Ga-67 citrate biodistribution. An 8-year-old black girl with juvenile rheumatoid arthritis, who had been treated with intramuscular injections of gold salts, had a Ga-67 study as part of her workup. The study demonstrated no hepatic uptake, but showed elevated skeletal and renal activity. This characteristic biodistribution of Ga-67 may be due to inhibition of lysosomal enzymes by gold and/or to accumulation of gold in lysosomes. To study these possibilities, the authors reviewed the mechanisms of Ga-67 localization and gold metabolism. Alteration of the Ga-67 citrate scintigraphic pattern due to earlier treatment with gold salts has not been reported previously.

  15. 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.

  16. Preparation and thermoelectric properties of Ga-substituted p-type fully filled skutterudites CeFe{sub 4-x}Ga{sub x}Sb{sub 12}

    SciTech Connect (OSTI)

    Tan, Gangjian; Wang, Shanyu; Tang, Xinfeng; Li, Han; Uher, Ctirad

    2012-12-15

    We demonstrate a successful substitution of Ga at the Fe sites with a solubility limit of -0.11 in the p-type filled skutterudite compounds CeFe{sub 4-x}Ga{sub x}Sb{sub 12}. With increasing Ga content, the electrical conductivity declines while the Seebeck coefficient improves gradually, consistent with the expected decrease in hole concentration due to the extra electrons introduced by Ga. Moreover, the resemblances in electrical transport properties between Ga- and Co-substituted systems with similar composition indicate that Ga doping exerts little influence on the electronic structure near the top of the valence band. The phonon transport is scarcely affected by the introduction of Ga because of negligible differences in atomic masses and sizes of Ga and Fe. The thermoelectric performance of Ga-substituted samples is slightly improved in the temperature range of 600 K to 800 K with respect to that of Ga-free sample, revealing a favorable effect of Ga-substitution on the intermediate temperature power generation application of this promising p-type material. - Graphical abstract: (a-c) Ga successfully substitutes Fe atoms up to x=0.11 in the CeFe{sub 4-x}Ga{sub x}Sb{sub 12}. (d) The introduction of Ga barely affects the electronic structure near E{sub F}. Highlights: Black-Right-Pointing-Pointer Ga as an effective substitute for Fe in p-type skutterudites CeFe{sub 4-x}Ga{sub x}Sb{sub 12}. Black-Right-Pointing-Pointer The solubility limit of Ga at Fe sites is -0.11 in CeFe{sub 4-x}Ga{sub x}Sb{sub 12}. Black-Right-Pointing-Pointer Ga barely affects the electronic structure near the Fermi level.

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

    DOE PAGES-Beta [OSTI]

    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. Survival and Passage of Juvenile Chinook Salmon and Steelhead Passing through Bonneville Dam, 2011

    SciTech Connect (OSTI)

    Ploskey, Gene R.; Batten, G.; Cushing, Aaron W.; Kim, Jin A.; Johnson, Gary E.; Skalski, J. R.; Townsend, Richard L.; Seaburg, Adam; Weiland, Mark A.; Woodley, Christa M.; Hughes, James S.; Carlson, Thomas J.; Carpenter, Scott M.; Deng, Zhiqun; Etherington, D. J.; Fischer, Eric S.; Fu, Tao; Greiner, Michael J.; Hennen, Matthew J.; Martinez, Jayson J.; Mitchell, T. D.; Rayamajhi, Bishes; Zimmerman, Shon A.

    2013-02-15

    Pacific Northwest National Laboratory (PNNL) and subcontractors conducted an acoustic-telemetry study of juvenile salmonid fish passage and survival at Bonneville Dam in 2011. The study was conducted to assess the readiness of the monitoring system for official compliance studies under the 2008 Biological Opinion and Fish Accords and to assess performance measures including route-specific fish passage proportions, travel times, and survival based upon a virtual/paired-release model. The study relied on releases of live Juvenile Salmon Acoustic Telemetry System tagged smolts in the Columbia River and used acoustic telemetry to evaluate the approach, passage, and survival of passing juvenile salmon using a virtual release, paired reference release survival model. This study supports the U.S. Army Corps of Engineers’ continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

  19. Survival and Passage of Juvenile Chinook Salmon and Steelhead Passing Through Bonneville Dam, 2010

    SciTech Connect (OSTI)

    Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Woodley, Christa M.; Deng, Zhiqun; Carlson, Thomas J.; Kim, Jin A.; Royer, Ida M.; Batten, George W.; Cushing, Aaron W.; Carpenter, Scott M.; Etherington, D. J.; Faber, Derrek M.; Fischer, Eric S.; Fu, Tao; Hennen, Matthew J.; Mitchell, T. D.; Monter, Tyrell J.; Skalski, J. R.; Townsend, Richard L.; Zimmerman, Shon A.

    2012-09-01

    Pacific Northwest National Laboratory (PNNL) and subcontractors conducted an acoustic-telemetry study of juvenile salmonid fish passage and survival at Bonneville Dam in 2010. The study was conducted to assess the readiness of the monitoring system for official compliance studies under the 2008 Biological Opinion and Fish Accords and to assess performance measures including route-specific fish passage proportions, travel times, and survival based upon a single-release model. This also was the last year of evaluation of effects of a behavioral guidance device installed in the Powerhouse 2 forebay. The study relied on releases of live Juvenile Salmon Acoustic Telemetry System tagged smolts in the Columbia River and used acoustic telemetry to evaluate the approach, passage, and survival of passing juvenile salmon. This study supports the U.S. Army Corps of Engineers continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

  20. Survival and Passage of Juvenile Chinook Salmon and Steelhead Passing through Bonneville Dam, 2010

    SciTech Connect (OSTI)

    Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Woodley, Christa M.; Deng, Zhiqun; Carlson, Thomas J.; Kim, Jin A.; Royer, Ida M.; Batten, George W.; Cushing, Aaron W.; Carpenter, Scott M.; Etherington, D. J.; Faber, Derrek M.; Fischer, Eric S.; Fu, Tao; Hennen, Matthew J.; Mitchell, Tyler; Monter, Tyrell J.; Skalski, John R.; Townsend, Richard L.; Zimmerman, Shon A.

    2011-12-01

    Pacific Northwest National Laboratory (PNNL) and subcontractors conducted an acoustic-telemetry study of juvenile salmonid fish passage and survival at Bonneville Dam in 2010. The study was conducted to assess the readiness of the monitoring system for official compliance studies under the 2008 Biological Opinion and Fish Accords and to assess performance measures including route-specific fish passage proportions, travel times, and survival based upon a single-release model. This also was the last year of evaluation of effects of a behavioral guidance device installed in the Powerhouse 2 forebay. The study relied on releases of live Juvenile Salmon Acoustic Telemetry System tagged smolts in the Columbia River and used acoustic telemetry to evaluate the approach, passage, and survival of passing juvenile salmon. This study supports the U.S. Army Corps of Engineers continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

  1. Feasibility of Tidal and Ocean Current Energy in False Pass, Aleutian Islands, Alaska final report

    SciTech Connect (OSTI)

    Wright, Bruce Albert

    2014-05-07

    The Aleutian Pribilof Islands Association was awarded a U.S. Department of Energy Tribal Energy Program grant (DE-EE0005624) for the Feasibility of Tidal and Ocean Current Energy in False Pass, Aleutian Islands, Alaska (Project). The goal of the Project was to perform a feasibility study to determine if a tidal energy project would be a viable means to generate electricity and heat to meet long-term fossil fuel use reduction goals, specifically to produce at least 30% of the electrical and heating needs of the tribally-owned buildings in False Pass. The Project Team included the Aleut Region organizations comprised of the Aleutian Pribilof Island Association (APIA), and Aleutian Pribilof Island Community Development Association (APICDA); the University of Alaska Anchorage, ORPC Alaska a wholly-owned subsidiary of Ocean Renewable Power Company (ORPC), City of False Pass, Benthic GeoScience, and the National Renewable Energy Laboratory (NREL). The following Project objectives were completed: collected existing bathymetric, tidal, and ocean current data to develop a basic model of current circulation at False Pass, measured current velocities at two sites for a full lunar cycle to establish the viability of the current resource, collected data on transmission infrastructure, electrical loads, and electrical generation at False Pass, performed economic analysis based on current costs of energy and amount of energy anticipated from and costs associated with the tidal energy project conceptual design and scoped environmental issues. Utilizing circulation modeling, the Project Team identified two target sites with strong potential for robust tidal energy resources in Isanotski Strait and another nearer the City of False Pass. In addition, the Project Team completed a survey of the electrical infrastructure, which identified likely sites of interconnection and clarified required transmission distances from the tidal energy resources. Based on resource and electrical data

