National Library of Energy BETA

Sample records for georgia athens ga

  1. 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.

  2. Georgia - Compare - U.S. Energy Information Administration (EIA)

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

    Georgia Georgia

  3. Georgia - Rankings - U.S. Energy Information Administration (EIA)

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

    Georgia Georgia

  4. Georgia - Search - U.S. Energy Information Administration (EIA)

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

    Georgia Georgia

  5. SREL Reprint #3188

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

    School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA 2Department of Environmental Health Science, University of Georgia, Athens, GA 30602,...

  6. Athens, Ohio: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Registered Research Institutions in Athens, Ohio Ohio University Voinovich School of Leadership and Public Affairs Registered Energy Companies in Athens, Ohio American...

  7. Dalton, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Georgia: Energy Resources (Redirected from Dalton, GA) Jump to: navigation, search Equivalent URI DBpedia Coordinates 34.7698021, -84.9702228 Show Map Loading map......

  8. Workplace Charging Challenge Partner: Georgia Institute of Technology...

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

    Joined the Challenge: February 2014 Headquarters: Atlanta, GA Charging Location: Atlanta, GA Domestic Employees: 6,490 Georgia Institute of Technology is a leader in innovation and ...

  9. Categorical Exclusion Determinations: Georgia | Department of Energy

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

    Georgia Categorical Exclusion Determinations: Georgia Location Categorical Exclusion Determinations issued for actions in Georgia. DOCUMENTS AVAILABLE FOR DOWNLOAD May 2, 2016 CX-100596 Categorical Exclusion Determination Energy Savings Performance Contract (ESPC) at Marine Corps Logistics Base Albany (MCLBA), GA - Biomass Steam Turbine Generator Award Number: DE-EE0007461 CX(s) Applied: A9 Federal Energy Management Program Date: 04/13/2016 Location(s): GA Office(s): Golden Field Office March 4,

  10. ,"Georgia Natural Gas Industrial Price (Dollars per Thousand...

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

    586-8800",,,"1292016 12:15:32 AM" "Back to Contents","Data 1: Georgia Natural Gas Industrial Price (Dollars per Thousand Cubic Feet)" "Sourcekey","N3035GA3" "Date","Georgia...

  11. In Savannah, Georgia, Even the Data is Green | Department of...

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

    In Savannah, Georgia, Even the Data is Green In Savannah, Georgia, Even the Data is Green May 5, 2011 - 4:49pm Addthis The new energy efficient IT Data Center in Savannah, GA. | ...

  12. Newton County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    in Newton County, Georgia Covington, Georgia Mansfield, Georgia Newborn, Georgia Oxford, Georgia Porterdale, Georgia Social Circle, Georgia Retrieved from "http:...

  13. Chatham County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    County, Georgia Bloomingdale, Georgia Garden City, Georgia Georgetown, Georgia Isle of Hope, Georgia Montgomery, Georgia Pooler, Georgia Port Wentworth, Georgia Savannah, Georgia...

  14. Liberty County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    A. Places in Liberty County, Georgia Allenhurst, Georgia Flemington, Georgia Fort Stewart, Georgia Gumbranch, Georgia Hinesville, Georgia Midway, Georgia Riceboro, Georgia...

  15. SREL Reprint #3172

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

    School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA 2Savannah River Ecology Laboratory, University of Georgia, Drawer E, Aiken, SC 29802,...

  16. SREL Reprint #3120

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

    1Department of Environmental Health Science, University of Georgia, Athens, GA 30602, USA 2Savannah River Ecology Laboratory, University of Georgia, Drawer E, Aiken, SC 29802,...

  17. Carbohydrate and lignin are simultaneously solubilized from unpretreat...

    Office of Scientific and Technical Information (OSTI)

    University of Georgia, Athens, GA Georgia Institute of Technology ORNL North Carolina State University National Renewable Energy Laboratory (NREL) National Energy Renewable ...

  18. EECBG Success Story: In Savannah, Georgia, Even the Data is Green...

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

    The new energy efficient IT Data Center in Savannah, Georgia. | Courtesy of the City of Savannah, GA. The new energy efficient IT Data Center in Savannah, Georgia. | Courtesy of ...

  19. Cherokee County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Ball Ground, Georgia Canton, Georgia Holly Springs, Georgia Mountain Park, Georgia Nelson, Georgia Waleska, Georgia Woodstock, Georgia Retrieved from "http:en.openei.orgw...

  20. Madison County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Number 3 Climate Zone Subtype A. Places in Madison County, Georgia Carlton, Georgia Colbert, Georgia Comer, Georgia Danielsville, Georgia Hull, Georgia Ila, Georgia Royston,...

  1. Walton County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Number 3 Climate Zone Subtype A. Places in Walton County, Georgia Between, Georgia Good Hope, Georgia Jersey, Georgia Loganville, Georgia Monroe, Georgia Social Circle, Georgia...

  2. Rabun County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Places in Rabun County, Georgia Clayton, Georgia Dillard, Georgia Mountain City, Georgia Sky Valley, Georgia Tallulah Falls, Georgia Tiger, Georgia Retrieved from "http:...

  3. Gwinnett County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    BJ Gas Recovery Biomass Facility Places in Gwinnett County, Georgia Auburn, Georgia Berkeley Lake, Georgia Braselton, Georgia Buford, Georgia Dacula, Georgia Duluth, Georgia...

  4. Georgia State Historic Preservation Programmatic Agreement | Department of

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

    Energy Georgia State Historic Preservation Programmatic Agreement Georgia State Historic Preservation Programmatic Agreement Fully executed programmatic agreement between DOE, State Energy Office and State Historic Preservation Office. state_historic_preservation_programmatic_agreement_ga.pdf (1.06 MB) More Documents & Publications Arizona State Historic Preservation Programmatic Agreement Delaware State Historic Preservation Programmatic Agreement Florida State Historic Preservation

  5. City of Hampton, Georgia (Utility Company) | Open Energy Information

    Open Energy Info (EERE)

    search Name: City of Hampton Place: Georgia Website: www.cityofhampton-ga.govservi Outage Hotline: 770-946-4306; after hours- 911 References: EIA Form EIA-861 Final Data...

  6. City of La Grange, Georgia (Utility Company) | Open Energy Information

    Open Energy Info (EERE)

    to: navigation, search Name: City of La Grange Place: Georgia Phone Number: 706-883-2030 Website: www.lagrange-ga.orgUtilities. Outage Hotline: 706-883-2130 References: EIA...

  7. Hart County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Number 3 Climate Zone Subtype A. Places in Hart County, Georgia Bowersville, Georgia Canon, Georgia Hartwell, Georgia Reed Creek, Georgia Royston, Georgia Retrieved from "http:...

  8. Houston County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    County, Georgia Byron, Georgia Centerville, Georgia Perry, Georgia Robins AFB, Georgia Warner Robins, Georgia Retrieved from "http:en.openei.orgwindex.php?titleHoustonCounty,...

  9. Meriwether County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Climate Zone Number 3 Climate Zone Subtype A. Places in Meriwether County, Georgia Gay, Georgia Greenville, Georgia Haralson, Georgia Lone Oak, Georgia Luthersville, Georgia...

  10. Harris County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Harris County, Georgia Hamilton, Georgia Pine Mountain, Georgia Shiloh, Georgia Waverly Hall, Georgia West Point, Georgia Retrieved from "http:en.openei.orgw...

  11. Middle Georgia Biofuels | Open Energy Information

    Open Energy Info (EERE)

    Georgia Biofuels Jump to: navigation, search Name: Middle Georgia Biofuels Place: East Dublin, Georgia Zip: 31027 Product: Georgia-based biodiesel producer. References: Middle...

  12. Secretary Bodman Touts Importance of Cellulosic Ethanol at Georgia

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

    Biorefinery Groundbreaking | Department of Energy Touts Importance of Cellulosic Ethanol at Georgia Biorefinery Groundbreaking Secretary Bodman Touts Importance of Cellulosic Ethanol at Georgia Biorefinery Groundbreaking October 6, 2007 - 4:21pm Addthis SOPERTON, GA - U.S. Secretary of Energy Samuel W. Bodman today attended a groundbreaking ceremony for Range Fuels' biorefinery - one of the nation's first commercial-scale cellulosic ethanol biorefineries - and made the following statement.

  13. Franklin County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Climate Zone Number 4 Climate Zone Subtype A. Places in Franklin County, Georgia Canon, Georgia Carnesville, Georgia Franklin Springs, Georgia Gumlog, Georgia Lavonia,...

  14. Appling County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Georgia Appling County Pellets Places in Appling County, Georgia Baxley, Georgia Graham, Georgia Surrency, Georgia Retrieved from "http:en.openei.orgw...

  15. Peach County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    A. Places in Peach County, Georgia Byron, Georgia Fort Valley, Georgia Perry, Georgia Warner Robins, Georgia Retrieved from "http:en.openei.orgwindex.php?titlePeachCounty,G...

  16. Columbia County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Places in Columbia County, Georgia Evans, Georgia Grovetown, Georgia Harlem, Georgia Martinez, Georgia Retrieved from "http:en.openei.orgwindex.php?titleColumbiaCounty,Geor...

  17. Oconee County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Climate Zone Number 3 Climate Zone Subtype A. Places in Oconee County, Georgia Bishop, Georgia Bogart, Georgia North High Shoals, Georgia Watkinsville, Georgia Retrieved...

  18. Terrell County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Number 3 Climate Zone Subtype A. Places in Terrell County, Georgia Bronwood, Georgia Dawson, Georgia Parrott, Georgia Sasser, Georgia Retrieved from "http:en.openei.orgw...

  19. Upson County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Climate Zone Number 3 Climate Zone Subtype A. Places in Upson County, Georgia Hannahs Mill, Georgia Lincoln Park, Georgia Salem, Georgia Sunset Village, Georgia Thomaston,...

  20. fe0013961-GaTech | netl.doe.gov

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

  1. SREL Reprint #3047

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

    Department of Geology, The University of Georgia, Athens, GA 30602, USA 4Department of Chemistry and Earth Sciences, Dartmouth College, Hanover NH, USA Abstract: Despite the...

  2. SREL Reprint #3210

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

    & Environmental Sciences, University of Kentucky, Lexington, KY, USA 4Department of Microbiology, University of Georgia, Athens, GA, USA Abstract: Arkashin Schurf (Arkashin) and...

  3. BRMF Georgia Mountain Biofuels | Open Energy Information

    Open Energy Info (EERE)

    BRMF Georgia Mountain Biofuels Jump to: navigation, search Name: BRMFGeorgia Mountain Biofuels Place: Clayton, Georgia Product: Biodiesel plant developer in Georgia. References:...

  4. West Athens, California: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. West Athens is a census-designated place in Los Angeles County, California.1 References...

  5. Effingham County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Climate Zone Number 2 Climate Zone Subtype A. Places in Effingham County, Georgia Guyton, Georgia Rincon, Georgia Springfield, Georgia Retrieved from "http:en.openei.orgw...

  6. Pickens County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Number 4 Climate Zone Subtype A. Places in Pickens County, Georgia Jasper, Georgia Nelson, Georgia Talking Rock, Georgia Retrieved from "http:en.openei.orgw...

  7. Glascock County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Zone Subtype A. Places in Glascock County, Georgia Edge Hill, Georgia Gibson, Georgia Mitchell, Georgia Retrieved from "http:en.openei.orgwindex.php?titleGlascockCounty,Geor...

  8. Jones County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    in Jones County, Georgia Alterra Bioenergy LLC Places in Jones County, Georgia Gray, Georgia Macon, Georgia Retrieved from "http:en.openei.orgwindex.php?titleJonesCo...

  9. Butts County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Number 3 Climate Zone Subtype A. Places in Butts County, Georgia Flovilla, Georgia Jackson, Georgia Jenkinsburg, Georgia Retrieved from "http:en.openei.orgw...

  10. Whitfield County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Zone Subtype A. Registered Energy Companies in Whitfield County, Georgia Wilson and Dalton Places in Whitfield County, Georgia Cohutta, Georgia Dalton, Georgia Tunnel Hill,...

  11. Wayne County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Zone Number 2 Climate Zone Subtype A. Places in Wayne County, Georgia Jesup, Georgia Odum, Georgia Screven, Georgia Retrieved from "http:en.openei.orgwindex.php?titleWayne...

  12. SREL Reprint #3082

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

    1Savannah River Ecology Laboratory, University of Georgia, PO Drawer E, Aiken, SC 29802, USA 2Institute of Ecology, University of Georgia, Athens, GA 30602, USA 3Department of...

  13. SREL Reprint #3114

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

    1Savannah River Ecology Laboratory, University of Georgia, PO Drawer E, Aiken, SC 29802, USA 2Institute of Ecology, University of Georgia, Athens, GA 30602, USA 3Department of...

  14. Marietta, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Act Smart Grid Projects in Marietta, Georgia Cobb Electric Membership Corporation Smart Grid Project Registered Energy Companies in Marietta, Georgia Atlanta Chemical...

  15. Georgia/Incentives | Open Energy Information

    Open Energy Info (EERE)

    Local Loan Program Yes Atlanta Gas Light - Energy Efficiency Incentive Program (Georgia) Utility Rebate Program No Biomass Sales and Use Tax Exemption (Georgia) Sales Tax...

  16. Marion County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Climate Zone Number 3 Climate Zone Subtype A. Places in Marion County, Georgia Buena Vista, Georgia Retrieved from "http:en.openei.orgwindex.php?titleMarionCounty,Georgia...

  17. Sumter County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Number 3 Climate Zone Subtype A. Registered Energy Companies in Sumter County, Georgia Habitat for Humanity Places in Sumter County, Georgia Americus, Georgia Andersonville,...

  18. Bryan County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Number 2 Climate Zone Subtype A. Places in Bryan County, Georgia Pembroke, Georgia Richmond Hill, Georgia Retrieved from "http:en.openei.orgwindex.php?titleBryanCounty,Ge...