  2. SEMI-ANNUAL REPORTS FOR SABINE PASS LIQUEFACTION, LLC - FE DKT. NO.

    Office of Energy Efficiency and Renewable Energy (EERE) (indexed site)

    10-85-LNG et al: | Department of Energy 0-85-LNG et al: SEMI-ANNUAL REPORTS FOR SABINE PASS LIQUEFACTION, LLC - FE DKT. NO. 10-85-LNG et al: SEMI-ANNUAL REPORTS FOR SABINE PASS LIQUEFACTION, LLC - FE Docket Nos.: 10-85-LNG; 10-111-LNG; 13-30-LNG, 13-42-LNG; 13-121-LNG; 14-31-LNG; 14-92-LNG and 15-63-LNG; 15-171-LNG (Orders 2833, 2961-A, 2961-C, 3306, 3307, 3384, 3442, 3695, 3669, 3669-A; 3767 and 3792) April 2011 (249.29 KB) October 2011 (258.87 KB) April 2012 (407.19 KB) October 2012 (2.34

  3. QMP-MVIA: a message passing system for Linux clusters with gigabit Ethernet mesh connections

    SciTech Connect (OSTI)

    Jie Chen; W. Watson III; Robert Edwards; Weizhen Mao

    2004-09-01

    Recent progress in performance coupled with a decline in price for copper-based gigabit Ethernet (GigE) interconnects makes them an attractive alternative to expensive high speed network interconnects (NIC) when constructing Linux clusters. However traditional message passing systems based on TCP for GigE interconnects cannot fully utilize the raw performance of today's GigE interconnects due to the overhead of kernel involvement and multiple memory copies during sending and receiving messages. The overhead is more evident in the case of mesh connected Linux clusters using multiple GigE interconnects in a single host. We present a general message passing system called QMP-MVIA (QCD Message Passing over M-VIA) for Linux clusters with mesh connections using GigE interconnects. In particular, we evaluate and compare the performance characteristics of TCP and M-VIA (an implementation of the VIA specification) software for a mesh communication architecture to demonstrate the feasibility of using M-VIA as a point-to-point communication software, on which QMP-MVIA is based. Furthermore, we illustrate the design and implementation of QMP-MVIA for mesh connected Linux clusters with emphasis on both point-to-point and collective communications, and demonstrate that QMP-MVIA message passing system using GigE interconnects achieves bandwidth and latency that are not only better than systems based on TCP but also compare favorably to systems using some of the specialized high speed interconnects in a switched architecture at much lower cost.

  4. Defect reduction in epitaxial GaSb grown on nanopatterned GaAs substrates using full wafer block copolymer lithography

    SciTech Connect (OSTI)

    Jha, Smita; Liu, C.-C.; Nealey, P. F.; Kuech, T. F.; Kuan, T. S.; Babcock, S. E.; Park, J. H.; Mawst, L. J.

    2009-08-10

    Defect reduction in the large lattice mismatched system of GaSb on GaAs, {approx}7%, was accomplished using full wafer block copolymer (BCP) lithography. A self-assembled BCP mask layer was used to generate a hexagonal pattern of {approx}20 nm holes on {approx}40 nm centers in a 20 nm SiO{sub 2} layer. GaSb growth initially takes place selectively within these holes leading to a dense array of small, strain-relaxed epitaxial GaSb islands. The GaSb grown on the patterned SiO{sub 2} layer exhibits a reduction in the x-ray linewidth attributed to a decrease in the threading dislocation density when compared to blanket pseudomorphic film growth.

  5. Structural and emission properties of InGaAs/GaAs quantum dots emitting at 1.3??m

    SciTech Connect (OSTI)

    Goldmann, Elias Jahnke, Frank; Paul, Matthias; Kettler, Jan; Jetter, Michael; Michler, Peter; Krause, Florian F.; Mller, Knut; Mehrtens, Thorsten; Rosenauer, Andreas

    2014-10-13

    A combined experimental and theoretical study of InGaAs/GaAs quantum dots (QDs) emitting at 1.3??m under the influence of a strain-reducing InGaAs quantum well is presented. We demonstrate a red shift of 2040?nm observed in photoluminescence spectra due to the quantum well. The InGaAs/GaAs QDs grown by metal organic vapor phase epitaxy show a bimodal height distribution (1?nm and 5?nm) and indium concentrations up to 90%. The emission properties are explained with combined tight-binding and configuration-interaction calculations of the emission wavelengths in conjunction with high-resolution scanning transmission electron microscopy investigations of QD geometry and indium concentrations in the QDs, which directly enter the calculations. QD geometries and concentration gradients representative for the ensemble are identified.

  6. 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.

  7. Assessment of the single-pass thick-seam longwall mining method. Final report

    SciTech Connect (OSTI)

    Adam, R.F.J.; Douglas, W.J.

    1982-04-01

    The objectives of the project are a review of the foreign experiences in longwall mining of thick seams, an evaluation of the US thick seam reserves, a mine design, equipment specifications, and an economic study for longwall mining in a single pass up to 16 feet in US conditions. The review of foreign experience shows a steady increase in the maximum height of extraction with several examples in the range of 13 to 15 feet. Longwall face equipment is available up to an 18 feet height of extraction, based upon shields support and shearer loader. There are important reserves of thick coal seams which can be mined by a longwall in a single pass (125 billion tons). In US conditions, a retreating face with a 16 foot height of extraction and a double entry system, driven 10 feet high, are proposed. The face stability can be improved by using a two bench face cut in good geological conditions. The economic study compares longwall mining with the room-and-pillar method. Longwall mining 16 feet high coal in a single pass can compete advantageously with room-and-pillar mining. 74 figures, 14 tables.

  8. Three-Dimensional Geologic Characterization of Geothermal Systems: Astor Pass, Nevada, USA

    SciTech Connect (OSTI)

    Siler, Drew L; Mayhew, Brett; Faulds, James E

    2012-09-30

    Geothermal systems in the Great Basin, USA, are controlled by a variety of fault intersection and fault interaction areas. Understanding the specific geometry of the structures most conducive to geothermal circulation is crucial in order to both mitigate the costs of geothermal exploration (especially drilling) and to identify blind geothermal systems (no surface expression). Astor Pass, Nevada, one such blind geothermal system, lies near the boundary between two distinct structural domains, the Walker Lane and the Basin and Range, and exhibits characteristics of each setting. Both northwest-striking, left-stepping dextral faults of the Walker Lane and kinematically linked northerly striking normal faults associated with the Basin and Range are present at Astor Pass. Previous studies identified a blind geothermal system controlled by the intersection of northwest-striking dextral and north-northwest-striking normal faults. Wells drilled into the southwestern quadrant of the fault intersection yielded 94˚C fluids, with geothermometers suggesting significantly higher maximum temperatures. Additional data, including reprocessed 2D seismic data and petrologic analysis of well cuttings, were integrated with existing and reinterpreted geologic maps and cross-sections to aid construction of a 3D geologic model. This comprehensive 3D integration of multiple data sets allows characterization of the structural setting of the Astor Pass blind geothermal system at a level of detail beyond what independent data interpretation can provide. Our analysis indicates that the blind geothermal system is controlled by two north- to northwest-plunging fault intersections.

  9. Optical properties of multi-stacked InGaAs/GaNAs quantum dot solar cell fabricated on GaAs (311)B substrate

    SciTech Connect (OSTI)

    Shoji, Yasushi; Akimoto, Katsuhiro; Okada, Yoshitaka

    2012-09-15

    Quantum dot solar cells (QDSCs) comprised of 10 stacked pairs of strain-compensated InGaAs/GaNAs QD structure have been fabricated by atomic hydrogen-assisted molecular beam epitaxy. A homogeneous and high-density QD array structure with improved in-plane ordering and total density of {approx}10{sup 12} cm{sup -2} has been achieved on GaAs (311)B grown at 460 Degree-Sign C after stacking. The external quantum efficiency (EQE) of InGaAs/GaNAs QDSC increases in the longer wavelength range due to additive contribution from QD layers inserted in the intrinsic region. The short-circuit current density measured for QDSC is 17.2 mA/cm{sup 2} compared to 14.8 mA/cm{sup 2} of GaAs reference cell. Further, an increase in EQE due to photocurrent production by 2-step photon absorption has been observed at room temperature though it is still small at around 0.1%.