  19. Towns County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Number 4 Climate Zone Subtype A. Places in Towns County, Georgia Hiawassee, Georgia Young Harris, Georgia Retrieved from "http:en.openei.orgwindex.php?titleTownsCounty,G...

  20. Georgia's 8th congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    Georgia. Registered Energy Companies in Georgia's 8th congressional district Alterra Bioenergy Alterra Bioenergy LLC Biomass Energy Services Inc Middle Georgia Biofuels Retrieved...

  1. Georgia Regions | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    state, county, city, or district. For more information, please visit the Middle School Coach page. Georgia Region Middle School Regional Georgia Georgia Regional Middle School...

  2. Georgia Shore Assistance Act

    SciTech Connect (OSTI)

    Pendergrast, C.

    1984-01-01

    The Georgia General Assembly passed the Shore Assistance Act in 1979 in order to fill a regulatory gap in the state's management of its coastal resources. A review of its legislative history, purposes, applications, and effects in terms of the sand sharing system of sand dunes, beaches, sandbars, and shoals concludes that the Act is poorly drafted. In its application on the oceanfront, it betrays its intent and protects the oceanfront owner. It has failed to satisfy the requirements of the public trust in the tidal foreshore. Amendments to clarify its understanding of the functions and values of the sand-sharing system should also conform with the state's duties under the public trust. 139 references.

  3. Georgia Power | Open Energy Information

    Open Energy Info (EERE)

    An investor-owned utility that serves 2.25m customers in 155 counties of Georgia, USA. Coordinates: 33.748315, -84.391109 Show Map Loading map... "minzoom":false,"mappi...

  4. Georgia Power- Advanced Solar Initiative

    Broader source: Energy.gov [DOE]

    Note: According to Georgia Power's website, the Advanced Solar Initiative's final program guidelines are due to be published on June 25th and the bidding period for is expected to open on July 10,...

  5. Georgia Power- Solar Buyback Program

    Broader source: Energy.gov [DOE]

    Georgia Power, the state's largest utility, has established a green power program, that allows the company to purchase limited solar generation at a premium price based on other customers volunta...

  6. Camilla, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Map This article is a stub. You can help OpenEI by expanding it. Camilla is a city in Mitchell County, Georgia. It falls under Georgia's 2nd congressional district.12...

  7. Adrian, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    is a stub. You can help OpenEI by expanding it. Adrian is a city in Emanuel County and Johnson County, Georgia. It falls under Georgia's 12th congressional district.12...

  8. Alamo, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Map This article is a stub. You can help OpenEI by expanding it. Alamo is a town in Wheeler County, Georgia. It falls under Georgia's 1st congressional district.12...

  9. Chatsworth, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    This article is a stub. You can help OpenEI by expanding it. Chatsworth is a city in Murray County, Georgia. It falls under Georgia's 9th congressional district.12 Registered...

  10. Rome, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Rome is a city in Floyd County, Georgia. It falls under Georgia's 11st congressional district.12...

  11. Ailey, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Map This article is a stub. You can help OpenEI by expanding it. Ailey is a city in Montgomery County, Georgia. It falls under Georgia's 12th congressional district.12...

  12. Georgia Transmission Corp | Open Energy Information

    Open Energy Info (EERE)

    Corp Jump to: navigation, search Name: Georgia Transmission Corp Place: Georgia References: EIA Form EIA-861 Final Data File for 2010 - File1a1 EIA Form 861 Data Utility Id 7197...

  13. Georgia Nonprofit Helps Homeowners Save Energy

    Broader source: Energy.gov [DOE]

    Residents in Georgia are living in more comfortable and energy-efficient homes because of this Savannah based weatherization program.

  14. Georgia Nuclear Profile - Power Plants

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

    nuclear power plants, summer capacity and net generation, 2010" "Plant name/total reactors","Summer capacity (mw)","Net generation (thousand mwh)","Share of State nuclear net generation (percent)","Owner" "Edwin I Hatch Unit 1, Unit 2","1,759","13,902",41.5,"Georgia Power Co" "Vogtle Unit 1, Unit 2","2,302","19,610",58.5,"Georgia Power Co" "2 Plants 4

  15. Lighting Up Georgia Convenience Stores

    Office of Energy Efficiency and Renewable Energy (EERE)

    Thanks to help from the Energy Department, convenience stores across Georgia are saving energy by switching to energy efficient lighting. In the first year alone, participating small businesses have saved over $7,000 after the retrofits and over 54,000 KWh of energy.

  16. SREL Reprint #3096

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

    Radiation Ecology I. L. Brisbin Jr. and C. E. Dallas University of Georgia, Athens, GA, ... SREL Reprint 3096 Brisbin, I. L., Jr., and C. E. Dallas. 2008. Radiation Ecology. In: S. ...

  17. SREL Reprint #3193

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

    R. Hickman1,3, and Thomas M. Luhring1,4 1Savannah River Ecology Laboratory, Aiken, SC, USA 2Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA,...

  18. SREL Reprint #3112

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

    University of Georgia, Athens, GA 30602, USA 3Canadian Wildlife Service, 300-2365 Albert Street, Regina, Saskatchewan, Canada S4P 4K1 4Department of Biology, University of...

  19. SREL Reprint #3169

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

    of Georgia, Athens, GA 30602, USA 2Department of Biological Sciences, University of New Hampshire, 46 College Road, Durham, NH 03824, USA 3Warnell School of Forestry and Natural ...

  20. Thermophilic lignocellulose deconstruction (Journal Article)...

    Office of Scientific and Technical Information (OSTI)

    North Carolina State University ORNL University of Georgia, Athens, GA Publication Date: 2013-01-01 OSTI Identifier: 1116489 DOE Contract Number: DE-AC05-00OR22725 Resource Type: ...

  1. Quick Facts | Department of Energy

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

    Contact Information Administrator: Kenneth E. Legg Headquarters: 1166 Athens Tech Road Elberton, GA 30635-6711 Telephone: 706-213-3800 FAX: 706-213-3884 Marketing Area Georgia, ...

  2. File:USDA-CE-Production-GIFmaps-GA.pdf | Open Energy Information

    Open Energy Info (EERE)

    GA.pdf Jump to: navigation, search File File history File usage Georgia Ethanol Plant Locations Size of this preview: 776 600 pixels. Full resolution (1,650 1,275 pixels,...

  3. Bacon County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    169-2006 Climate Zone Number 2 Climate Zone Subtype A. Places in Bacon County, Georgia Alma, Georgia Retrieved from "http:en.openei.orgwindex.php?titleBaconCounty,Georgia&o...

  4. McDuffie County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Number 3 Climate Zone Subtype A. Places in McDuffie County, Georgia Dearing, Georgia Thomson, Georgia Retrieved from "http:en.openei.orgwindex.php?titleMcDuffieCounty,Geor...

  5. Recovery Act State Memos Georgia

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

    Georgia For questions about DOE's Recovery Act activities, please contact the DOE Recovery Act Clearinghouse: 1-888-DOE-RCVY (888-363-7289), Monday through Friday, 9 a.m. to 7 p.m. Eastern Time https://recoveryclearinghouse.energy.gov/contactUs.htm. All numbers and projects listed as of June 1, 2010 TABLE OF CONTENTS RECOVERY ACT SNAPSHOT................................................................................... 1 FUNDING ALLOCATION

  6. Americus, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    2nd congressional district.12 Registered Energy Companies in Americus, Georgia Habitat for Humanity References US Census Bureau Incorporated place and minor civil...

  7. ,"Georgia Natural Gas LNG Storage Withdrawals (MMcf)"

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

    Of Series","Frequency","Latest Data for" ,"Data 1","Georgia Natural Gas LNG Storage Withdrawals (MMcf)",1,"Annual",2014 ,"Release Date:","9302015" ,"Next Release...

  8. ,"Georgia Natural Gas LNG Storage Additions (MMcf)"

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

    Of Series","Frequency","Latest Data for" ,"Data 1","Georgia Natural Gas LNG Storage Additions (MMcf)",1,"Annual",2014 ,"Release Date:","9302015" ,"Next Release...

  9. Georgia/Wind Resources | Open Energy Information

    Open Energy Info (EERE)

    Guidebook >> Georgia Wind Resources WindTurbine-icon.png Small Wind Guidebook * Introduction * First, How Can I Make My Home More Energy Efficient? * Is Wind Energy Practical...

  10. Georgia Power- Small Commercial Energy Efficiency Program

    Broader source: Energy.gov [DOE]

    Georgia Power offers Small Commercial rebates to customers on qualifying rates. See program web site for additional details including eligibility information.

  11. Atlanta, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Solarity Sustainable World Capital TCE Energy Corporation Waspa Wheego Electric Cars Energy Incentives for Atlanta, Georgia City of Atlanta - Sustainable Home Initiative in...

  12. GEORGIA RECOVERY ACT SNAPSHOT | Department of Energy

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

    Georgia has substantial natural resources, including biomass and hydroelectric power .The American Recovery & Reinvestment Act (ARRA) is making a meaningful down payment on the ...

  13. Chattahoochee Hill Country, Georgia: Energy Resources | Open...

    Open Energy Info (EERE)

    Hill Country, Georgia: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 31.721548, -83.2599068 Show Map Loading map... "minzoom":false,"mappings...

  14. Georgia (country): Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Country Profile Name Georgia Population Unavailable GDP Unavailable Energy Consumption 0.17 Quadrillion Btu 2-letter ISO code GE 3-letter ISO code GEO Numeric ISO...

  15. City of Hogansville, Georgia (Utility Company) | Open Energy...

    Open Energy Info (EERE)

    search Name: Hogansville City of Place: Georgia Website: www.cityofhogansville.org Facebook: https:www.facebook.comhogansville.georgia Outage Hotline: 706.637.6648...

  16. Georgia Tech School of Civil and Environmental Engineering |...

    Open Energy Info (EERE)

    School of Civil and Environmental Engineering Jump to: navigation, search Name: Georgia Tech School of Civil and Environmental Engineering Abbreviation: Georgia Tech School of CEE...

  17. Georgia Tech Center for Innovative Fuel Cell and Battery Technologies...

    Open Energy Info (EERE)

    Innovative Fuel Cell and Battery Technologies Jump to: navigation, search Name: Georgia Tech Center for Innovative Fuel Cell and Battery Technologies Place: Georgia Product: The...

  18. Secretary Bodman Touts Importance of Cellulosic Ethanol at Georgia...

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

    Secretary Bodman Touts Importance of Cellulosic Ethanol at Georgia Biorefinery Groundbreaking Secretary Bodman Touts Importance of Cellulosic Ethanol at Georgia Biorefinery...

  19. Energy Secretary to Visit Georgia Nuclear Reactor Site and Tennessee...

    Energy Savers [EERE]

    Chu will visit the Vogtle nuclear power plant in Waynesboro, Georgia, and Oak Ridge ... Secretary Chu traveled to Waynesboro, Georgia, to visit the Vogtle nuclear power plant, ...

  20. Hancock County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Climate Zone Number 3 Climate Zone Subtype A. Places in Hancock County, Georgia Sparta, Georgia Retrieved from "http:en.openei.orgwindex.php?titleHancockCounty,Georgi...

  1. City of Jackson, Georgia (Utility Company) | Open Energy Information

    Open Energy Info (EERE)

    Jackson, Georgia (Utility Company) Jump to: navigation, search Name: Jackson City of Place: Georgia Phone Number: 770-775-3858 Website: www.cityofjacksonga.com196El Facebook:...

  2. City of Adel, Georgia (Utility Company) | Open Energy Information

    Open Energy Info (EERE)

    Georgia (Utility Company) Jump to: navigation, search Name: City of Adel Place: Georgia Phone Number: (229) 896-3601 Website: www.cityofadel.usdepartments Outage Hotline: (229)...

  3. City of Lawrenceville, Georgia (Utility Company) | Open Energy...

    Open Energy Info (EERE)

    Georgia (Utility Company) Jump to: navigation, search Name: City of Lawrenceville Place: Georgia Phone Number: 770.963.2414 Website: www.lawrencevillega.orggovern Outage Hotline:...

  4. City of Oxford, Georgia (Utility Company) | Open Energy Information

    Open Energy Info (EERE)

    Oxford, Georgia (Utility Company) Jump to: navigation, search Name: Oxford City of Place: Georgia Phone Number: 770-786-7004 Website: www.oxfordgeorgia.org Outage Hotline:...

  5. Atkinson County, Georgia ASHRAE 169-2006 Climate Zone | Open...

    Open Energy Info (EERE)

    Atkinson County, Georgia ASHRAE 169-2006 Climate Zone Jump to: navigation, search County Climate Zone Place Atkinson County, Georgia ASHRAE Standard ASHRAE 169-2006 Climate Zone...

  6. Secretary Bodman Touts Importance of Cellulosic Ethanol at Georgia...

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

    Touts Importance of Cellulosic Ethanol at Georgia Biorefinery Groundbreaking Secretary Bodman Touts Importance of Cellulosic Ethanol at Georgia Biorefinery Groundbreaking October ...

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

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

    Georgia and Arkansas Residential Energy Code Field Studies Georgia and Arkansas Residential Energy Code Field Studies Lead Performer: Southeast Energy Efficiency Alliance - ...