  10. Single photon emission from site-controlled InGaN/GaN quantum dots

    SciTech Connect (OSTI)

    Zhang, Lei; Hill, Tyler A.; Deng, Hui; Teng, Chu-Hsiang; Lee, Leung-Kway; Ku, Pei-Cheng

    2013-11-04

    Single photon emission was observed from site-controlled InGaN/GaN quantum dots. The single-photon nature of the emission was verified by the second-order correlation function up to 90 K, the highest temperature to date for site-controlled quantum dots. Micro-photoluminescence study on individual quantum dots showed linearly polarized single exciton emission with a lifetime of a few nanoseconds. The dimensions of these quantum dots were well controlled to the precision of state-of-the-art fabrication technologies, as reflected in the uniformity of their optical properties. The yield of optically active quantum dots was greater than 90%, among which 13%–25% exhibited single photon emission at 10 K.

  11. 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-μm 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.

  12. Raman spectroscopy of GaP/GaNP core/shell nanowires

    SciTech Connect (OSTI)

    Dobrovolsky, A.; Chen, W. M.; Buyanova, I. A.; Sukrittanon, S.; Kuang, Y. J.; Tu, C. W.

    2014-11-10

    Raman spectroscopy is employed to characterize structural and phonon properties of GaP/GaNP core/shell nanowires (NWs) grown by molecular beam epitaxy on Si substrates. According to polarization-dependent measurements performed on single NWs, the dominant Raman modes associated with zone-center optical phonons obey selection rules in a zinc-blende lattice, confirming high crystalline quality of the NWs. Two additional modes at 360 and 397 cm{sup −1} that are specific to the NW architecture are also detected in resonant Raman spectra and are attributed to defect-activated scattering involving zone-edge transverse optical phonons and surface optical phonons, respectively. It is concluded that the formation of the involved defect states are mainly promoted during the NW growth with a high V/III ratio.

  13. Large linear magnetoresistance in a GaAs/AlGaAs heterostructure

    SciTech Connect (OSTI)

    Aamir, Mohammed Ali Goswami, Srijit Ghosh, Arindam; Baenninger, Matthias; Farrer, Ian; Ritchie, David A.; Tripathi, Vikram; Pepper, Michael

    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.

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

    SciTech Connect (OSTI)

    Choi, Won Hyuck; Abraham, Michael; Yu, Shih-Ying; You, Guanjun; Liu, Jie; Wang, Li; Xu, Jian; Mohney, Suzanne E.

    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.

  15. 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.

  16. Ultrafast dynamics of type-II GaSb/GaAs quantum dots

    SciTech Connect (OSTI)

    Komolibus, K.; Piwonski, T.; Gradkowski, K.; Reyner, C. J.; Liang, B.; Huffaker, D. L.; Huyet, G.; Houlihan, J.

    2015-01-19

    In this paper, room temperature two-colour pump-probe spectroscopy is employed to study ultrafast carrier dynamics in type-II GaSb/GaAs quantum dots. Our results demonstrate a strong dependency of carrier capture/escape processes on applied reverse bias voltage, probing wavelength and number of injected carriers. The extracted timescales as a function of both forward and reverse bias may provide important information for the design of efficient solar cells and quantum dot memories based on this material. The first few picoseconds of the dynamics reveal a complex behaviour with an interesting feature, which does not appear in devices based on type-I materials, and hence is linked to the unique carrier capture/escape processes possible in type-II structures.

  17. Characterization of Cu(In,Ga)Se2 (CIGS) films with varying gallium ratios

    SciTech Connect (OSTI)

    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 has 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.

  18. Development of polarization-controlled multi-pass Thomson scattering system in the GAMMA 10 tandem mirror

    SciTech Connect (OSTI)

    Yoshikawa, M.; Morimoto, M.; Shima, Y.; Kohagura, J.; Sakamoto, M.; Nakashima, Y.; Imai, T. [Plasma Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 (Japan); Yasuhara, R.; Yamada, I.; Kawahata, K.; Funaba, H. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki, Gifu 509-5292 (Japan); Minami, T. [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)

    2012-10-15

    In the GAMMA 10 tandem mirror, the typical electron density is comparable to that of the peripheral plasma of torus-type fusion devices. Therefore, an effective method to increase Thomson scattering (TS) signals is required in order to improve signal quality. In GAMMA 10, the yttrium-aluminum-garnet (YAG)-TS system comprises a laser, incident optics, light collection optics, signal detection electronics, and a data recording system. We have been developing a multi-pass TS method for a polarization-based system based on the GAMMA 10 YAG TS. To evaluate the effectiveness of the polarization-based configuration, the multi-pass system was installed in the GAMMA 10 YAG-TS system, which is capable of double-pass scattering. We carried out a Rayleigh scattering experiment and applied this double-pass scattering system to the GAMMA 10 plasma. The integrated scattering signal was made about twice as large by the double-pass system.

  19. Thermal Design and Characterization of Heterogeneously Integrated InGaP/GaAs HBTs

    DOE PAGES-Beta [OSTI]

    Choi, Sukwon; Peake, Gregory M.; Keeler, Gordon A.; Geib, Kent M.; Briggs, Ronald D.; Beechem, Thomas E.; Shaffer, Ryan A.; Clevenger, Jascinda; Patrizi, Gary A.; Klem, John F.; et al

    2016-04-21

    Flip-chip heterogeneously integrated n-p-n InGaP/GaAs heterojunction bipolar transistors (HBTs) with integrated thermal management on wide-bandgap AlN substrates followed by GaAs substrate removal are demonstrated. Without thermal management, substrate removal after integration significantly aggravates self-heating effects, causing poor I–V characteristics due to excessive device self-heating. An electrothermal codesign scheme is demonstrated that involves simulation (design), thermal characterization, fabrication, and evaluation. Thermoreflectance thermal imaging, electrical-temperature sensitive parameter-based thermometry, and infrared thermography were utilized to assess the junction temperature rise in HBTs under diverse configurations. In order to reduce the thermal resistance of integrated devices, passive cooling schemes assisted by structural modification, i.e.,more » positioning indium bump heat sinks between the devices and the carrier, were employed. By implementing thermal heat sinks in close proximity to the active region of flip-chip integrated HBTs, the junction-to-baseplate thermal resistance was reduced over a factor of two, as revealed by junction temperature measurements and improvement of electrical performance. In conclusion, the suggested heterogeneous integration method accounts for not only electrical but also thermal requirements providing insight into realization of advanced and robust III–V/Si heterogeneously integrated electronics.« less

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. Quaternary AlInGaN/InGaN quantum well on vicinal c-plane substrate for high emission intensity of green wavelengths

    SciTech Connect (OSTI)

    Park, Seoung-Hwan; Pak, Y. Eugene; Park, Chang Young; Mishra, Dhaneshwar; Yoo, Seung-Hyun; Cho, Yong-Hee Shim, Mun-Bo; Kim, Sungjin

    2015-05-14

    Electronic and optical properties of non-trivial semipolar AlInGaN/InGaN quantum well (QW) structures are investigated by using the multiband effective-mass theory and non-Markovian optical model. On vicinal c-plane GaN substrate miscut by a small angle (??GaN/InGaN system is shown to have ?3 times larger spontaneous emission peak intensity than the conventional InGaN/GaN system at green wavelength. It is attributed to much larger optical matrix element of the quaternary AlInGaN/InGaN system, derived from the reduction of internal electric field induced by polarizations. This effect exceeds the performance-degrading factor of smaller quasi-Fermi-level separation for the quaternary AlInGaN/InGaN system than that for the conventional InGaN/GaN system. Results indicate that the use of quaternary III-nitride QWs on vicinal substrates may be beneficial in improving the performance of optical devices emitting green light.

  5. Emission properties of InGaAs/GaAs heterostructures with quantum wells and dots after irradiation with neutrons

    SciTech Connect (OSTI)

    Baidus, N. V.; Vikhrova, O. V. Zvonkov, B. N.; Malysheva, E. I.; Trufanov, A. N.

    2015-03-15

    The effect of neutron radiation on the luminescence of InGaAs/GaAs heterostructures with quantum wells and quantum dots is studied. It is found that neutron radiation results both in the formation of defects and in the radiation-induced annealing of growth-related defects. Quantum dots are more stable to neutron radiation in comparison with quantum wells. It is shown that the layer of InGaAs/GaAs quantum dots located near the surface is less sensitive to irradiation with neutrons compared with a similar layer located in the bulk. In the first case, one can observe an increase in the photoluminescence and electroluminescence intensities after irradiation with neutrons, which is related to the effects of radiation-induced annealing. The pronounced effect of elastic strains in the InGaAs/GaAs quantum wells on the extent of quenching of the photoluminescence intensity upon irradiation with neutrons is revealed. In heterostructures with quantum wells, the effect of radiation-induced annealing manifests itself in a shift of the photoluminescence peak to longer wavelengths as a result of a decrease in elastic strains upon irradiation with neutrons. Doping of the GaAs buffer layer with silicon also reduces the value of this spectral shift.