  8. Alternative Fuels Data Center: Georgia Transportation Data for Alternative

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    Fuels and Vehicles Georgia Transportation Data for Alternative Fuels and Vehicles to someone by E-mail Share Alternative Fuels Data Center: Georgia Transportation Data for Alternative Fuels and Vehicles on Facebook Tweet about Alternative Fuels Data Center: Georgia Transportation Data for Alternative Fuels and Vehicles on Twitter Bookmark Alternative Fuels Data Center: Georgia Transportation Data for Alternative Fuels and Vehicles on Google Bookmark Alternative Fuels Data Center: Georgia

  9. SEP Success Story: Lighting Up Georgia Convenience Stores | Department of

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

    Energy Lighting Up Georgia Convenience Stores SEP Success Story: Lighting Up Georgia Convenience Stores March 28, 2012 - 2:23pm Addthis One of several Georgia convenience stores that improved lighting while saving energy and money. | Courtesy of Outlaw Consulting, Inc. One of several Georgia convenience stores that improved lighting while saving energy and money. | Courtesy of Outlaw Consulting, Inc. Convenience stores across Georgia are saving energy thanks to energy efficient lighting

  10. Energy Incentive Programs, Georgia | Department of Energy

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

    What load managementdemand response options are available to me? Georgia Power offers a set of real-time pricing programs. In one set of options under this service, customers are ...

  11. Georgia Power- Energy Efficiency Home Improvement Rebates

    Broader source: Energy.gov [DOE]

    Georgia Power offers up to $2,575 in rebates to customers who choose to improve home performance with whole building BPI certified efficiency measures or up to $700 for individual improvements from...

  12. Central Georgia EMC- Photovoltaic Rebate Program

    Broader source: Energy.gov [DOE]

    In June 2008, Central Georgia Electric Membership Corporation (CGEMC) began offering a rebate of $450 per kilowatt (kW) to residential members who install photovoltaic (PV) systems that are...

  13. Milton, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Milton is a city in Fulton County, Georgia.1 References US Census Bureau Incorporated...

  14. Fossil Energy | National Energy Technology Laboratory | Georgia...

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

    Engineering and an adjunct professor in the College of Computing and the Ernest J. Scheller College of Business. He served as a Vice President and Director of the Georgia Tech...

  15. Clean Cities: Clean Cities-Georgia

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

    Atlanta was designated as the first Clean Cities coalition in the nation at the Georgia Dome in 1993. Prior to being elected as the coalition's executive director, Francis served...

  16. Georgia's 2nd congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    Energy Companies in Georgia's 2nd congressional district First United Ethanol LLC Habitat for Humanity Retrieved from "http:en.openei.orgwindex.php?titleGeorgia%27s2ndc...

  17. Middle Georgia El Member Corp | Open Energy Information

    Open Energy Info (EERE)

    El Member Corp Place: Georgia Phone Number: 1-800-342-0144 Website: www.mgemc.com Facebook: https:www.facebook.comMiddleGeorgiaEMC Outage Hotline: 229-268-2671; 800-342-0144...

  18. Central Georgia El Member Corp | Open Energy Information

    Open Energy Info (EERE)

    Central Georgia El Member Corp Place: Georgia Phone Number: 770-775-7857 Website: www.cgemc.com Twitter: @CentralGAEMC Outage Hotline: 770-775-7857 References: EIA Form EIA-861...

  19. City of Commerce, Georgia (Utility Company) | Open Energy Information

    Open Energy Info (EERE)

    City of Commerce, Georgia (Utility Company) Jump to: navigation, search Name: City of Commerce Place: Georgia Phone Number: (706) 335-4200 Website: www.commercega.orgContentDef...

  20. North Georgia Elec Member Corp | Open Energy Information

    Open Energy Info (EERE)

    navigation, search Name: North Georgia Elec Member Corp Place: Georgia Phone Number: Dalton: (706) 259-9441; Fort Oglethorpe: (706) 866-2231; Calhoun: (706) 629-3160; Trion:...

  1. Ben Hill County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Climate Zone Number 3 Climate Zone Subtype A. Places in Ben Hill County, Georgia Fitzgerald, Georgia Retrieved from "http:en.openei.orgwindex.php?titleBenHillCounty,Geo...

  2. Pine Mountain, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    article is a stub. You can help OpenEI by expanding it. Pine Mountain is a town in Harris County and Meriwether County, Georgia. It falls under Georgia's 3rd congressional...

  3. McCaysville, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Act Smart Grid Projects in McCaysville, Georgia Tri State Electric Membership Corporation Smart Grid Project Utility Companies in McCaysville, Georgia Tri-State Electric Member...

  4. College Park, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. College Park is a city in Clayton County and Fulton County, Georgia. It falls under Georgia's 5th...

  5. Georgia Renewable Electric Power Industry Net Summer Capacity...

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

    Georgia" "Energy Source",2006,2007,2008,2009,2010 "Geothermal","-","-","-","-","-" "Hydro Conventional",2027,2032,2041,2046,2052 "Solar","-","-","-","-","-" "Wind","-","-","-","-",...

  6. Georgia Renewable Electric Power Industry Net Generation, by...

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

    Georgia" "Energy Source",2006,2007,2008,2009,2010 "Geothermal","-","-","-","-","-" "Hydro Conventional",2569,2236,2145,3260,3322 "Solar","-","-","-","-","-" "Wind","-","-","-","-",...

  7. 2014 Race to Zero Student Design Competition: Georgia Institute of

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

    Technology Profile | Department of Energy Georgia Institute of Technology Profile 2014 Race to Zero Student Design Competition: Georgia Institute of Technology Profile 2014 Race to Zero Student Design Competition: Georgia Institute of Technology Profile, from the U.S. Department of Energy. rtz_georgia_profile.pdf (4.02 MB) More Documents & Publications 2014 Race to Zero Student Design Competition: Auburn University Profile 2014 Race to Zero Student Design Competition: University of

  8. Water-supply potential of the Upper Floridan aquifer in the vicinity of Savannah, Georgia

    SciTech Connect (OSTI)

    Garza, R.; Krause, R.E. )

    1993-03-01

    The Upper Floridan aquifer is the primary source of freshwater in coastal Georgia. Groundwater withdrawal in the area of Savannah and in the adjacent coastal areas in Georgia and South Carolina has resulted in large regional water-level declines and a reversal of the hydraulic gradient that existed prior to development. Changes in gradient and decreasing water levels are causing lateral encroachment of seawater into the Upper Floridan aquifer at the northern end of Hilton Head Island, SC, and vertical intrusion of saltwater into the Upper and Lower Floridan aquifers in the Brunswick, GA., area. Concerns about future water-supply demands prompted the US Geological Survey and the Chatham County-Savannah Metropolitan Planning Commission to undertake a cooperative study to evaluate the ground-water resources in the Savannah, GA, area. A numerical ground-water flow model was developed and used in conjunction with other previously calibrated models in the coastal areas of Georgia and South Carolina to simulate the effects of additional ground-water withdrawal on water levels. Based on model simulations and the constraint of preventing additional water-level declines at the locations of encroachment and intrusion, the potential of the Upper Floridan aquifer to supply additional water in the Savannah area is limited under present hydrologic conditions. The potential for additional withdrawal in the vicinity of Savannah, GA, ranges from less than 1 million gallons per day (Mgal/d) to about 5 Mgal/d. Because of the limited water-supply potential, hypothetical alternatives of ground-water withdrawal were simulated to determine the effects on water levels. These simulations indicate that reduction and redistribution of ground-water withdrawal would not adversely affect water levels at the locations of encroachment and intrusion.

  9. CONSENT-BASED SITING PUBLIC MEETING Georgia Tech Hotel and Conference Center

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

    Georgia Tech Hotel and Conference Center 800 Spring Street N.W. Atlanta, GA 30308 April 11, 2016 FULL TRANSCRIPT Mr. Jim Hamilton. Good afternoon, and to those in earlier time zones via webinar, good morning. Welcome, and thank you all for being here today. My name is Jim Hamilton. I'm an advisor to the Department of Energy's Consent-Based Siting Team, and my role today is to help us all have an open and productive conversation. To start off we have a few housekeeping issues to go over, and I'll

  10. EA-1963: Elba Liquefaction Project, Savannah, Georgia

    Office of Energy Efficiency and Renewable Energy (EERE)

    The Federal Energy Regulatory Commission (FERC) is preparing, with DOE as a cooperating agency, an EA to analyze the potential environmental impacts of a proposal to add natural gas liquefaction and export capabilities at the existing Elba Liquefied Natural Gas Terminal near Savannah, Georgia. Additional information is available at FERCs eLibrary website, elibrary.ferc.gov/idmws/docket_search.asp; search for docket number PF13-3.

  11. City of Mansfield, Georgia (Utility Company) | Open Energy Information

    Open Energy Info (EERE)

    search Name: City of Mansfield Place: Georgia Website: www.mansfieldga.comutilities. Facebook: https:www.facebook.commansfieldga Outage Hotline: 770-710-8235 References: EIA...

  12. EA-1963: Elba Liquefaction Project, Savannah, Georgia | Department...

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

    Gas Terminal near Savannah, Georgia. Additional information is available at FERC's eLibrary website, elibrary.ferc.govidmwsdocketsearch.asp; search for docket number PF13-3....

  13. EECBG Success Story: Georgia County Turning Industrial and Farm...

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

    Georgia County Turning Industrial and Farm Waste Into Big Energy Savings EECBG Success ... Learn more. Addthis Related Articles EECBG Success Story: County Aims to Save with ...

  14. Georgia-UNEP Risoe Technology Needs Assessment Program | Open...

    Open Energy Info (EERE)

    UNEP Risoe Technology Needs Assessment Program Jump to: navigation, search Name Georgia-UNEP Risoe-Technology Needs Assessment Program AgencyCompany Organization UNEP-Risoe...

  15. Building America Case Study: Savannah Gardens, Savannah, Georgia...

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

    Savannah Gardens Savannah, Georgia PROJECT INFORMATION Construction: New home Type: Single-family, affordable Partners: Savannah Housing Department Chatham Home Builders Southface ...

  16. Georgia Department of Natural Resources (GDNR) | Open Energy...

    Open Energy Info (EERE)

    References Retrieved from "http:en.openei.orgwindex.php?titleGeorgiaDepartmentofNaturalResources(GDNR)&oldid765343" Categories: Organizations Oil and Gas State Oil and...

  17. Stone Mountain, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Stone Mountain, Georgia: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 33.8081608, -84.170196 Show Map Loading map... "minzoom":false,"mappin...

  18. Sandy Springs, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Springs, Georgia: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 33.9242688, -84.3785379 Show Map Loading map... "minzoom":false,"mappingservi...

  19. Georgia's 9th congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    Resource Solutions ECO Solutions LLC Greenleaf Environmental Solutions Wilson and Dalton Utility Companies in Georgia's 9th congressional district Tri-State Electric Member...

  20. Atkinson County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Atkinson County, Georgia: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 31.2932161, -82.8640623 Show Map Loading map... "minzoom":false,"mapp...

  1. Georgia's 6th congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    Grid Project Registered Energy Companies in Georgia's 6th congressional district Atlanta Chemical Engineering LLC Cellnet Legacy Environmental Solutions Prenova Inc formerly...

  2. Georgia's 11th congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    Grid Project Registered Energy Companies in Georgia's 11th congressional district Atlanta Chemical Engineering LLC Prenova Inc formerly Service Resources Inc Sriya Innovations Inc...

  3. Georgia's 13th congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    Grid Project Registered Energy Companies in Georgia's 13th congressional district Atlanta Chemical Engineering LLC Prenova Inc formerly Service Resources Inc Sriya Innovations Inc...

  4. Cobb County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Smart Grid Project Registered Energy Companies in Cobb County, Georgia Atlanta Chemical Engineering LLC H I Solutions Inc Prenova Inc formerly Service Resources Inc...

  5. Polk County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Polk County, Georgia: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 34.0132398, -85.1479364 Show Map Loading map... "minzoom":false,"mappings...

  6. Washington County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Washington County, Georgia: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 32.962702, -82.820974 Show Map Loading map... "minzoom":false,"mapp...

  7. Pierce County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Pierce County, Georgia: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 31.343806, -82.1713632 Show Map Loading map... "minzoom":false,"mapping...

  8. Barrow County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Barrow County, Georgia: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 34.0142667, -83.6986568 Show Map Loading map... "minzoom":false,"mappin...

  9. Sakis Meliopoulos, Georgia Institute of Technology, PSERC webinar...

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

    Professor School of Electrical and Computer Engineering Georgia Institute of ... and ElectroMagnetic Interference) computer code, and the mGrid computer code - a ...

  10. QER SECOND INSTALLMENT PUBLIC MEETING-ATLANTA, GEORGIA | Department of

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

    Energy ATLANTA, GEORGIA QER SECOND INSTALLMENT PUBLIC MEETING-ATLANTA, GEORGIA MEETING DATE AND LOCATION Tuesday, May 24, 2016 Doors open: 9:00 AM; Program begins: 10:00 AM Georgia Tech GTRI Conference Center 250 14th Street, NW Atlanta, Georgia 30318 Watch the May 24th Atlanta meeting here. MEETING INFORMATION The Quadrennial Energy Review Task Force will host a public stakeholder meeting on the second installment of the Quadrennial Energy Review (QER), an integrated study of the U.S.

  11. Georgia's 4th congressional district: Energy Resources | Open...

    Open Energy Info (EERE)

    Vega Biofuels Inc formerly Vega Promotional Systems Retrieved from "http:en.openei.orgwindex.php?titleGeorgia%27s4thcongressionaldistrict&oldid1854...

  12. Georgia Green Loans Save & Sustain Program | Department of Energy

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

    technologies not identified Program Info Sector Name Non-Profit Administrator Georgia Green Loans Website http:www.georgiagreenloans.org Funding Source U.S. Small Business...

  13. Dawson County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Dawson County, Georgia: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 34.412912, -84.1435136 Show Map Loading map... "minzoom":false,"mapping...

  14. Hall County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hall County, Georgia: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 34.30778, -83.804868 Show Map Loading map... "minzoom":false,"mappingserv...

  15. Georgia Recovery Act State Memo | Department of Energy

    Energy Savers [EERE]

    Georgia has substantial natural resources, including biomass and hydroelectric power. The American Recovery & Reinvestment Act (ARRA) is making a meaningful down payment on the ...

  16. Clay County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Georgia: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 31.6447931, -85.0025539 Show Map Loading map... "minzoom":false,"mappingservice":"goog...

  17. Irwin County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Irwin County, Georgia: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 31.5893221, -83.2934086 Show Map Loading map... "minzoom":false,"mapping...

  18. ,"Georgia Natural Gas Vehicle Fuel Price (Dollars per Thousand...

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

    Of Series","Frequency","Latest Data for" ,"Data 1","Georgia Natural Gas Vehicle Fuel Price (Dollars per Thousand Cubic Feet)",1,"Annual",2012 ,"Release...

  19. ,"Georgia Natural Gas Imports Price All Countries (Dollars per...

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

    Of Series","Frequency","Latest Data for" ,"Data 1","Georgia Natural Gas Imports Price All Countries (Dollars per Thousand Cubic Feet)",1,"Annual",2014...

  20. Georgia-World Bank Climate Projects | Open Energy Information

    Open Energy Info (EERE)

    Projects Jump to: navigation, search Name Georgia-World Bank Climate Projects AgencyCompany Organization World Bank Focus Area Renewable Energy, Hydro Topics Background analysis...

  1. Mountain Park, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Park, Georgia: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 33.8442715, -84.1293605 Show Map Loading map... "minzoom":false,"mappingservice"...

  2. Gresham Park, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Gresham Park, Georgia: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 33.7034405, -84.3143682 Show Map Loading map... "minzoom":false,"mapping...

  3. Belvedere Park, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Belvedere Park, Georgia: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 32.4606984, -84.9040969 Show Map Loading map... "minzoom":false,"mappi...

  4. Environmental radionuclide distribution in Georgia after the Chernobyl accident

    SciTech Connect (OSTI)

    Mosulishvili, L.M.; Shoniya, N.I.; Katamadze, N.M.

    1994-01-01

    Atmospheric Chernobyl-released radioactivity, assessed at about 2 x 10{sup 18} Bq, caused global environmental contamination. Contaminated air masses appeared in the Transcaucasian region in early May, 1986. Rains that month promoted intense radionuclide deposition all over Georgia. The contamination level of western Georgia considerably exceeded the contamination level of eastern Georgia. The Black Sea coast of Georgia suffered from the Chernobyl accident as much as did strongly contaminated areas of the Ukraine and Belarus`. Unfortunately, governmental decrees on countermeasures against the consequences of the Chernobyl accident at that time did not even refer to the coast of Georgia. The authors observed the first increase in radioactivity background in rainfall samples collected on May 2, 1986, in Tbilisi. {gamma}-Spectrometric measurements of aerosol filters, vegetation, food stuffs, and other objects, in addition to rainfall, persistently confirmed the occurrence of short-lived radionuclides, including {sup 131}I. At first, this fact seemed unbelievable, because the Chernobyl accident had occurred only 4-5 days earlier and far from Georgia. However, these arguments proved to be faulty. Soon, environmental monitoring of radiation in Georgia became urgent. Environmental radionuclide distribution in Georgia shortly after the Chernobyl accident, as well as the methods of analysis, are reported in this paper.

  5. Georgia Number of Natural Gas Consumers

    Gasoline and Diesel Fuel Update (EIA)

    Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2010 78 70 78 75 78 75 78 78 75 78 75 78 2011 93 84 93 90 93 90 93 93 90 93 90 93 2012 93 87 93 90 93 90 93 93 90 93 90 93 2013 85 77 85 82 85 82 85 85 82 85 82 85 2014 99 90 99 96 99 96 99 99 96 99 96 99 2015 105 95 105 102 105 92 99 99 96 99 96 99 2016 111 100 111 107 102 99

    Vehicle Fuel Price (Dollars per Thousand Cubic Feet) Georgia Natural Gas Vehicle Fuel Price (Dollars per Thousand Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3

  6. Georgia Total Electric Power Industry Net Generation, by Energy...

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

    Georgia" "Energy Source",2006,2007,2008,2009,2010 "Fossil",100299,107165,99661,90634,97823 " Coal",86504,90298,85491,69478,73298 " Petroleum",834,788,742,650,641 " Natural ...

  7. ,"Georgia Natural Gas Price Sold to Electric Power Consumers...

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

    ,,"(202) 586-8800",,,"1292016 12:16:48 AM" "Back to Contents","Data 1: Georgia Natural Gas Price Sold to Electric Power Consumers (Dollars per Thousand Cubic Feet)"...

  8. Mitchell County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Mitchell County is a county in Georgia. Its FIPS County Code is 205. It is classified as...

  9. Jackson County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Jackson County is a county in Georgia. Its FIPS County Code is 157. It is classified as...

  10. Johnson County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Johnson County is a county in Georgia. Its FIPS County Code is 167. It is classified as...

  11. Richmond County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Richmond County is a county in Georgia. Its FIPS County Code is 245. It is classified as...

  12. Henry County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Henry County is a county in Georgia. Its FIPS County Code is 151. It is classified as ASHRAE...

  13. Miller County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Miller County is a county in Georgia. Its FIPS County Code is 201. It is classified as ASHRAE...

  14. Wheeler County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Wheeler County is a county in Georgia. Its FIPS County Code is 309. It is classified as...

  15. Stewart County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Stewart County is a county in Georgia. Its FIPS County Code is 259. It is classified as...

  16. Lee County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Lee County is a county in Georgia. Its FIPS County Code is 177. It is classified as ASHRAE...

  17. Murray County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Murray County is a county in Georgia. Its FIPS County Code is 213. It is classified as ASHRAE...

  18. Tift County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Its FIPS County Code is 277. It is classified as ASHRAE 169-2006 Climate Zone Number 3 Climate Zone Subtype A. Registered Energy Companies in Tift County, Georgia Biomass...

  19. Floyd County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Floyd County is a county in Georgia. Its FIPS County Code is 115. It is classified as ASHRAE...

  20. White County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. White County is a county in Georgia. Its FIPS County Code is 311. It is classified as ASHRAE...

  1. Montgomery County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Montgomery County is a county in Georgia. Its FIPS County Code is 209. It is classified as...

  2. Pike County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Pike County is a county in Georgia. Its FIPS County Code is 231. It is classified as ASHRAE...

  3. City of Palmetto, Georgia (Utility Company) | Open Energy Information

    Open Energy Info (EERE)

    Place: Georgia Phone Number: (770) 463-3322 Website: citypalmetto.comindex.aspx?ni Outage Hotline: (770) 463-3322 References: EIA Form EIA-861 Final Data File for 2010 -...

  4. FUPWG Meeting Agenda - Jekyll Island, Georgia | Department of...

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

    FUPWG Meeting Agenda - Jekyll Island, Georgia Logo for the FUPWG Spring 2012 meeting showing a crane, a lake, and wind turbines. The logo reads: Preserving our future with energy ...

  5. Georgia Total Electric Power Industry Net Summer Capacity, by...

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

    Georgia" "Energy Source",2006,2007,2008,2009,2010 "Fossil",28238,28096,28078,28103,28087 " Coal",13438,13275,13256,13211,13230 " Petroleum",2182,2169,2187,2188,2189 " Natural ...

  6. Webster County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Webster County is a county in Georgia. Its FIPS County Code is 307. It is classified as...

  7. Taylor County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Taylor County is a county in Georgia. Its FIPS County Code is 269. It is classified as ASHRAE...

  8. Evans County, Georgia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Evans County is a county in Georgia. Its FIPS County Code is 109. It is classified as ASHRAE...

  9. Central Georgia EMC- Residential Energy Efficiency Rebate Program

    Broader source: Energy.gov [DOE]

    Central Georgia Electric Member Corporation (CGEMC) offers rebates for residential customers to increase the energy efficiency of existing homes or to build new energy efficient homes.  This year,...

  10. Georgia Tech's Rohatgi Wins Second Annual Rappaport Award - News Releases |

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

    NREL Georgia Tech's Rohatgi Wins Second Annual Rappaport Award December 10, 2003 Golden, Colo. - The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) has presented the 2003 Paul Rappaport Renewable Energy and Energy Efficiency Award to Ajeet Rohatgi, founding director of the University Center of Excellence for Photovoltaics Research and Education at the Georgia Institute of Technology. "Dr. Rohatgi has for more than a quarter century focused his immense technical

  11. Bacon County, Georgia ASHRAE 169-2006 Climate Zone | Open Energy...

    Open Energy Info (EERE)

    Bacon County, Georgia ASHRAE 169-2006 Climate Zone Jump to: navigation, search County Climate Zone Place Bacon County, Georgia ASHRAE Standard ASHRAE 169-2006 Climate Zone Number...

  12. Barrow County, Georgia ASHRAE 169-2006 Climate Zone | Open Energy...

    Open Energy Info (EERE)

    Barrow County, Georgia ASHRAE 169-2006 Climate Zone Jump to: navigation, search County Climate Zone Place Barrow County, Georgia ASHRAE Standard ASHRAE 169-2006 Climate Zone Number...

  13. Ben Hill County, Georgia ASHRAE 169-2006 Climate Zone | Open...

    Open Energy Info (EERE)

    Ben Hill County, Georgia ASHRAE 169-2006 Climate Zone Jump to: navigation, search County Climate Zone Place Ben Hill County, Georgia ASHRAE Standard ASHRAE 169-2006 Climate Zone...

  14. SREL Reprint #3106

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

    6 Ecology of Chicken Turtles (Deirochelys reticularia) in a Seasonal Wetland Ecosystem: Exploiting Resource and Refuge Environments Kurt A. Buhlmann1,2, Justin D. Congdon1, J.Whitfield Gibbons1, and Judith L. Greene1 1University of Georgia, Savannah River Ecology Laboratory, Drawer E, Aiken, SC, 29802 USA 2University of Georgia, Odum School of Ecology, Athens, GA, 30602 USA Abstract: Chicken turtles (Deirochelys reticularia) were studied at Dry Bay, a Carolina bay wetland in South Carolina, USA,

  15. SREL Reprint #3127

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

    7 Development and characterization of twelve polymorphic microsatellite loci in the threatened Red Hills salamander, Phaeognathus hubrichti Stacey L. Lance1,2, Cris Hagen2, Travis C. Glenn1, Joseph J. Apodaca3, and Leslie J. Rissler3 1Department of Environmental Health Science, University of Georgia, Athens, GA 30602, USA 2Savannah River Ecology Laboratory, University of Georgia, Drawer E, Aiken, SC 29802, USA 3Department of Biological Sciences, University of Alabama, Tuscaloosa, AL 35487, USA

  16. SREL Reprint #3143

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

    3 Bacterial tolerances to metals and antibiotics in metal-contaminated and reference streams Meredith S. Wright1,2, Gretchen Loeffler Peltier2, Ramunas Stepanauskas3, and J Vaun McArthur1 1University of Georgia, Savannah River Ecology Laboratory, Aiken, SC, USA 2University of Georgia, Institute of Ecology, Athens, GA, USA 3Bigelow Laboratory for Ocean Sciences, West Boothbay Harbor, ME, USA Abstract: Anthropogenic-derived sources of selection are typically implicated as mechanisms for

  17. SREL Reprint #3165

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

    5 Microsatellites isolated from the North American ground skink (Scincella lateralis) Nathan D. Jackson1, Travis C. Glenn2,3, Cris Hagen2, Stacey L. Lance2, and Christopher C. Austin1 1Museum of Natural Science and Department of Biological Sciences, Louisiana State University, 119 Foster Hall, Baton Rouge, LA 70803, USA 2Savannah River Ecology Laboratory, University of Georgia, P.O. Drawer E, Aiken, SC 29802, USA 3Department of Environmental Health Science, University of Georgia, Athens, GA

  18. SREL Reprint #3352

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

    2 Hepatic and renal trace element concentrations in American alligators (Alligator mississippiensis) following chronic dietary exposure to coal fly ash contaiminated prey Tracey D. Tuberville1, David E. Scott1, Brian S. Metts1, John W. Finger Jr.1,2, and Matthew T. Hamilton1,3 1Savannah River Ecology Laboratory, University of Georgia, Aiken, SC 29802, USA 2Department of Environmental Health Science, University of Georgia, Athens, GA 30602, USA 3Warnell School of Forestry and Natural Resources,

  19. SREL Reprint #3362

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

    2 Spatial and temporal patterns of radiocesium contamination in mosquitofish, Gambusia holbrooki (Girard, 1859), inhabiting a nuclear reactor cooling reservoir Kevin A. Holloman1, Cham E. Dallas1, I. Lehr Brisbin, Jr2, and Charles H. Jagoe2 1Department of Pharmacology and Toxicology, College of Pharmacy, University of Georgia, Athens, GA 30602, USA 2Savannah River Ecology Laboratory, University of Georgia, P.O. Drawer E, Aiken, SC 29801, USA Abstract: Whole body concentrations of radiocesium

  20. Wood energy in Georgia: a five-year progress report

    SciTech Connect (OSTI)

    Not Available

    1982-01-01

    An increasing number of industrial plants and public and residential facilities in Georgia are using wood, Georgia's greatest renewable energy source, to replace gas, oil, coal, and electricity. All wood systems described in this report are or will soon be in operation in schools, prisons, hospitals, and other state facilities, and are producing substantial financial savings. The economic values from increased markets and jobs are important in all areas of the state, with total benefits projected at $2.9 million a year for state taxpayers. 2 figures.