  6. Outdoor Testing of GaInP2/GaAs Tandem Cells with Top Cell Thickness Varied

    SciTech Connect (OSTI)

    McMahon, W. E.; Emergy, K. E.; Friedman, D. J.; Ottoson, L.; Young, M. S.; Ward, J. S.; Kramer, C. M.; Duda, A.; Kurtz, S.

    2005-08-01

    In this study, we measure the performance of GaInP2/GaAs tandem cells under direct beam sunlight outdoors in order to quantify their sensitivity to both spectral variation and GaInP2 top-cell thickness. A set of cells with five different top-cell thicknesses was mounted on a two-axis tracker with the incident sunlight collimated to exclude all except the direct beam. Current-voltage (I-V) curves were taken throughout the course of several days, along with measurements of the direct solar spectrum. Our two major conclusions are: (1) GaInP2/GaAs tandem cells designed for either the ASTM G-173 direct (G-173D) spectrum or the "air mass 1.5 global" (AM1.5G) spectrum perform the best, and (2) cells can be characterized indoors and modeled using outdoor spectra with the same result. These results are equally valid for GaInP2/GaAs/Ge triple-junction cells.

  7. 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}.

  8. Case History of a Clean Water Act Compliance Agreement at the Rocky Flats Environmental Technology Site near Golden, Colorado

    SciTech Connect (OSTI)

    Thompson, J.S.

    1995-08-01

    A major Clean Water Act (CWA) Federal Facilities Compliance Agreement was signed on March 25, 1991 by the US Department of Energy, Rocky Flats Field Office (DOE, RFFO) and the Water Enforcement Division of the Environmental Protection Agency (EPA), Region VIII. The agreement revised the Rocky Flats Plant`s National Pollutant Discharge Elimination System (NPDES) permit and arose from pemittee-requested changes in effluent monitoring points and permit violations, most notably the February 22, 1989 Chromic Acid Incident. The Rocky Flats Plant, now called the Rocky Flats Environmental Technology Site (Site) near Golden Colorado was operated at that time by Rockwell International Corporation, who later plead guilty to six misdemeanor and felony counts of the CWA (the aforementioned NPDES permit violations) and paid a $4 million fine on March 26, 1992. The Compliance Agreement, hereafter referred to as the NPDES FFCA, called for three separate remedial action plans and contained a schedule for their submittal to the EPA. The compliance plans focussed on: (1) Waste Water Treatment Plant (WWTP) performance upgrades, (2) source control and surface water protection, and (3) characterization of the impacts from past sludge disposal practices. Projects that implemented the compliance plans were initiated soon after submittal to the EPA and are forecast to complete in 1997 at a total cost of over $35 million. This paper presents a case history of NPDES FFCA compliance projects and highlights the successes, failures, and lessons learned.

  9. Simultaneous cloning and expression of two cellulase genes from Bacillus subtilis newly isolated from Golden Takin (Budorcas taxicolor Bedfordi)

    SciTech Connect (OSTI)

    Li, Wang; College of Animal Science, Henan Science and Technology University, Luoyang 471003 ; Huan, Xiajuan; Zhou, Ying; Ma, Qingyi; Chen, Yulin

    2009-06-12

    A bacterial strain with high cellulase activity was isolated of feces sample of Golden Takin (Budorcas taxicolor Bedfordi). The bacterium was classified and designated Bacillus subtilis LN by morphological and 16SrDNA gene sequence analysis. Two putative cellulase genes, CelL15 and CelL73, were simultaneously cloned from the isolated strain by PCR. The putative gene CelL15 consisted of an open reading frame (ORF) of 1470 nucleotides and encoded a protein of 490 amino acids with a molecular weight of 54 kDa. The CelL73 gene consisted of an open reading frame (ORF) of 741 nucleotides and encoded a protein of 247 amino acids with a molecular weight of 27 kDa. Both genes were purified and cloned into pET-28a for expression in Escherichia coli BL21 (DE3). The ability of E. coli to degrade cellulose was enhanced when the two recombinants were cultured together.

  10. 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.

  11. Microscopic, electrical and optical studies on InGaN/GaN quantum wells based LED devices

    SciTech Connect (OSTI)

    Mutta, Geeta Rani; Venturi, Giulia; Castaldini, Antonio; Cavallini, Anna

    2014-02-21

    We report here on the micro structural, electronic and optical properties of a GaN-based InGaN/GaN MQW LED grown by the MOVPE method. The present study shows that the threading dislocations present in these LED structures are terminated as V pits at the surface and have an impact on the electrical and optical activity of these devices. It has been pointed that these dislocations were of edge, screw and mixed types. EBIC maps suggest that the electrically active defects are screw and mixed dislocations and behave as nonradiative recombinant centres.

  12. 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.

  13. 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; Chen, Weixi; Ding, Ying

    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.

  14. Characterization of Cu(In,Ga)Se2 (CIGS) films with varying gallium ratios

    DOE PAGES-Beta [OSTI]

    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

  15. 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.

  16. 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.

  17. Wake deficit measurements on the Jess and Souza Ranches, Altamont Pass

    SciTech Connect (OSTI)

    Nierenburg, R. (Altamont Energy Corp., San Rafael, CA (USA))

    1990-04-01

    This report is ninth in a series of documents presenting the findings of field test under DOE's Cooperative Field Test Program (CFTP) with the wind industry. This report provides results of a project conducted by Altamont Energy Corp. (AEC) to measure wake deficits on the Jess and Sousa Ranches in Altamont Pass, CA. This research enhances and complements other DOE-funded projects to refine estimates of wind turbine array effects. This project will help explain turbine performance variability caused by wake effects. 4 refs., 28 figs., 106 tabs.

  18. Laboratory Studies of the Effects of Pressure and Dissolved Gas Supersaturation on Turbine-Passed Fish

    SciTech Connect (OSTI)

    Neitzel, Duane A.

    2009-09-14

    Migratory and resident fish in the Columbia River Basin are exposed to stresses associated with hydroelectric power production, including changes in pressure as they pass through turbines and dissolved gas supersaturation (resulting from the release of water from the spillway). To examine pressure changes as a source of turbine-passage injury and mortality, Pacific Northwest National Laboratory scientists conducted specific tests using a hyperbaric chamber. Tests were designed to simulate Kaplan turbine passage conditions and to quantify the response of fish to rapid pressure changes, with and without the complication of fish being acclimated to gas-supersaturated water.

  19. Price of Sabine Pass, LA Liquefied Natural Gas Exports to Argentina

    U.S. Energy Information Administration (EIA) (indexed site)

    (Dollars per Thousand Cubic Feet) Argentina (Dollars per Thousand Cubic Feet) Price of Sabine Pass, LA Liquefied Natural Gas Exports to Argentina (Dollars per Thousand Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2016 4.16 4.71 4.51 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Price of Liquefied Natural Gas Exports by

  20. Price of Sabine Pass, LA Liquefied Natural Gas Exports to Dominican

    U.S. Energy Information Administration (EIA) (indexed site)

    Republic (Dollars per Thousand Cubic Feet) Dominican Republic (Dollars per Thousand Cubic Feet) Price of Sabine Pass, LA Liquefied Natural Gas Exports to Dominican Republic (Dollars per Thousand Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2016 5.41 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Price of Liquefied

  1. Price of Sabine Pass, LA Liquefied Natural Gas Exports to Jordan (Dollars

    U.S. Energy Information Administration (EIA) (indexed site)

    per Thousand Cubic Feet) Jordan (Dollars per Thousand Cubic Feet) Price of Sabine Pass, LA Liquefied Natural Gas Exports to Jordan (Dollars per Thousand Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2016 5.81 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Price of Liquefied Natural Gas Exports by Point of Exit Sabine

  2. Price of Sabine Pass, LA Liquefied Natural Gas Exports to Mexico (Dollars

    U.S. Energy Information Administration (EIA) (indexed site)

    per Thousand Cubic Feet) Mexico (Dollars per Thousand Cubic Feet) Price of Sabine Pass, LA Liquefied Natural Gas Exports to Mexico (Dollars per Thousand Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2016 4.23 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Price of Liquefied Natural Gas Exports by Point of Exit Sabine

  3. Price of Sabine Pass, LA Liquefied Natural Gas Exports to United Arab

    U.S. Energy Information Administration (EIA) (indexed site)

    Emirates (Dollars per Thousand Cubic Feet) United Arab Emirates (Dollars per Thousand Cubic Feet) Price of Sabine Pass, LA Liquefied Natural Gas Exports to United Arab Emirates (Dollars per Thousand Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2016 4 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 10/31/2016 Next Release Date: 11/30/2016 Referring Pages: U.S. Price of Liquefied

  4. STRUCTURAL CONTROLS OF THE EMERSON PASS GEOTHERMAL SYSTEM, NORTHWESTERN NEVADA: CHARACTERIZATION OF A "BLIND" SYSTEM

    SciTech Connect (OSTI)

    Anderson, Ryan B; Faulds, James E

    2012-12-03

    Detailed geologic analyses have elucidated the kinematics, stress state, structural controls, and past surface activity of a blind geothermal system in Emerson Pass on the Pyramid Lake Paiute Reservation, western Nevada. The Emerson Pass area resides near the boundary of the Basin and Range and Walker Lane provinces and at the western edge of a broad left step or relay ramp between the north- to north-northeast-striking, west-dipping, Fox and Lake Range normal faults. The step-over provides a structurally favorable setting for deep circulation of meteoric fluids. Strata in the area are comprised of late Miocene to Pliocene sedimentary rocks and the middle Miocene Pyramid sequence mafic to intermediate volcanic rocks, all overlying Mesozoic metasedimentary and intrusive rocks. A thermal anomaly was discovered in Emerson Pass by use of 2-m temperature surveys deployed within a structurally favorable setting and proximal to surface features indicative of geothermal activity. The 2-m temperature surveys define a north-south elongate thermal anomaly that has a maximum recorded temperature of ~60°C and resides on a north- to north-northeast-striking normal fault. Although the active geothermal system is expressed solely as a soil heat anomaly, late Pleistocene travertine and tufa mounds, chalcedonic silica/calcite veins, and silica cemented Pleistocene lacustrine gravels indicate a robust geothermal system was active at the surface in the recent past. The geothermal system is controlled primarily by the broad step-over between two major range-bounding normal faults. In detail, the system likely results from enhanced permeability generated by the intersection of two oppositely dipping, southward terminating north- to north-northwest-striking (Fox Range fault) and north-northeast-striking normal faults. Structural complexity and spatial heterogeneities of the strain and stress field have developed in the step-over region, but kinematic data suggest a west

  5. Method and system for compact, multi-pass pulsed laser amplifier

    DOE Patents [OSTI]

    Erlandson, Alvin Charles

    2014-11-25

    A laser amplifier includes an input aperture operable to receive laser radiation having a first polarization, an output aperture coupled to the input aperture by an optical path, and a polarizer disposed along an optical path. A transmission axis of the polarizer is aligned with the first polarization. The laser amplifier also includes n optical switch disposed along the optical path. The optical switch is operable to pass the laser radiation when operated in a first state and to reflect the laser radiation when operated in a second state. The laser amplifier further includes an optical gain element disposed along the optical path and a polarization rotation device disposed along the optical path.

  6. Trap states in enhancement-mode double heterostructures AlGaN/GaN high electron mobility transistors with different GaN channel layer thicknesses

    SciTech Connect (OSTI)

    He, Yunlong; Wang, Chong Li, Xiangdong; Zhao, Shenglei; Mi, Minhan; Pei, Jiuqing; Zhang, Jincheng; Hao, Yue; Li, Peixian; Ma, Xiaohua

    2015-08-10

    This is the report on trap states in enhancement-mode AlGaN/GaN/AlGaN double heterostructures high electron mobility transistors by fluorine plasma treatment with different GaN channel layer thicknesses. Compared with the thick GaN channel layer sample, the thin one has smaller 2DEG concentration, lower electron mobility, lower saturation current, and lower peak transconductance, but it has a higher threshold voltage of 1.2 V. Deep level transient spectroscopy measurements are used to obtain the accurate capture cross section of trap states. By frequency dependent capacitance and conductance measurements, the trap state density of (1.98–2.56) × 10{sup 12 }cm{sup −2} eV{sup −1} is located at E{sub T} in a range of (0.37–0.44) eV in the thin sample, while the trap state density of (2.3–2.92) × 10{sup 12 }cm{sup −2} eV{sup −1} is located at E{sub T} in a range of (0.33–0.38) eV in the thick one. It indicates that the trap states in the thin sample are deeper than those in the thick one.

  7. 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.

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

    DOE Patents [OSTI]

    Mirzadeh, Saed; Whipple, Richard E.; Grant, Patrick M.; O'Brien, Jr., Harold A.

    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.

  9. Reactive codoping of GaAlInP compound semiconductors (Patent...

    Office of Scientific and Technical Information (OSTI)

    Report Number(s): 7,329,554 US patent application DOE Contract Number: AC36-99GO10337 Resource Type: Patent Research Org: National Renewable Energy Laboratory (NREL), Golden, CO

  10. 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.

  11. Towards Molecular Dynamics Simulations of InGaN Nanostructures.

    Office of Scientific and Technical Information (OSTI)

    (Conference) | SciTech Connect Towards Molecular Dynamics Simulations of InGaN Nanostructures. Citation Details In-Document Search Title: Towards Molecular Dynamics Simulations of InGaN Nanostructures. Abstract not provided. Authors: Zhou, Xiaowang ; Jones, Reese E. Publication Date: 2015-05-01 OSTI Identifier: 1258140 Report Number(s): SAND2015-4035C 584006 DOE Contract Number: AC04-94AL85000 Resource Type: Conference Resource Relation: Conference: Proposed for presentation at the 2015

  12. Towards Molecular Dynamics Simulations of InGaN Nanostructures.

    Office of Scientific and Technical Information (OSTI)

    (Conference) | SciTech Connect Towards Molecular Dynamics Simulations of InGaN Nanostructures. Citation Details In-Document Search Title: Towards Molecular Dynamics Simulations of InGaN Nanostructures. Abstract not provided. Authors: Zhou, Xiaowang ; Jones, Reese E. Publication Date: 2015-05-01 OSTI Identifier: 1258265 Report Number(s): SAND2015-4035C 584006 DOE Contract Number: AC04-94AL85000 Resource Type: Conference Resource Relation: Conference: Proposed for presentation at the 2015

  13. 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.

  14. Non-destructive single-pass low-noise detection of ions in a beamline

    SciTech Connect (OSTI)

    Schmidt, Stefan; Murböck, Tobias; Birkl, Gerhard; Andelkovic, Zoran; Vogel, Manuel; Nörtershäuser, Wilfried; Stahl, Stefan

    2015-11-15

    We have conceived, built, and operated a device for the non-destructive single-pass detection of charged particles in a beamline. The detector is based on the non-resonant pick-up and subsequent low-noise amplification of the image charges induced in a cylindrical electrode surrounding the particles’ beam path. The first stage of the amplification electronics is designed to be operated from room temperature down to liquid helium temperature. The device represents a non-destructive charge counter as well as a sensitive timing circuit. We present the concept and design details of the device. We have characterized its performance and show measurements with low-energy highly charged ions (such as Ar{sup 13+}) passing through one of the electrodes of a cylindrical Penning trap. This work demonstrates a novel approach of non-destructive, low noise detection of charged particles which is, depending on the bunch structure, suitable, e.g., for ion traps, low-energy beamlines or accelerator transfer sections.

  15. Broadband control of emission wavelength of InAs/GaAs quantum dots by GaAs capping temperature

    SciTech Connect (OSTI)

    Kaizu, Toshiyuki; Matsumura, Takuya; Kita, Takashi

    2015-10-21

    We investigated the effects of the GaAs capping temperature on the morphological and photoluminescence (PL) properties of InAs quantum dots (QDs) on GaAs(001). The broadband tuning of the emission wavelength from 1.1 to 1.3 μm was achieved at room temperature by only adjusting the GaAs capping temperature. As the capping temperature was decreased, the QD shrinkage due to In desorption and In-Ga intermixing during the capping process was suppressed. This led to QDs with a high aspect ratio, and resultantly, the emission wavelength shifted toward the longer-wavelength side. In addition, the linearly polarized PL intensity elucidated anisotropic characteristics reflecting the shape anisotropy of the embedded QDs, in which a marked change in polarization anisotropy occurred at capping temperatures lower than 460 °C.

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

    SciTech Connect (OSTI)

    Sztein, Alexander; Bowers, John E.; DenBaars, Steven P.; Nakamura, Shuji

    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.

  17. A new InGaP/GaAs tunneling heterostructure-emitter bipolar transistor (T-HEBT)

    SciTech Connect (OSTI)

    Tsai, Jung-Hui; Lee, Ching-Sung; Lour, Wen-Shiung; Ma, Yung-Chun; Ye, Sheng-Shiun

    2011-05-15

    Excellent characteristics of an InGaP/GaAs tunneling heterostructure-emitter bipolar transistor (T-HEBT) are first demonstrated. The insertion of a thin n-GaAs emitter layer between tynneling confinement and base layers effectivelty eliminates the potential spike at base-emitter junction and reduces the collector-emitter offset voltage, while the thin InGaP tunneling confinement layer is employed to reduce the transporting time across emitter region for electrons and maintain the good confinement effect for holes. Experimentally, the studied T-HEBN exhibits a maximum current gain of 285, a relatively low offset voltage of 40 mW, and a current-gain cutoff frequency of 26.4 GHz.