  1. Georgia Natural Gas Underground Storage Withdrawals (Million Cubic Feet)

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

    Withdrawals (Million Cubic Feet) Georgia Natural Gas Underground Storage Withdrawals (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1970's 33 27 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 8/31/2016 Next Release Date: 9/30/2016 Referring Pages: Withdrawals of Natural Gas from Underground Storage - All Operators Georgia Underground Natural Gas Storage -

  2. Alternative Fuels Data Center: Georgia Sets the Pace for Plug-In Electric

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    Vehicles Georgia Sets the Pace for Plug-In Electric Vehicles to someone by E-mail Share Alternative Fuels Data Center: Georgia Sets the Pace for Plug-In Electric Vehicles on Facebook Tweet about Alternative Fuels Data Center: Georgia Sets the Pace for Plug-In Electric Vehicles on Twitter Bookmark Alternative Fuels Data Center: Georgia Sets the Pace for Plug-In Electric Vehicles on Google Bookmark Alternative Fuels Data Center: Georgia Sets the Pace for Plug-In Electric Vehicles on Delicious

  3. Energy Department Selects Three Bioenergy Research Centers for...

    Office of Environmental Management (EM)

    ... Laboratory in Golden, Colorado; University of Georgia in Athens, Georgia; Dartmouth College in Hanover, New Hampshire; and the University of Tennessee, in Knoxville, Tennessee. ...

  4. US SoAtl GA Site Consumption

    Gasoline and Diesel Fuel Update (EIA)

    household averages. * Per household electricity consumption in Georgia is among the highest in ... CONSUMPTION BY END USE Georgia is one of the few states where at least 30% of ...

  5. Sandia, Georgia Institute of Technology Form Academic Collaboration

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

    Georgia Institute of Technology Form Academic Collaboration - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense

  6. sorbent-georgia-tech | netl.doe.gov

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

    Rapid Temperature Swing Adsorption Using Polymer/Supported Amine Composite Hollow Fibers Project No.: DE-FE0007804 Georgia Tech Research Corporation is developing, fabricating, and testing a novel supported amine carbon dioxide (CO2) capture module at the bench scale. The module consists of hollow fibers loaded with supported adsorbents specifically adapted for the purpose of CO2 capture. Two key innovations are embodied in the design: (1) the fiber is highly loaded with the solid adsorbent to

  7. SREL Reprint #3325

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

    5 Exposure to mercury and Aroclor 1268 congeners in least terns (Sternula antillarum) in coastal Georgia, USA Gabrielle L. Robinson1,2, Gary L. Mills3, Angela H. Lindell3, Sara H. Schweitzer4, and Sonia M. Hernandez1,5 1Warnell School of Natural Resources, University of Georgia, 180 E. Green St., Athens, GA, USA 2Cape Cod National Seashore, 99 Marconi Site Rd, Wellfleet, MA 3University of Georgia Savannah River Ecology Laboratory, PO Drawer E, Aiken, SC, USA 4North Carolina Wildlife Resources

  8. 6,"Edwin I Hatch","Nuclear","Georgia Power Co",1759 7,"Thomas...

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

    Power Co",1793 6,"Edwin I Hatch","Nuclear","Georgia Power Co",1759 7,"Thomas A Smith Energy Facility","Natural gas","Oglethorpe Power Corporation",1290 ...

  9. Registration Open for National Environmental Justice Advisory Council (NEJAC) Public Meeting, September 11-12, 2013, Atlanta, Georgia

    Broader source: Energy.gov [DOE]

    Registration Open for National Environmental Justice Advisory Council (NEJAC) Public Meeting, September 11-12, 2013, Atlanta, Georgia.

  10. Georgia Natural Gas Input Supplemental Fuels (Million Cubic Feet)

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

    Input Supplemental Fuels (Million Cubic Feet) Georgia Natural Gas Input Supplemental Fuels (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1960's 0 0 0 1970's 0 0 0 0 0 0 0 0 0 0 1980's 24 57 151 84 28 121 124 248 241 292 1990's 209 185 166 199 123 130 94 14 16 12 2000's 73 51 7 14 5 0 3 2 52 2010's 732 701 660 642 635 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data.

  11. Georgia Natural Gas Underground Storage Injections All Operators (Million

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

    Cubic Feet) Underground Storage Injections All Operators (Million Cubic Feet) Georgia Natural Gas Underground Storage Injections All Operators (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1970's 123 366 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 8/31/2016 Next Release Date: 9/30/2016 Referring Pages: Injections of Natural Gas into Underground

  12. Georgia Natural Gas Underground Storage Net Withdrawals All Operators

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

    (Million Cubic Feet) Net Withdrawals All Operators (Million Cubic Feet) Georgia Natural Gas Underground Storage Net Withdrawals All Operators (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1970's -90 -339 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 8/31/2016 Next Release Date: 9/30/2016 Referring Pages: Net Withdrawals of Natural Gas from

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

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

    Federal Blue Ribbon Commission J. David Jameson Atlanta, GA October 18, 2011 Good Morning. I am David Jameson. I am President and CEO of the Greater Aiken, South Carolina, Chamber of Commerce. I am here today in my capacity as current Chairman of the SRS Community Reuse Organization. The SRSCRO is a non-profit regional group supporting economic diversification and job creation in a five-county in Georgia and South Carolina near the Department of Energy's Savannah River Site. We are unique among

  14. Georgia Natural Gas LNG Storage Net Withdrawals (Million Cubic Feet)

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

    Net Withdrawals (Million Cubic Feet) Georgia Natural Gas LNG Storage Net Withdrawals (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1980's 534 -1,598 -1,359 -169 -203 -525 596 149 545 343 1990's 1,345 390 16 -42 -94 -1,464 -189 -153 -698 -1,403 2000's -1,126 6,210 2,397 -2,138 -1,052 -1,436 -5,737 1,323 2,481 1,972 2010's 379 2,542 1,378 1,205 3,085 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure

  15. Georgia Natural Gas Vehicle Fuel Consumption (Million Cubic Feet)

    Gasoline and Diesel Fuel Update (EIA)

    Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1990's 17,054 33,351 32,505 2000's 42,034 34,666 56,588 32,258 45,926 72,267 95,407 121,726 96,316 142,467 2010's 175,082 196,492 308,096 279,506 289,783 354,090 Feet)

    Price All Countries (Dollars per Thousand Cubic Feet) Georgia Natural Gas Imports Price All Countries (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 1990's -- 2000's -- 1.92

  16. Georgia Natural Gas LNG Storage Additions (Million Cubic Feet)

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

    Additions (Million Cubic Feet) Georgia Natural Gas LNG Storage Additions (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1980's 20,484 1,508 1,555 1,024 678 1,834 1,942 1,150 1,702 2,930 1990's 2,779 1,969 1,573 1,855 3,788 3,746 6,523 3,221 1,760 607 2000's 3,241 6,772 3,426 5,422 5,570 5,971 7,705 2,817 4,372 3,182 2010's 2,693 3,306 2,097 1,385 7,130 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid

  17. Georgia Natural Gas LNG Storage Withdrawals (Million Cubic Feet)

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

    Withdrawals (Million Cubic Feet) Georgia Natural Gas LNG Storage Withdrawals (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1980's 19,950 3,106 2,914 1,193 881 2,359 1,346 1,001 1,157 2,586 1990's 1,435 1,579 1,557 1,896 3,881 5,210 6,712 3,374 2,458 2,010 2000's 4,367 562 1,029 3,283 4,518 4,535 1,968 1,493 1,891 1,210 2010's 2,314 764 719 180 4,046 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure

  18. Georgia Natural Gas Number of Commercial Consumers (Number of Elements)

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

    Commercial Consumers (Number of Elements) Georgia Natural Gas Number of Commercial Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1980's 94 98,809 102,277 106,690 1990's 108,295 109,659 111,423 114,889 117,980 120,122 123,200 123,367 126,050 225,020 2000's 128,275 130,373 128,233 129,867 128,923 128,389 127,843 127,832 126,804 127,347 2010's 124,759 123,454 121,243 126,060 122,573 - = No Data Reported; -- = Not Applicable; NA = Not

  19. Georgia Natural Gas Number of Industrial Consumers (Number of Elements)

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

    Industrial Consumers (Number of Elements) Georgia Natural Gas Number of Industrial Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1980's 3 3,034 3,144 3,079 1990's 3,153 3,124 3,186 3,302 3,277 3,261 3,310 3,310 3,262 5,580 2000's 3,294 3,330 3,219 3,326 3,161 3,543 3,053 2,913 2,890 2,254 2010's 2,174 2,184 2,112 2,242 2,481 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual

  20. Georgia Natural Gas Number of Residential Consumers (Number of Elements)

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

    Residential Consumers (Number of Elements) Georgia Natural Gas Number of Residential Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1980's 1,190 1,237,201 1,275,128 1,308,972 1990's 1,334,935 1,363,723 1,396,860 1,430,626 1,460,141 1,495,992 1,538,458 1,553,948 1,659,730 1,732,865 2000's 1,680,749 1,737,850 1,735,063 1,747,017 1,752,346 1,773,121 1,726,239 1,793,650 1,791,256 1,744,934 2010's 1,740,587 1,740,006 1,739,543 1,805,425

  1. Georgia Natural Gas Pipeline and Distribution Use (Million Cubic Feet)

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

    (Million Cubic Feet) Georgia Natural Gas Pipeline and Distribution Use (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1990's 7,973 7,606 8,846 2000's 5,636 7,411 7,979 7,268 6,235 5,708 6,092 5,188 5,986 6,717 2010's 8,473 10,432 10,509 7,973 6,977 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 8/31/2016 Next Release Date: 9/30/2016 Referring Pages:

  2. Georgia Natural Gas Total Consumption (Million Cubic Feet)

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

    Total Consumption (Million Cubic Feet) Georgia Natural Gas Total Consumption (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1990's 371,376 368,579 337,576 2000's 413,845 351,109 383,546 379,761 394,986 412,560 420,469 441,107 425,043 462,799 2010's 530,030 522,897 615,771 625,283 652,230 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 8/31/2016 Next Release

  3. sRecovery Act: Geologic Characterization of the South Georgia Rift Basin for Source Proximal CO2 Storage

    SciTech Connect (OSTI)

    Waddell, Michael

    2014-09-30

    the J/TR section based on neutron log porosity values. The only zones in Rizer #1 that appear to be porous were fractured diabase units where saline formation water was flowing into the borehole. Two geocellular models were created for the SC and GA study area. Flow simulation modeling was performed on the SC data set. The injection simulation used the newly acquired basin data as well as the Petrel 3-D geologic model that included geologic structure. Due to the new basin findings as a result of the newly acquired data, during phase two of the modeling the diabase unit was used as reservoir and the sandstone units were used as caprock. Conclusion are: 1) the SGR basin is composed of numerous sub-basins, 2) this study only looked at portions of two sub-basins, 3) in SC, 30 million tonnes of CO2 can be injected into the diabase units if the fracture network is continuous through the units, 4) due to the severity of the faulting there is no way of assuring the injected CO2 will not migrate upward into the overlying Coastal Plain aquifers, 5) in Georgia there appears to porous zones in the J/TR sandstones, 6) as in SC there is faulting in the sub-basin and the seismic suggest the faulting extends upward into the Coastal Plain making that area not suitable for CO2 sequestration, 7) the complex faulting observed at both study areas appear to be associated with transfer fault zones (Heffner 2013), if sub-basins in the Georgia portion of the SGR basin can be located that are far away from the transfer fault zones there is a strong possibility of sequestering CO2 in these areas, and 9) the SGR basin covers area in three states and this project only studied two small areas so there is enormous potential for CO2 sequestration in other portions the basin and further research needs to be done to find these areas.

  4. Wind Powering America: A New Wind Economy for South Carolina and Georgia Final Report

    SciTech Connect (OSTI)

    SC Energy Office: Southern Alliance for Clean Energy

    2013-02-12

    This report describes all activities undertaken by the Southern Alliance for Clean Energy (SACE) in cooperation with the states of Georgia and South Carolina to develop a public outreach program, including shared analytical and reference tools and other technical assistance.

  5. Cost-Effectiveness of ASHRAE Standard 90.1-2010 for the State of Georgia

    SciTech Connect (OSTI)

    Hart, Philip R.; Rosenberg, Michael I.; Xie, YuLong; Zhang, Jian; Richman, Eric E.; Elliott, Douglas B.; Loper, Susan A.; Myer, Michael

    2013-11-01

    Moving to the ANSI/ASHRAE/IES Standard 90.1-2010 version from the Base Code (90.1-2007) is cost-effective for all building types and climate zones in the State of Georgia.

  6. EA-1255: Project Partnership Transportation of Foreign-Owned Enriched Uranium from the Republic of Georgia

    Broader source: Energy.gov [DOE]

    This EA evaluates the environmental impacts for the proposal to transport 5.26 kilograms of enriched uranium-23 5 in the form of nuclear fuel, from the Republic of Georgia to the United Kingdom.

  7. EECBG Success Story: Georgia County Turning Industrial and Farm Waste Into Big Energy Savings

    Broader source: Energy.gov [DOE]

    Gwinnett County, Georgia built a "Gas to Energy" system at the city water resources center that will reduce operational costs and sanitary sewer overflows, thanks to an Energy Efficiency and Conservation Block Grant (EECBG). Learn more.

  8. Georgia County Turning Industrial and Farm Waste Into Big Energy Savings

    Office of Energy Efficiency and Renewable Energy (EERE)

    Thanks to a Department of Energy Recovery Act grant, Gwinnett County, Georgia is taking some of the grossest stuff on earth and turning it into some of the greenest stuff on earth.