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

    SciTech Connect (OSTI)

    zduran, Mustafa; Turgut, Kemal; Arikan, Nihat; ?yigr, 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.

  19. Structural transformations in amorphous ↔ crystalline phase change of Ga-Sb alloys

    SciTech Connect (OSTI)

    Edwards, T. G.; Sen, S.; Hung, I.; Gan, Z.; Kalkan, B.; Raoux, S.

    2013-12-21

    Ga-Sb alloys with compositions ranging between ∼12 and 50 at. % Ga are promising materials for phase change random access memory applications. The short-range structures of two such alloys with compositions Ga{sub 14}Sb{sub 86} and Ga{sub 46}Sb{sub 54} are investigated, in their amorphous and crystalline states, using {sup 71}Ga and {sup 121}Sb nuclear magnetic resonance spectroscopy and synchrotron x-ray diffraction. The Ga and Sb atoms are fourfold coordinated in the as-deposited amorphous Ga{sub 46}Sb{sub 54} with nearly 40% of the constituent atoms being involved in Ga-Ga and Sb-Sb homopolar bonding. This necessitates extensive bond switching and elimination of homopolar bonds during crystallization. On the other hand, Ga and Sb atoms are all threefold coordinated in the as-deposited amorphous Ga{sub 14}Sb{sub 86}. Crystallization of this material involves phase separation of GaSb domains in Sb matrix and a concomitant increase in the Ga coordination number from 3 to 4. Results from crystallization kinetics experiments suggest that the melt-quenching results in the elimination of structural “defects” such as the homopolar bonds and threefold coordinated Ga atoms in the amorphous phases of these alloys, thereby rendering them structurally more similar to the corresponding crystalline states compared to the as-deposited amorphous phases.

  20. Mismatch relaxation by stacking fault formation of AlN islands in AlGaN/GaN structures on m-plane GaN substrates

    SciTech Connect (OSTI)

    Smalc-Koziorowska, Julita; Sawicka, Marta; Skierbiszewski, Czeslaw; Grzegory, Izabella

    2011-08-08

    We study the mismatch relaxation of 2-5 nm thin elongated AlN islands formed during growth of AlGaN on bulk m-plane GaN by molecular beam epitaxy. The relaxation of these m-plane AlN layers is anisotropic and occurs through the introduction of stacking faults in [0001] planes during island coalescence, while no relaxation is observed along the perpendicular [1120] direction. This anisotropy in the mismatch relaxation and the formation of stacking faults in the AlN islands are explained by the growth mode of the AlN platelets and their coalescence along the [0001] direction.

  1. Atomic-column scanning transmission electron microscopy analysis of misfit dislocations in GaSb/GaAs quantum dots

    DOE PAGES-Beta [OSTI]

    Chisholm, Matthew F.; Fernandez-Delgado, N.; Herrera, M.; Kamarudin, M. A.; Zhuang, Q. D.; Hayne, M.; Molina, S. I.

    2016-05-17

    The structural quality of GaSb/GaAs quantum dots (QDs) has been analyzed at atomic scale by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy. In particular, we have studied the misfit dislocations that appear because of the high-lattice mismatch in the heterostructure. Our results have shown the formation of Lomer dislocations not only at the interface between the GaSb QDs and the GaAs substrate, but also at the interface with the GaAs capping layer, which is not a frequent observation. The analysis of these dislocations points to the existence of chains of dislocation loops around the QDs. The dislocation core ofmore » the observed defects has been characterized, showing that they are reconstructed Lomer dislocations, which have less distortion at the dislocation core in comparison to unreconstructed ones. As a result, strain measurements using geometric phase analysis show that these dislocations may not fully relax the strain due to the lattice mismatch in the GaSb QDs.« less

  2. Efficient carrier relaxation and fast carrier recombination of N-polar InGaN/GaN light emitting diodes

    SciTech Connect (OSTI)

    Feng, Shih-Wei Liao, Po-Hsun; Leung, Benjamin; Han, Jung; Yang, Fann-Wei; Wang, Hsiang-Chen

    2015-07-28

    Based on quantum efficiency and time-resolved electroluminescence measurements, the effects of carrier localization and quantum-confined Stark effect (QCSE) on carrier transport and recombination dynamics of Ga- and N-polar InGaN/GaN light-emitting diodes (LEDs) are reported. The N-polar LED exhibits shorter ns-scale response, rising, delay, and recombination times than the Ga-polar one does. Stronger carrier localization and the combined effects of suppressed QCSE and electric field and lower potential barrier acting upon the forward bias in an N-polar LED provide the advantages of more efficient carrier relaxation and faster carrier recombination. By optimizing growth conditions to enhance the radiative recombination, the advantages of more efficient carrier relaxation and faster carrier recombination in a competitive performance N-polar LED can be realized for applications of high-speed flash LEDs. The research results provide important information for carrier transport and recombination dynamics of an N-polar InGaN/GaN LED.

  3. 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.

  4. Geology and geothermal resources of the Santiam Pass area of the Oregon Cascade Range, Deschutes, Jefferson and Linn Counties, Oregon

    SciTech Connect (OSTI)

    Hill, B.E. (ed.)

    1992-10-01

    This open-file report presents the results of the Santiam Pass drilling program. The first phase of this program was to compile all available geological, geophysical and geothermal data for the Santiam Pass area and select a drill site on the basis of these data (see Priest and others, 1987a), A summary of the drilling operations and costs associated with the project are presented in chapter 1 by Hill and Benoit. An Overview of the geology of the Santiam Pass area is presented by Hill and Priest in chapter 2. Geologic mapping and isotopic age determinations in the Santiam Pass-Mount Jefferson area completed since 1987 are summarized in chapter 2. One of the more important conclusions reached in chapter 2 is that a minimum of 2 km vertical displacement has occurred in the High Cascade graben in the Santiam Pass area. The petrology of the Santiam Pass drill core is presented by Hill in chapter 3. Most of the major volcanic units in the core have been analyzed for major, minor, and trace element abundances and have been studied petrographically. Three K-Ar ages are interpreted in conjunction with the magnetostratigraphy of the core to show that the oldest rocks in the core are approximately 1.8 Ma. Geothermal and geophysical data collected from the Santiam Pass well are presented by Blackwell in chapter 4. The Santiam Pass well failed to penetrate beneath the zone of lateral groundwater flow associated with highly permeable Quaternary volcanic rocks. Calculated geothermal gradients range from about 50[degree]C/km at depth 700-900 m, to roughly 110[degree]C/km from 900 m to the bottom of the well at 929 m. Heat-flow values for the bottom part of the hole bracket the regional average for the High Cascades. Blackwell concludes that heat flow along the High Cascades axis is equal to or higher than along the western edge of the High Cascades.

  5. Making it pay in Athens, GA

    SciTech Connect (OSTI)

    Malloy, M.G.

    1997-04-01

    The materials recovery facility (MRF) in Athens, GA, is a well-fed recycling facility. But, if the local government has its way, it will be even better fed in the near future. The Athens-Clarke County (ACC) regional municipality in which the facility resides has a put-or-pay contract with the plant`s owner/operator, under which the more it feeds the MRF, the more money it receives in return, through the sale of recycled end products. The ACC Solid Waste Department uses a volume-based waste collection system that encourages residents to recycle--the more they recycle, the less trash they have to put out, and the less they pay each month. The Athens facility, which will be a featured site tour at next month`s WasteExpo `97 in nearby Atlanta, had its ground-breaking two years ago, in April 1995. ACC is responsible for delivering material--or seeing that recyclables are delivered--to the MRF, which is owned and operated by Resource Recovery Systems (RRS, Centerbrook, Conn.). Over the past year, ACC has stepped up various incentives for businesses to recycle and send their recyclables to the facility, including instituting pilot programs for commercial interests that offer them versions of volume-based collection similar to that done by residents.

  6. High Voltage GaN Schottky Rectifiers

    SciTech Connect (OSTI)

    CAO,X.A.; CHO,H.; CHU,S.N.G.; CHUO,C.-C.; CHYI,J.-I.; DANG,G.T.; HAN,JUNG; LEE,C.-M.; PEARTON,S.J.; REN,F.; WILSON,R.G.; ZHANG,A.P.

    1999-10-25

    Mesa and planar GaN Schottky diode rectifiers with reverse breakdown voltages (V{sub RB}) up to 550V and >2000V, respectively, have been fabricated. The on-state resistance, R{sub ON}, was 6m{Omega}{center_dot} cm{sup 2} and 0.8{Omega}cm{sup 2}, respectively, producing figure-of-merit values for (V{sub RB}){sup 2}/R{sub ON} in the range 5-48 MW{center_dot}cm{sup -2}. At low biases the reverse leakage current was proportional to the size of the rectifying contact perimeter, while at high biases the current was proportional to the area of this contact. These results suggest that at low reverse biases, the leakage is dominated by the surface component, while at higher biases the bulk component dominates. On-state voltages were 3.5V for the 550V diodes and {ge}15 for the 2kV diodes. Reverse recovery times were <0.2{micro}sec for devices switched from a forward current density of {approx}500A{center_dot}cm{sup -2} to a reverse bias of 100V.

  7. 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 Mller, Marcus; Veit, Peter; Bertram, Frank; Christen, Jrgen; Glauser, Marlene; Carlin, Jean-Franois; Cosendey, Gatien; Butt, Raphal; 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.

  8. Thermoelectric properties and nonstoichiometry of GaGeTe

    SciTech Connect (OSTI)

    Drasar, C.; Kucek, V.; Benes, L.; Lostak, P.; Vlcek, M.

    2012-09-15

    Polycrystalline samples of composition Ga{sub 1+x}Ge{sub 1-x}Te (x=-0.03 Division-Sign 0.07) and GaGeTe{sub 1-y} (y=-0.02 Division-Sign 0.02) were synthesized from elements of 5 N purity using a solid state reaction. The products of synthesis were identified by X-ray diffraction; phase purity and microstructure were examined by EDX/SEM. Samples for measurement of transport properties were prepared using hot-pressing. They were characterized by measurement of electrical conductivity, the Hall coefficient, and the Seebeck coefficient over a temperature range 80-480 K and of thermal conductivity over a temperature range 300-580 K. All samples show p-type conductivity. We discuss the influence of stoichiometry on the phase purity of the samples and on free carrier concentration. The investigation of thermoelectric properties shows that the power factor of these samples is low compared to state-of-the-art materials at room temperature but increases distinctly with temperature. - Graphical abstract: Structure and preparation of GaGeTe. Electrical conductivity {sigma}, the Hall coefficient R{sub H}, the Seebeck coefficient S and thermal conductivity {kappa} as a function of temperature for the Ga{sub 1.01}Ge{sub 0.99}Te{sub 0.99} sample. Highlights: Black-Right-Pointing-Pointer We explore thermoelectric and transport properties of Ga{sub 1+x}Ge{sub 1-x}Te and GaGeTe{sub 1-y}. Black-Right-Pointing-Pointer GaGeTe is p-type degenerate semiconductor; the hole concentration increase with x and y. Black-Right-Pointing-Pointer Maximum power factor {sigma}S{sup 2}=3.6 Multiplication-Sign 10{sup -4} Wm{sup -1} K{sup -2} at 475 K.

  9. High Quantum Efficiency AlGaN/InGaN Photodetectors

    SciTech Connect (OSTI)

    Buckley, James H; Leopold, Daniel

    2009-11-24

    High efficiency photon counting detectors in use today for high energy particle detection applications have a significant spectral mismatch with typical sources and have a number of practical problems compared with conventional bialkali photomultiplier tubes. Numerous high energy physics experiments that employ scintillation light detectors or Cherenkov detectors would benefit greatly from photomultipliers with higher quantum efficiencies. The need for extending the sensitivity of photon detectors to the blue and UV wavebands comes from the fact that both Cherenkov light and some scintillators have an emission spectrum which is peaked at short wavelengths. This research involves the development of high quantum efficiency, high gain, UV/blue photon counting detectors based on AlGaN/InGaN photocathode heterostructures grown by molecular beam epitaxy (MBE). The work could eventually lead to nearly ideal light detectors with a number of distinct advantages over existing technologies for numerous applications in high-energy physics and particle astrophysics. Potential advantages include much lower noise detection, better stability and radiation resistance than other cathode structures, very low radioactive background levels for deep underground experiments and high detection efficiency of individual UV-visible photons. We are also working on the development of photocathodes with intrinsic gain, initially improving the detection efficiency of hybrid semiconductor-vacuum tube devices, and eventually leading to an all-solid-state photomultiplier device.

  10. Enhanced optical property in quaternary GaInAsSb/AlGaAsSb quantum wells

    SciTech Connect (OSTI)

    Lin, Chien-Hung Lee, Chien-Ping

    2014-10-21

    High quality GaInAsSb/AlGaAsSb quantum wells (QWs) have been grown by molecular beam epitaxy using proper interface treatments. By controlling the group-V elements at interfaces, we obtained excellent optical quality QWs, which were free from undesired localized trap states, which may otherwise severely affect the exciton recombination. Strong and highly efficient exciton emissions up to room temperature with a wavelength of 2.2 μm were observed. A comprehensive investigation on the QW quality was carried out using temperature dependent and power dependent photoluminescence (PL) measurements. The PL emission intensity remains nearly constant at low temperatures and is free from the PL quenching from the defect induced localized states. The temperature dependent emission energy had a bulk-like behavior, indicating high quality well/barrier interfaces. Because of the uniformity of the QWs and smooth interfaces, the low temperature limit of inhomogeneous line width broadening is as small as 5 meV.

  11. The possibly important role played by Ga{sub 2}O{sub 3} during the activation of GaN photocathode

    SciTech Connect (OSTI)

    Fu, Xiaoqian E-mail: 214808748@qq.com; Wang, Honggang; Zhang, Junju; Li, Zhiming; Cui, Shiyao; Zhang, Lejuan

    2015-08-14

    Three different chemical solutions are used to remove the possible contamination on GaN surface, while Ga{sub 2}O{sub 3} is still found at the surface. After thermal annealing at 710 °C in the ultrahigh vacuum (UHV) chamber and activated with Cs/O, all the GaN samples are successfully activated to the effective negative electron affinity (NEA) photocathodes. Among all samples, the GaN sample with the highest content of Ga{sub 2}O{sub 3} after chemical cleaning obtains the highest quantum efficiency. By analyzing the property of Ga{sub 2}O{sub 3}, the surface processing results, and electron affinity variations during Cs and Cs/O{sub 2} deposition on GaN of other groups, it is suggested that before the adsorption of Cs, Ga{sub 2}O{sub 3} is not completely removed from GaN surface in our samples, which will combine with Cs and lead to a large decrease in electron affinity. Furthermore, the effective NEA is formed for GaN photocathode, along with the surface downward band bending. Based on this assumption, a new dipole model Ga{sub 2}O{sub 3}-Cs is suggested, and the experimental effects are explained and discussed.

  12. Strain relaxation in GaN/Al{sub x}Ga{sub 1-x}N superlattices grown by plasma-assisted molecular-beam epitaxy

    SciTech Connect (OSTI)

    Kotsar, Y.; Bellet-Amalric, E.; Das, A.; Monroy, E.; Sarigiannidou, E.

    2011-08-01

    We have investigated the misfit relaxation process in GaN/Al{sub x}Ga{sub 1-x}N (x = 0.1, 0.3, 0.44) superlattices (SL) deposited by plasma-assisted molecular beam epitaxy. The SLs under consideration were designed to achieve intersubband absorption in the mid-infrared spectral range. We have considered the case of growth on GaN (tensile stress) and on AlGaN (compressive stress) buffer layers, both deposited on GaN-on-sapphire templates. Using GaN buffer layers, the SL remains almost pseudomorphic for x = 0.1, 0.3, with edge-type threading dislocation densities below 9 x 10{sup 8} cm{sup -2} to 2 x 10{sup 9} cm{sup -2}. Increasing the Al mole fraction to 0.44, we observe an enhancement of misfit relaxation resulting in dislocation densities above 10{sup 10} cm{sup -2}. In the case of growth on AlGaN, strain relaxation is systematically stronger, with the corresponding increase in the dislocation density. In addition to the average relaxation trend of the SL, in situ measurements indicate a periodic fluctuation of the in-plane lattice parameter, which is explained by the different elastic response of the GaN and AlGaN surfaces to the Ga excess at the growth front. The results are compared with GaN/AlN SLs designed for near-infrared intersubband absorption.

  13. Enhanced sheet carrier densities in polarization controlled AlInN/AlN/GaN/InGaN field-effect transistor on Si (111)

    SciTech Connect (OSTI)

    Hennig, J. Dadgar, A.; Witte, H.; Bläsing, J.; Lesnik, A.; Strittmatter, A.; Krost, A.