  9. Georgia Regional High School Science Bowl | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Georgia Regional High School Science Bowl National Science Bowl® (NSB) NSB Home About Regional Competitions Rules, Forms, and Resources High School Regionals Middle School Regionals National Finals Volunteers Key Dates Frequently Asked Questions News Media Contact Us WDTS Home Contact Information National Science Bowl® U.S. Department of Energy SC-27/ Forrestal Building 1000 Independence Ave., SW Washington, DC 20585 E: Email Us High School Regionals Georgia Regional High School Science Bowl

  10. Georgia Regional Middle School Science Bowl | U.S. DOE Office of Science

    Office of Science (SC) Website

    (SC) Georgia Regional Middle School Science Bowl National Science Bowl® (NSB) NSB Home About Regional Competitions Rules, Forms, and Resources High School Regionals Middle School Regionals National Finals Volunteers Key Dates Frequently Asked Questions News Media Contact Us WDTS Home Contact Information National Science Bowl® U.S. Department of Energy SC-27/ Forrestal Building 1000 Independence Ave., SW Washington, DC 20585 E: Email Us Middle School Regionals Georgia Regional Middle School

  11. Microsoft Word - DOE-ID-12-028 Georgia Tech.doc

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

    8 SECTION A. Project Title: Nuclear Engineering and Science Equipment to Enhance Education and Research in Nuclear and Radiological Engineering at the Georgia Institute of Technology SECTION B. Project Description The Georgia Institute of Technology will address three areas with this project: -Enhancement in capabilities of an existing neutron generator through the addition of a pneumatic tube irradiation system, a shielded gamma spectrometry system, and glove box with additional barriers for

  12. SREL Reprint #3178

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

    8 Needles in haystacks: Estimating detection probability and occupancy of rare and cryptic snakes Andrew M. Durso, John D. Willson, and Christopher T. Winne Odum School of Ecology, University of Georgia, Athens, GA 30602, USA Savannah River Ecology Laboratory, Drawer E, Aiken, SC 29802, USA Abstract: The species most in need of conservation or management are often also the most difficult to monitor, because of their rarity, secretive habits, or both. To combat these challenges, presence/absence

  13. SREL Reprint #3281

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

    1 Mobilization of colloidal carbon during iron reduction in basaltic soils Shea W. Buettner1, Marc G. Kramer2, Oliver A. Chadwick3, and Aaron Thompson1 1Crop and Soil Sciences Department, University of Georgia, Athens, GA, USA 2Soil and Water Science Department, University of Florida, Gainesville, FL, USA 3Department of Geography, University of California, Santa Barbara, CA, USA Abstract: The transport of organic carbon (C) to deep mineral horizons in soils can lead to long-term C stabilization.

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

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

  15. SREL Reprint #3116

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

    6 Development and characterization of microsatellite loci in the American white pelican (Pelecanus erythrorhynchos) Caleb R. Hickman1, Maureen B. Peters1, Nicholas G. Crawford1, Cris Hagen1, Travis C. Glenn1,2, and Christopher M. Somers3 1Savannah River Ecology Laboratory, University of Georgia, Drawer E, Aiken, SC 29802, USA 2Department of Environmental Health Science, University of Georgia, Athens, GA 30602, USA 3Department of Biology, University of Regina, Regina, SK, Canada S4S 0A2 Abstract:

  16. SREL Reprint #3185

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

    5 Effects of Roads and Crabbing Pressures on Diamondback Terrapin Populations in Coastal Georgia Andrew M. Grosse1,2, John C. Maerz1, Jeffrey Hepinstall-Cymerman1, and Michael E. Dorcas3 1Daniel B. Warnell School of Forestry and Natural Resources, The University of Georgia, Athens, GA 30602, USA 2Savannah River Ecology Lab, Savannah River Site, Building 737-A, Drawer E, Aiken, SC 29802, USA 3Davidson College, Davidson, NC 28035, USA Abstract: Human activities, including the harvesting of natural

  17. SREL Reprint #3341

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

    1 Evaluating the effect of sample type on American alligator (Alligator mississippiensis) analyte values in a point-of-care blood analyser Matthew T. Hamilton1,2, John W. Finger Jr1,3, Megan E. Winzeler1, and Tracey D. Tuberville1 1Savannah River Ecology Laboratory, University of Georgia, Aiken, SC 29802, USA 2Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA 3Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA Abstract: The

  18. 16 April 2002

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

    Curriculum Vitae Updated: 14 December 2009 KURT A. BUHLMANN University of Georgia Odum School of Ecology Savannah River Ecology Laboratory Drawer E, Building 737-A Aiken, South Carolina 29802 803-725-5293 buhlmann@uga.edu kbuhlmann@earthlink.net EDUCATION AND DEGREES EARNED 1998-1999 Post-Doctoral Research Associate; Savannah River Ecology Laboratory, Aiken, SC 1993-1998 Ph.D. in Ecology, University of Georgia, Athens, GA 1990-1991 Graduate courses in Cave Biology and Biogeography, Old Dominion

  19. Energy conserving site design case study: Shenandoah, Georgia. Final report

    SciTech Connect (OSTI)

    Not Available

    1980-01-01

    The case study examines the means by which energy conservation can be achieved at an aggregate community level by using proper planning and analytical techniques for a new town, Shenandoah, Georgia, located twenty-five miles southwest of Atlanta's Hartsfield International Airport. A potentially implementable energy conservation community plan is achieved by a study team examining the land use options, siting characteristics of each building type, alternate infrastructure plans, possible decentralized energy options, and central utility schemes to determine how community energy conservation can be achieved by use of pre-construction planning. The concept for the development of mixed land uses as a passively sited, energy conserving community is based on a plan (Level 1 Plan) that uses the natural site characteristics, maximizes on passive energy siting requirement, and allows flexibility for the changing needs of the developers. The Level 2 Plan is identical with Level 1 plan plus a series of decentraized systems that have been added to the residential units: the single-family detached, the apartments, and the townhouses. Level 3 Plan is similar to the Level 1 Plan except that higher density dwellings have been moved to areas adjacent to central site. The total energy savings for each plan relative to the conventional plan are indicated. (MCW)

  20. Georgia Natural Gas % of Total Residential Deliveries (Percent)

    Gasoline and Diesel Fuel Update (EIA)

    Foot) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2013 1,014 1,015 1,016 1,015 1,014 1,015 1,016 1,019 1,017 1,016 1,017 1,017 2014 1,018 1,018 1,018 1,018 1,021 1,022 1,023 1,023 1,027 1,026 1,026 1,025 2015 1,025 1,026 1,025 1,026 1,028 1,031 1,030 1,028 1,029 1,028 1,026 1,027 2016 1,029 1,030 1,030 1,028 1,030 1,027

    % of Total Residential Deliveries (Percent) Georgia Natural Gas % of Total Residential Deliveries (Percent) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5

  1. Georgia Natural Gas Pipeline and Distribution Use Price (Dollars per

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

    Thousand Cubic Feet) Price (Dollars per Thousand Cubic Feet) Georgia Natural Gas Pipeline and Distribution Use 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 1960's 0.19 0.19 0.19 1970's 0.20 0.22 0.23 0.25 0.28 0.32 0.36 0.67 0.90 1.35 1980's 2.10 2.78 3.11 3.22 3.26 3.23 3.32 2.50 2.41 2.69 1990's 2.19 2.08 2.08 2.24 2.14 1.93 2.62 3.09 2.48 2.18 2000's 3.30 4.57 NA -- -- -- - = No Data Reported; -- = Not Applicable; NA

  2. Ecological investigation of a hazardous waste site, Warner Robins, Georgia

    SciTech Connect (OSTI)

    Wade, M.C. ); Billig, P. )

    1993-01-01

    Zone 1, Robins Air Force Base, Georgia, has been designated a National Priorities List Site by the US Environmental Protection Agency. The Remedial Investigation for Zone 1 recommended a quantitative analysis of ecological risk. To accomplish this task a characterization of the bottomland hardwood forest ecosystem present on the base was required. This ecological characterization included the study of hydrology, aquatic and wildlife biology, and wetlands ecology where potential impacts were in question. In addition, a suitable reference area was studied. The hydrologic investigation consisted primarily of the installation of water level recorders and staff gauges, collection of surface water data, installation of piezometers and collection of groundwater data, and the collection of rainfall data. The aquatic biology investigation centered around the sampling of benthic macroinvertebrate communities, bioassay toxicity tests for surface water and sediment, fish sampling, aquatic macrophyte collection, macrophyte collection, and emergent and free-floating plant collection. The wildlife biology investigation focused on a breeding bird survey. The wetlands ecology investigation comprised the collection of soil and vegetation samples and using the Wetland Evaluation Technique (WET) to assess the functions and values of the wetlands present.

  3. Ecological investigation of a hazardous waste site, Warner Robins, Georgia

    SciTech Connect (OSTI)

    Wade, M.; Billig, P.

    1993-05-01

    Landfill No. 4 and the sludge lagoon at Robins Air Force Base, Warner Robins, Georgia, were added to the United States Environmental Protection Agency (EPA) National Priorities List in 1987 because of highpotential for contaminant migration. Warner Robins is located approximately 90 miles southeast of Atlanta. In 1990 CH2M HILL conducted a Remedial Investigation at the base that recommended that further ecological assessment investigations be conducted (CH2M HILL 1990). The subject paper is the result of this recommendation. The ecological study was carried out by the Hazardous Waste Remedial Actions Program (HAZWRAP)Division of Martin Marietta Energy Systems, Inc., working jointly with its subcontractor CDM (CDM 1992a). The primary area of investigation (Zone 1) included the sludge lagoon, Landfill No. 4, the wetland area east of the landfill and west of Hannah Road (including two sewage treatment ponds), and the area between Hannah Road and Horse Creek (Fig. 1). The bottomland forest wetlands of Zone 1 extend from the landfill east to Horse Creek. Surface water and groundwater flow across Zone 1 is generally in an easterly direction toward Horse Creek. Horse Creek is a south-flowing tributary of the Ocmulgee River Floodplain. The objective of the study was to perform a quantitative analysis of ecological risk associated with the ecosystems present in Zone 1. This investigation was unique because the assessment was to be based upon many measurement endpoints resulting in both location-specific data and data that would assess the condition of the overall ecosystem. The study was segregated into five distinct field investigations: hydrology, surface water and sediment, aquatic biology, wetlands ecology, and wildlife biology.

  4. Sakis Meliopoulos, Georgia Institute of Technology, PSERC webinar, 2/16/2016

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

    Protection and Control of Systems with Converter Interfaced Generation Sakis Meliopoulos Georgia Power Distinguished Professor School of Electrical and Computer Engineering Georgia Institute of Technology sakis.m@gatech.edu PSERC Public Webinar February 16, 2016 2:00-3:00 p.m. Eastern Time (11:00-12:00 p.m. Pacific) If you plan to use the phone bridge, use the NEW number: 877-820-7831 (passcode: 965722#). Description: The protection of converter interfaced generation and associated circuits and

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

    Georgia Georgia

  6. 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.

  7. GA SNC Solar | Open Energy Information

    Open Energy Info (EERE)

    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...

  8. EA-1865: Department of Energy Loan Guarantee to Kior, Inc., for Biorefinery Facilities in Georgia, Mississippi, and Texas

    Broader source: Energy.gov [DOE]

    This EA will evaluate the environmental impacts of a proposal to issue a Federal loan guarantee to Kior, Inc., for biorefinery facilities in Georgia, Mississippi, and Texas. This EA is on hold.

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

    SciTech Connect (OSTI)

    Not Available

    2011-05-01

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

  10. Microsoft Word - DOE-ID-14-043 Georgia Institute of Tech. _1 EC B3-6.doc

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

    3 SECTION A. Project Title: Optimizing Polymer-Grafted Amidoxime-based Adsorbents for Uranium Uptake from Seawater - Georgia Institute of Technology SECTION B. Project Description Georgia Institute of Technology will conduct laboratory scale research on metal ion adsorption from aqueous solutions to provide a better understanding of the performance of amidoxime-grafted polymer fibers in uranium uptake from seawater through experiments and modeling. The objectives of the proposed work are to: 1.

  11. Microsoft Word - DOE-ID-14-044 Georgia Institute of Tech_3 EC B3-6.doc

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

    4 SECTION A. Project Title: Fundamental Study of Key Issues Related to Advanced S-CO2 Brayton Cycle: Prototypic HX Development and Cavitation - Georgia Institute of Technology SECTION B. Project Description Georgia Institute of Technology will perform research (integrated experimental, numerical and analytical work) that utilizes the existing facilities at the university to address the key scientific and operational issues pertinent to the compact heat exchanger systems and turbo-machinery. The

  12. Microsoft Word - DOE-ID-14-045 Georgia Institute of Tech. _2 EC B3-6.doc

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

    5 SECTION A. Project Title: Zeolite Membranes for Krypton/Xenon Separation from Spent Nuclear Fuel Reprocessing Off-Gas - Georgia Tech Research Corporation SECTION B. Project Description Georgia Tech Research Corporation will develop a novel, high-performance, low-energy intensity, lower-cost zeolite membrane process for Kr/Xe separation during spent nuclear fuel processing; and investigate the underlying molecular adsorption and transport processes in both 'idealized' and 'realistic' operating

  13. Control Center and Data Management Improvements Modernize Bulk Power Operations in Georgia

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

    Under the American Recovery and Reinvestment Act of 2009, the U.S. Department of Energy and the electricity industry have jointly invested over $7.9 billion in 99 cost- shared Smart Grid Investment Grant projects to modernize the electric grid, strengthen cybersecurity, improve interoperability, and collect an unprecedented level of data on smart grid and customer operations. 1. Summary Georgia System Operations Corporation's (GSOC) Smart Grid Investment Grant (SGIG) project modernized bulk

  14. 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.

  15. CX-005925: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Energy Efficiency and Conservation Block Grant - Georgia-City-Athens Clarke, Unified Government ofCX(s) Applied: A9, A11, B1.32, B2.5, B5.1Date: 05/13/2011Location(s): Athens-Clarke, GeorgiaOffice(s): Energy Efficiency and Renewable Energy

  16. CX-002777: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Georgia-City-Unified Government of Athens-ClarkeCX(s) Applied: B1.32, B2.5, A9, A11, B5.1Date: 06/17/2010Location(s): Athens, GeorgiaOffice(s): Energy Efficiency and Renewable Energy

  17. 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}.

  18. 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.

  19. 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.

  20. ,"Georgia Natural Gas Industrial Price (Dollars per Thousand Cubic Feet)"

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

    Price (Dollars per Thousand Cubic Feet)" ,"Click worksheet name or tab at bottom for data" ,"Worksheet Name","Description","# Of Series","Frequency","Latest Data for" ,"Data 1","Georgia Natural Gas Industrial Price (Dollars per Thousand Cubic Feet)",1,"Monthly","6/2016" ,"Release Date:","8/31/2016" ,"Next Release Date:","9/30/2016" ,"Excel File

  1. ,"Georgia Natural Gas LNG Storage Net Withdrawals (MMcf)"

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

    LNG Storage Net Withdrawals (MMcf)" ,"Click worksheet name or tab at bottom for data" ,"Worksheet Name","Description","# Of Series","Frequency","Latest Data for" ,"Data 1","Georgia Natural Gas LNG Storage Net Withdrawals (MMcf)",1,"Annual",2014 ,"Release Date:","8/31/2016" ,"Next Release Date:","9/30/2016" ,"Excel File

  2. ,"Georgia Natural Gas Vehicle Fuel Consumption (MMcf)"

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

    Vehicle Fuel Consumption (MMcf)" ,"Click worksheet name or tab at bottom for data" ,"Worksheet Name","Description","# Of Series","Frequency","Latest Data for" ,"Data 1","Georgia Natural Gas Vehicle Fuel Consumption (MMcf)",1,"Monthly","6/2016" ,"Release Date:","8/31/2016" ,"Next Release Date:","9/30/2016" ,"Excel File

  3. Appearance Results from MiniBooNE Georgia Karagiorgi Columbia University

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

    Appearance Results from MiniBooNE Georgia Karagiorgi Columbia University WIN'11 - Cape Town, South Africa 2 Outline of this talk: -- The LSND excess signal: Evidence for high-Δm 2 oscillations -- The MiniBooNE experiment -- MiniBooNE neutrino mode oscillation results: LSND signature refuted -- MiniBooNE antineutrino mode oscillation results: LSND signature confrmed ? -- Light sterile neutrino oscillations: Where we stand today -- Future searches: MiniBooNE, MicroBooNE 1993 -1998 1998 2001

  4. Superfund at work: Hazardous waste cleanup efforts nationwide, Spring 1993 (Powersville site profile, Peach County, Georgia)

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

    The US Environmental Protection Agency (EPA) encountered much more than a municipal landfill at the Powersville site in Peach County, Georgia. Contamination from improperly dumped hazardous wastes and pesticides tainted an old quarry used for household garbage. Chemicals migrating into area ground water threatened local drinking water supplies. To address these issues, EPA's Superfund program designed a cleanup strategy that included: negotiating with the county and chemical companies to contain the hazardous wastes on site underneath a protective cover; investigating reports of drinking water contamination and extending municipal water lines to affected residents; and conducting a tailored community relations program to inform and educate residents about the site.

  5. 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.

  6. Erin Abernethy | Savannah River Ecology Laboratory

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

    Erin Abernethy SREL Graduate Program Odum School of Ecology Erin Abernethy Masters Student Rhodes Lab Erin joined the Savannah River Ecology Lab in January 2013 as a Master’s student with Dr. Gene Rhodes through the Odum School of Ecology at the University of Georgia. Erin grew up in Aiken, SC, and is currently attending classes in Athens, Ga. She will be studying the scavenging ecology of invasive species in Hawai’i, as well as doing field and lab work at SREL. Before joining SREL, Erin lived

  7. EA-1963: Elba Liquefaction Project; Chatham, Hart, Jefferson, and Effingham Counties, Georgia, and Jasper County, South Carolina

    Broader source: Energy.gov [DOE]

    Federal Energy Regulatory Commission (FERC) prepared an EA that assesses the potential environmental impacts of a proposal to add natural gas liquefaction and export capabilities at the existing Elba Liquefied Natural Gas Terminal near Savannah, Georgia. Information about this project is available on the FERC website (www.ferc.gov).

  8. 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%.

  9. 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.

  10. 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.

  11. 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.

  12. Georgia Hosts Multi-Agency Waste Isolation Pilot Plant Transportation Exercise

    Broader source: Energy.gov [DOE]

    COVINGTON, Ga. – Emergency personnel throughout the U.S. who respond in the event of a potential accident involving radioactive waste shipments take part in mock training scenarios to help them prepare for an actual incident.

  13. 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.

  14. Georgia Natural Gas Delivered to Commercial Consumers for the Account of

    Gasoline and Diesel Fuel Update (EIA)

    Others (Million Cubic Feet) Delivered to Commercial Consumers for the Account of Others (Million Cubic Feet) Georgia Natural Gas Delivered to Commercial Consumers for the Account of Others (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1980's 1,067 3,418 5,176 1990's 5,721 6,395 6,389 5,487 4,304 3,663 3,646 6,211 9,078 16,996 2000's 48,726 40,531 38,395 39,611 44,025 42,112 38,204 38,967 41,555 43,845 2010's 49,157 46,512 42,971 46,494

  15. Georgia Natural Gas Imports Price All Countries (Dollars per Thousand Cubic

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

    Feet) Price All Countries (Dollars per Thousand Cubic Feet) Georgia Natural Gas Imports Price All Countries (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 1990's -- 2000's -- 1.92 3.51 5.12 6.47 9.18 7.03 6.79 9.71 3.73 2010's 4.39 4.20 2.78 3.36 4.33 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 8/31/2016 Next Release Date: 9/30/2016

  16. Georgia Natural Gas Vehicle Fuel Price (Dollars per Thousand Cubic Feet)

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

    Vehicle Fuel Price (Dollars per Thousand Cubic Feet) Georgia Natural Gas Vehicle Fuel 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 1990's 3.54 4.07 3.86 3.86 4.14 4.10 2000's -- -- 13.05 12.93 12.91 12.11 2010's 5.17 5.57 14.51 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 8/31/2016 Next Release Date: 9/30/2016 Referring Pages:

  17. 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: ...

  18. 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.

  19. (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.

  20. 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%.

  1. 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.

  2. Georgia-Pacific Palatka Plant Uses Thermal Pinch Analysis and Evaluates Water Reduction in Plant-Wide Energy Assessment

    SciTech Connect (OSTI)

    2002-12-01

    This OIT BestPractices Case Study describes the methods and results used in a plant-wide assessment at a Georgia-Pacific paper mill in Palatka, FL. Assessment personnel recommended several projects, which, if implemented, have the potential to save the plant more than 729,000 MMBtu per year and $2.9 million per year. In addition, the plant could reduce water use by 2,100 gallons per minute.

  3. Long-Term Need for New Nuclear Workers The SRS Community Reuse Organization (SRSCRO) Region of Georgia

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

    Long-Term Need for New Nuclear Workers The SRS Community Reuse Organization (SRSCRO) Region of Georgia and South Carolina has the most unique nuclear industry capabilities in the nation. This region is at the forefront of new nuclear power production, environmental stewardship, innovative technology and national security. In 2009, the SRSCRO commissioned a survey of eight area nuclear employers that concluded nearly 10,000 new workers will be needed in the next decade to support existing

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

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

    Needs and Opportunities from the 2011 Residential Energy Efficiency Stakeholders Meeting Atlanta, Georgia - March 16-18, 2011 May 2011 ii NOTICE This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information,

  5. 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.

  6. 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.

  7. 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: ...

  8. 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.

  9. 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.

  10. 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.

  11. Oxidation of ultrathin GaSe

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

    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.

  12. Chiyoda Thoroughbred CT-121 clean coal project at Georgia Power`s Plant Yates

    SciTech Connect (OSTI)

    Burford, D.P.

    1997-12-31

    The Chiyoda Thoroughbred CT-121 flue gas desulfurization (FGD) process at Georgia Power`s Plant Yates completed a two year demonstration of its capabilities in late 1994 under both high- and low-particulate loading conditions. This $43 million demonstration was co-funded by Southern Company, the Electric Power Research Institute and the DOE under the auspices of the US Department of Energy`s Round II Innovative Clean Coal Technology (ICCT) program. The focus of the Yates Project was to demonstrate several cost-saving modifications to Chiyoda`s already efficient CT-121 process. These modifications included: the extensive use of fiberglass reinforced plastics (FRP) in the construction of the scrubber vessel and other associated vessels, the elimination of flue gas reheat through the use of an FRP wet chimney, and reliable operation without a spare absorber module. This paper focuses on the testing results from the last trimester of the second phase of testing (high-ash loading). Specifically, operation under elevated ash loading conditions, the effects of low- and high-sulfur coal, air toxics verification testing results and unexpected improvements in byproduct gypsum quality are discussed.

  13. Pyrococcus Furiosus Genome Supplementary Data from the Adams Laboratory at the University of Georgia

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Adams, Michael W.W.; Weinberg, Michael V.; Schut, Gerrit J.; Brehm, Scott; Datta, Susmitta; Zhou, J.

    The research in the Adams Laboratory focuses on the physiology of hyperthermophilic organisms with an emphasis on metal-containing enzymes in the hyperthermophilic marine archaeon Pyrococcus furiosus. Three of the many articles from this University of Georgia lab have supplementary materials that are available on the Adams Lab website. All three sets of data are Open Reading Frames (ORFs) used for DNA microarray experiments and the changes in signal intensities. The full citations for the three articles are: 1) Weinberg, M. V., Schut, G. J., Brehm, S., Datta, S. and Adams, M. W. W. (2005) Cold shock of a hyperthermophilic archaeon: Pyrococcus furiosus exhibits multiple responses to a suboptimal growth temperature with a key role for membrane-bound glycoproteins. J Bacteriol. 187, 336-348; 2) Schut, G. J., Brehm, S. D., Datta, S. and Adams, M. W. W. (2003) "Whole genome DNA microarray analysis of a hyperthermophile and an archaeon: Pyrococcus furiosus grown on carbohydrates or peptides" J. Bacteriol. 185, 3935-3947; Schut, G. J., Zhou, J. and Adams, M. W. W. (2001) "DNA microarray analysis of the hyperthermophilic archaeon Pyrococcus furiosus evidence for a new type of sulfur-reducing enzyme" J. Bacteriol. 183, 7027-7036. Note that these articles are copyrighted by the Journal of Bacteriology.

  14. Health-hazard evaluation report HETA 86-469-2189, James River Corporation, Newnan, Georgia

    SciTech Connect (OSTI)

    Sinks, T.

    1992-03-01

    In response to a request from OSHA, a possible cancer cluster was investigated at the James River Corporation (SIC-2657), Newnan, Georgia. The paperboard packaging facility had been in operation for over 30 years. A retrospective cohort mortality study of 2050 workers employed at the facility between 1957 and 1988 was conducted. As of the study date, 141 workers were deceased, 1705 were alive, and 204 had been lost to follow-up. Overall mortality was similar to that expected as was mortality from diseases of the heart, accidents, and violence. The Standardized Mortality Ratios for all cancers was less than expected. Three workers with bladder cancer and six with kidney cancer were identified. No increased risk of bladder cancer was determined. The risk of kidney cancer was increased. The excess risk was associated with overall duration of employment but was not limited to any single department or work process. The author concludes that workers at the facility had an increased rate of kidney cancer. The author recommends measures to reduce exposures to inks containing pigments made from aromatic amines. Personal protective equipment should not be considered a substitute for adequate engineering controls. Follow-up on the cohort should continue.

  15. 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.

  16. 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.

  17. 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.

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

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

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

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. Structural Model of the Basement in the Central Savannah River Area, South Carolina and Georgia

    SciTech Connect (OSTI)

    Stephenson, D. [Westinghouse Savannah River Company, AIKEN, SC (United States); Stieve, A.

    1992-03-01

    Interpretation of several generations of seismic reflection data and potential field data suggests the presence of several crustal blocks within the basement beneath the Coastal Plain in the Central Savannah River Area (CSRA). The seismic reflection and refraction data include a grid of profiles that capture shallow and deep reflection events and traverse the Savannah River Site and vicinity. Potential field data includes aeromagnetic, ground magnetic surveys, reconnaissance and detailed gravity surveys. Subsurface data from recovered core are used to constrain the model.Interpretation of these data characteristically indicate a southeast dipping basement surface with some minor highs and lows suggesting an erosional pre-Cretaceous unconformity. This surface is interrupted by several basement faults, most of which offset only early Cretaceous sedimentary horizons overlying the erosional surface. The oldest fault is perhaps late Paleozoic because it is truncated at the basement/Coastal Plain interface. This fault is related in timing and mechanism to the underlying Augusta fault. The youngest faults deform Coastal Plain sediments of at least Priabonian age (40-36.6 Ma). One of these young faults is the Pen Branch faults, identified as the southeast dipping master fault for the Triassic Dunbarton basin. All the Cenozoic faults are probably related in time and mechanism to the nearby, well studied Belair fault.The study area thus contains a set of structures evolved from the Alleghanian orogeny through Mesozoic extension to Cenozoic readjustment of the crust. There is a metamorphosed crystalline terrane with several reflector/fault packages, a reactivated Triassic basin, a mafic terrane separating the Dunbarton basin from the large South Georgia basin to the southeast, and an overprint of reverse faults, some reactivated, and some newly formed.

  4. 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} ? cm{sup 2}, and a higher light output power compared to the reference light emitting diodes (LED) with semi-transparent p-contacts were measured in the tunnel junction LED (TJLED). A forward resistance of 5??10{sup ?4} ? cm{sup 2} was measured in a GaN PN junction with the identical tunnel junction contact as the TJLED, grown completely by MBE. The depletion region due to the impurities at the regrowth interface between the MBE tunnel junction and the MOCVD-grown LED was hence found to limit the forward resistance measured in the TJLED.