    2015-07-15

    We report on GaN based field-effect transistor (FET) structures exhibiting sheet carrier densities of n = 2.9 10{sup 13} cm{sup −2} for high-power transistor applications. By grading the indium-content of InGaN layers grown prior to a conventional GaN/AlN/AlInN FET structure control of the channel width at the GaN/AlN interface is obtained. The composition of the InGaN layer was graded from nominally x{sub In} = 30 % to pure GaN just below the AlN/AlInN interface. Simulations reveal the impact of the additional InGaN layer on the potential well width which controls the sheet carrier density within the channel region of the devices. Benchmarking the In{sub x}Ga{sub 1−x}N/GaN/AlN/Al{sub 0.87}In{sub 0.13}N based FETs against GaN/AlN/AlInN FET reference structures we found increased maximum current densities of I{sub SD} = 1300 mA/mm (560 mA/mm). In addition, the InGaN layer helps to achieve broader transconductance profiles as well as reduced leakage currents.

  14. Surface effects in the energy loss of ions passing through a thin foil

    SciTech Connect (OSTI)

    Osma, J.

    1997-09-01

    The role of surface plasmon excitation in the interaction of ions passing through thin films has been studied in both the Bloch hydrodynamic approximation and the local response approach for projectile velocities above the maximum of the stopping power curve. The effect of the surface is found to be much weaker when the dispersion of the modes is taken into consideration than in the case of nondispersive media, though qualitatively the main features of the hydrodynamic approach resemble those of the local one. A generalization of the Bothe-Landau convolution formula for the loss probability distribution is derived to take into account the scattering due to the surface. The effects of the surface in the energy-loss spectra are discussed. A comparison with experiment is given. {copyright} {ital 1997} {ital The American Physical Society}

  15. Single pass electron beam cooling of gold ions between EBIS LINAC and booster is theoretically possible!

    SciTech Connect (OSTI)

    Hershcovitch, A.

    2011-01-01

    Electron beam cooling is examined as an option to reduce momentum of gold ions exiting the EBIS LINAC before injection into the booster. Electron beam parameters are based on experimental data (obtained at BNL) of electron beams extracted from a plasma cathode. Many issues, regarding a low energy high current electron beam that is needed for electron beam cooling to reduce momentum of gold ions exiting the EBIS LINAC before injection into the booster, were examined. Computations and some experimental data indicate that none of these issues is a show stopper. Preliminary calculations indicate that single pass cooling is feasible; momentum spread can be reduced by more than an order of magnitude in about one meter. Hence, this option cooling deserves further more serious considerations.

  16. A new maximum-likelihood change estimator for two-pass SAR coherent change detection

    DOE PAGES-Beta [OSTI]

    Wahl, Daniel E.; Yocky, David A.; Jakowatz, Jr., Charles V.; Simonson, Katherine Mary

    2016-01-11

    In past research, two-pass repeat-geometry synthetic aperture radar (SAR) coherent change detection (CCD) predominantly utilized the sample degree of coherence as a measure of the temporal change occurring between two complex-valued image collects. Previous coherence-based CCD approaches tend to show temporal change when there is none in areas of the image that have a low clutter-to-noise power ratio. Instead of employing the sample coherence magnitude as a change metric, in this paper, we derive a new maximum-likelihood (ML) temporal change estimate—the complex reflectance change detection (CRCD) metric to be used for SAR coherent temporal change detection. The new CRCD estimatormore » is a surprisingly simple expression, easy to implement, and optimal in the ML sense. As a result, this new estimate produces improved results in the coherent pair collects that we have tested.« less

  17. Miniature low-pass filter in low-loss 9k7 LTCC

    DOE PAGES-Beta [OSTI]

    Dai, Steve Xunhu; Hsieh, Lung -Hwa

    2015-09-30

    DuPont 9k7 low-temperature cofired ceramic (LTCC) is a low-loss, or high-quality-factor Q, tape system targeting at radio frequency (RF) applications. This paper reports on the effect of a critical process parameter, the heating rate, on the densification and dielectric properties of the 9k7 LTCC. The role of competing densification and crystallization during the sintering of 9k7 is discussed. The high Q of DuPont 9K7 can be used to improve RF system performance, for example a better receiver noise figure, by designing embedded passive RF components such as inductors, capacitors and filters. Furthermore, miniaturized multilayer low-pass filters (LPF) with a widemore » stopband were fabricated to showcase the technology.« less

  18. Intrinsic low pass filtering improves signal-to-noise ratio in critical-point flexure biosensors

    SciTech Connect (OSTI)

    Jain, Ankit; Alam, Muhammad Ashraful

    2014-08-25

    A flexure biosensor consists of a suspended beam and a fixed bottom electrode. The adsorption of the target biomolecules on the beam changes its stiffness and results in change of beam's deflection. It is now well established that the sensitivity of sensor is maximized close to the pull-in instability point, where effective stiffness of the beam vanishes. The question: Do the signal-to-noise ratio (SNR) and the limit-of-detection (LOD) also improve close to the instability point?, however remains unanswered. In this article, we systematically analyze the noise response to evaluate SNR and establish LOD of critical-point flexure sensors. We find that a flexure sensor acts like an effective low pass filter close to the instability point due to its relatively small resonance frequency, and rejects high frequency noise, leading to improved SNR and LOD. We believe that our conclusions should establish the uniqueness and the technological relevance of critical-point biosensors.

  19. Understanding barotrauma in fish passing hydro structures: a global strategy for sustainable development of water resources

    SciTech Connect (OSTI)

    Brown, Richard S.; Colotelo, Alison HA; Pflugrath, Brett D.; Boys, Craig A.; Baumgartner, Lee J.; Deng, Zhiqun; Silva, Luiz G.; Brauner, Colin J.; Mallen-Cooper, Martin; Phonekhampeng, Oudom; Thorncraft, Garry; Singhanouvong, Douangkham

    2014-03-24

    Freshwater fishes are one of the most imperiled groups of vertebrates and species declines have been linked to a number of anthropogenic influences. This is alarming as the diversity and stability of populations are at risk. In addition, freshwater fish serve as important protein sources, particularly in developing countries. One of the focal activities thought to influence freshwater fish population declines is water resource development, which is anticipated to increase over the next several decades. For fish encountering hydro structures, such as passing through hydroturbines, there may be a rapid decrease in pressure which can lead to injuries commonly referred to as barotraumas. The authors summarize the research to date that has examined the effects of rapid pressure changes on fish and outline the most important factors to consider (i.e., swim bladder morphology, depth of acclimation, migration pattern and life stage) when examining the susceptibility of barotraumas for fish of interest.

  20. STRUCTURAL CONTROLS OF THE EMERSON PASS GEOTHERMAL SYSTEM, NORTHWESTERN NEVADA: CHARACTERIZATION OF A "BLIND" SYSTEM

    SciTech Connect (OSTI)

    Anderson, Ryan B; Faulds, James E

    2013-10-27

    The Pyramid Lake area is favorable for geothermal development due to the tectonic setting of the region. The Walker Lane belt, a dextral shear zone that accommodates ~20% relative motion between the Pacific and North American plates, terminates northwestward in northeast California. NW-directed dextral shear is transferred to WNW extension accommodated by N-to -NNE striking normal faults of the Basin and Range. As a consequence, enhanced dilation occurs on favorably oriented faults generating high geothermal potential in the northwestern Great Basin. The NW-striking right-lateral Pyramid Lake fault, a major structure of the northern Walker Lane, terminates at the southern end of Pyramid Lake and transfers strain to the NNE-striking down to the west Lake Range fault, resulting in high geothermal potential. Known geothermal systems in the area have not been developed due to cultural considerations of the Pyramid Lake Paiute Tribe. Therefore, exploration has been focused on discovering blind geothermal systems elsewhere on the reservation by identifying structurally favorable settings and indicators of past geothermal activity. One promising area is the northeast end of Pyramid Lake, where a broad left step between the west-dipping range-bounding faults of the Lake and Fox Ranges has led to the formation of a broad, faulted relay ramp. Furthermore, tufa mounds, mineralized veins, and altered Miocene rocks occur proximal to a thermal anomaly discovered by a 2-m shallow temperature survey at the north end of the step-over in Emerson Pass. Detailed geologic mapping has revealed a system of mainly NNE-striking down to the west normal faults. However, there are three notable exceptions to this generality, including 1) a prominent NW-striking apparent right-lateral fault, 2) a NW-striking down to the south fault which juxtaposes the base of the mid-Miocene Pyramid sequence against younger late Tertiary sedimentary rocks, and 3) a NNE-striking down to the east normal fault