  5. ,"Georgia Natural Gas Price Sold to Electric Power Consumers (Dollars per Thousand Cubic Feet)"

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

    Price Sold to Electric Power Consumers (Dollars per Thousand Cubic Feet)" ,"Click worksheet name or tab at bottom for data" ,"Worksheet Name","Description","# Of Series","Frequency","Latest Data for" ,"Data 1","Georgia Natural Gas Price Sold to Electric Power Consumers (Dollars per Thousand Cubic Feet)",1,"Monthly","6/2016" ,"Release Date:","8/31/2016" ,"Next Release

  6. Economic Benefits, Carbon Dioxide (CO2) Emissions Reduction, and Water Conservation Benefits from 1,000 Megawatts (MW) of New Wind Power in Georgia (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2008-06-01

    The U.S. Department of Energy's Wind Powering America Program is committed to educating state-level policy makers and other stakeholders about the economic, CO2 emissions, and water conservation impacts of wind power. This analysis highlights the expected impacts of 1000 MW of wind power in Georgia. We forecast the cumulative economic benefits from 1000 MW of development in Georgia to be $2.1 billion, annual CO2 reductions are estimated at 3.0 million tons, and annual water savings are 1,628 million gallons.

  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. 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.

  9. 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.

  10. SREL Reprint #3321

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

    1 Effects of vegetation structure and artificial nesting habitats on hatchling sex determination and nest survival of Diamondback Terrapins Andrew M. Grosse1, Brian A. Crawford2, John C. Maerz2, Kurt A. Buhlmann1, Terry Norton3, Michelle Kaylor3, and Tracey D. Tuberville1 1Savannah River Ecology Laboratory, University of Georgia, Drawer E, Aiken, South Carolina 29802 2D. B. Warnell School of Forestry and Natural Resources, University of Georgia, Athens, Georgia 30602 3Georgia Sea Turtle Center,

  11. Transportation of foreign-owned enriched uranium from the Republic of Georgia. Environmental assessment for Project Partnership

    SciTech Connect (OSTI)

    1998-03-31

    The Department of Energy (DOE) Office of Nonproliferation and National Security (NN) has prepared a classified environmental assessment to evaluate the potential environmental impact for the transportation of 5.26 kilograms of enriched uranium-235 in the form of nuclear fuel, from the Republic of Georgia to the United Kingdom. The nuclear fuel consists of primarily fresh fuel, but also consists of a small quantity (less than 1 kilogram) of partially-spent fuel. Transportation of the enriched uranium fuel would occur via US Air Force military aircraft under the control of the Defense Department European Command (EUCOM). Actions taken in a sovereign nation (such as the Republic of Georgia and the United Kingdom) are not subject to analysis in the environmental assessment. However, because the action would involve the global commons of the Black Sea and the North Sea, the potential impact to the global commons has been analyzed. Because of the similarities in the two actions, the Project Sapphire Environmental Assessment was used as a basis for assessing the potential impacts of Project Partnership. However, because Project Partnership involves a small quantity of partially-spent fuel, additional analysis was conducted to assess the potential environmental impacts and to consider reasonable alternatives as required by NEPA. The Project Partnership Environmental Assessment found the potential environmental impacts to be well below those from Project Sapphire.

  12. 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.

  13. 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.

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

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

    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

  16. 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.

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

    SciTech Connect (OSTI)

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

    2013-12-04

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

  18. 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.

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

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

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

  20. 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.

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

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

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

    2011-01-01

    InGaN/GaN nanowire (NW) heterostructures grown by plasma assisted molecular beam epitaxy were studied in comparison to their GaN and InGaN counterparts. The InGaN/GaN heterostructure NWs are composed of a GaN NW, a thin InGaN shell, and a multifaceted InGaN cap wrapping the top part of the GaN NW. High-resolution transmission electron microscopy (HRTEM) images taken from different parts of a InGaN/GaN NW show a wurtzite structure of the GaN core and the epitaxial InGaN shell around it, while additional crystallographic domains are observed whithin the InGaN cap region. Large changes in the lattice parameter along the wire, from pure 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

  2. Public health assessment for Southwire Company and Southwire Company Copper Division, Carrollton, Carroll County, Georgia, Region 4: CERCLIS Number GAD003264421 and CERCLIS Number GAD000814541. Final report

    SciTech Connect (OSTI)

    1998-09-22

    The Southwire Company`s manufacturing divisions are located in Carroll County, Georgia, within the southeastern city limits of Carrollton. ATSDR identified contaminants, predominantly metals, in on-site soil, groundwater, surface water, sediment, fish and slag/waste material. On-site groundwater samples collected in 1984 indicated the presence of trichloroethylene (TCE).

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. Understanding cirrus ice crystal number variability for different...

    Office of Scientific and Technical Information (OSTI)

    Georgia Inst. of Technology, Atlanta, GA (United States) Univ. of Los Andes, Bogota (Colombia) NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States) Georgia Inst. ...

  13. 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.

  14. 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.

  15. 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.

  16. 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.

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

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

    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

  19. 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.

  20. 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.

  1. 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.

  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. 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.

  4. 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.

  5. 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.

  6. 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%.

  7. 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}.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. The design, construction, and monitoring of photovoltaic power system and solar thermal system on the Georgia Institute of Technology Aquatic Center. Volume 1

    SciTech Connect (OSTI)

    Long, R.C.

    1996-12-31

    This is a report on the feasibility study, design, and construction of a PV and solar thermal system for the Georgia Tech Aquatic Center. The topics of the report include a discussion of site selection and system selection, funding, design alternatives, PV module selection, final design, and project costs. Included are appendices describing the solar thermal system, the SAC entrance canopy PV mockup, and the PV feasibility study.

  19. Athens, Ohio: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Ohio American Hydrogen Corporation Carbon Cycle Engineering Dovetail Solar and Wind DuPont Electronic Technologies, Inc. Global Cooling Inc. Panich + Noel Architects Panich,...

  20. Athens, Greece: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    to: navigation, search Equivalent URI DBpedia GeoNames ID 264371 Coordinates 37.97918, 23.716647 Show Map Loading map... "minzoom":false,"mappingservice":"googlemaps3","type":...

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  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. 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.

  9. 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:...

  10. 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.

  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. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. Health assessment for Cedartown Industries, Cedartown, Polk County, Georgia, Region 4. CERCLIS No. GAD95840674. Preliminary report

    SciTech Connect (OSTI)

    Not Available

    1990-01-29

    The Cedartown Industries, Inc. site has been proposed for the National Priorities List (NPL) by the U.S. Environmental Protection Agency (EPA). The 7-acre site is located in Cedartown, Polk County, Georgia, in the northwest part of the State. In 1986, one sediment sample from an on-site impoundment and two soil samples (one background) were collected on-site and analyzed by EPD. Only Extraction Procedure (EP) Toxicity testing was performed on these samples. The test which measures the concentration of leachate generated from the soil showed leachate with lead concentrations up to 720 parts per million (ppm) and cadmium concentrations up to 1.4 ppm. Based on the information reviewed, ATSDR has concluded that the site is of potential public health concern because humans may be exposed to hazardous substances at concentrations that may result in adverse health effects. As noted in the Human Exposure Pathways Section above, human exposure to lead may occur via ingestion of, inhalation of, and dermal contact with surface water, sediments, soils, ground water, air, and food-chain entities.

  19. 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.

  20. 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.

  1. SREL Reprint #3364

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

    4 Blood and plasma biochemistry reference intervals for wild juvenile American alligators (Alligator mississippiensis) Matthew T. Hamilton1,2, Caitlin A. Kupar1,2, Meghan D. Kelley3, John W. Finger Jr.1,3, and Tracey D. Tuberville1 1Savannah River Ecology Laboratory, University of Georgia, PO Drawer E, Aiken, South Carolina 29802, USA 2Warnell School of Forestry and Natural Resources, University of Georgia, 180 E Green Street, Athens, Georgia 30602, USA 3Department of Biological Sciences, Auburn

  2. 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.}

  3. 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.

  4. SREL Reprint #3326

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

    6 Overwintering ecology of juvenile Gopher Tortoises (Gopherus polyphemus) Bess B. Harris1,2,5, Terry M. Norton3,4, Nathan P. Nibbelink2, and Tracey D. Tuberville1 1University of Georgia’s Savannah River Ecology Laboratory, Drawer E, Aiken, South Carolina 29802, USA 2Daniel B. Warnell School of Forestry and Natural Resources, 180 E Green Street, University of Georgia, Athens, Georgia 30602, USA 3Jekyll Island Authority’s Georgia Sea Turtle Center, 214 Stable Road, Jekyll Island, Georgia 31527,

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

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

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

    2009-01-01

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

  6. 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.

  7. 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.

  8. 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.

  9. 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.

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

    SciTech Connect (OSTI)

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

    2014-07-07

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

  11. 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.

  12. 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.

  13. 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.

  14. Thermal Design and Characterization of Heterogeneously Integrated InGaP/GaAs HBTs

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

    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

  15. 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.

  16. 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%.

  17. 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 ...

  18. 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 ...

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

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

    Confinement | Princeton Plasma Physics Lab 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 Spin on Understanding Plasma Confinement

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  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. 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.

  8. 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}.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Elba Island, GA Liquefied Natural Gas Imports from Qatar (Million...

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

    Liquefied Natural Gas Imports from Qatar (Million Cubic Feet) Elba Island, GA Liquefied Natural Gas Imports from Qatar (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep...

  14. Elba Island, GA Natural Gas Liquefied Natural Gas Imports from...

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

    Egypt (Million Cubic Feet) Elba Island, GA Natural Gas Liquefied Natural Gas Imports from Egypt (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2011 5,780 ...

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

    SciTech Connect (OSTI)

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

    2013-11-14

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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. Characterization of Cu(In,Ga)Se2 (CIGS) films with varying gallium ratios

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

    Claypoole, Jesse; Peace, Bernadette; Sun, Neville; Dwyer, Dan; Eisaman, Matthew D.; Haldar, Pradeep; Efstathiadis, Harry

    2015-09-05

    Cu(In1-x,Gax)Se2 (CIGS) absorber layers were deposited on molybdenum (Mo) coated soda-lime glass substrates with varying Ga content (described as Ga/(In+Ga) ratios) with respect to depth. As the responsible mechanisms for the limitation of the performance of the CIGS solar cells with high Ga contents are not well understood, the goal of this work was to investigate different properties of CIGS absorber films with Ga/(In+Ga) ratios varied between 0.29 and 0.41 (as determined by X-ray florescence spectroscopy (XRF)) in order to better understand the role that the Ga content has on film quality. The Ga grading in the CIGS layer hasmore » the effect causing a higher bandgap toward the surface and Mo contact while the band gap in the middle of the CIGS layer is lower. Also, a wider and larger Ga/(In+Ga) grading dip located deeper in the CIGS absorber layers tend to produce larger grains in the regions of the films that have lower Ga/(In+Ga) ratios. It was found that surface roughness decreases from 51.2 nm to 41.0 nm with increasing Ga/(In+Ga) ratios. However, the surface roughness generally decreases if the Ga grading occurs deeper in the absorber layer.« less

  9. 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.

  10. Dislocation related droop in InGaN/GaN light emitting diodes investigated via cathodoluminescence

    SciTech Connect (OSTI)

    Pozina, Galia; Ciechonski, Rafal; Bi, Zhaoxia; Samuelson, Lars; Monemar, Bo

    2015-12-21

    Today's energy saving solutions for general illumination rely on efficient white light emitting diodes (LEDs). However, the output efficiency droop experienced in InGaN based LEDs with increasing current injection is a serious limitation factor for future development of bright white LEDs. We show using cathodoluminescence (CL) spatial mapping at different electron beam currents that threading dislocations are active as nonradiative recombination centers only at high injection conditions. At low current, the dislocations are inactive in carrier recombination due to local potentials, but these potentials are screened by carriers at higher injection levels. In CL images, this corresponds to the increase of the dark contrast around dislocations with the injection (excitation) density and can be linked with droop related to the threading dislocations. Our data indicate that reduction of droop in the future efficient white LED can be achieved via a drastic reduction of the dislocation density by using, for example, bulk native substrates.

  11. Radiation resistance of GaAs-GaAlAs vertical cavity surface emitting lasers

    SciTech Connect (OSTI)

    Jabbour, J.; Zazoui, M.; Sun, G.C.; Bourgoin, J.C.; Gilard, O.

    2005-02-15

    The variations of the optical and electrical characteristics of a vertical cavity surface emitting laser based on GaAs quantum wells have been monitored versus irradiation with 1 MeV electrons. The results are understood by the introduction of nonradiative recombination centers in the wells whose characteristics, capture cross section for minority carriers times their introduction rate, can be determined. A similar study performed for proton irradiation shows that the results can be explained in the same way when the introduction rate of the defects is replaced by the proton energy loss into atomic collisions. These results allow us to deduce the equivalence between electron and proton irradiations: A flux of 1 proton cm{sup -2} which loses an energy E{sub nl} (eV) into atomic collisions is equivalent to a fluence of about 9x10{sup -2} E{sub nl} cm{sup -2}, 1 MeV electrons.

  12. 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.

  13. Vertical zone melt growth of GaAs

    SciTech Connect (OSTI)

    Henry, R.L.; Nordquist, P.E.R.; Gorman, R.J.

    1993-12-31

    A Vertical Zone Melt (VZM) technique has been applied to the single crystal growth of GaAs. A pyrolytic boron nitride crucible and a (100) oriented seed were used along with liquid encapsulation by boric oxide. In the case of GaAs, the ampoule was pressurized with either argon or argensic vapor from elemental arsenic at pressures ranging from 1 to 2 atmospheres. A molten zone length of 22 mm gave a growth interface which is nearly flat and resulted in routine single crystal growth. Temperature gradients of 4{degrees}C/cm. and 9{degrees}C/cm. have produced dislocation densities of <1000/cm{sup 2} and 2000-5000/cm{sup 2} respectively for 34 mm diameter crystals of GaAs. Post growth cooling rates for GaAs have been 35, 160 and 500{degrees}C/hr. The cooling rate has been found to affect the number and size of arsenic precipitates and the EL2 concentration in the GaAs crystal. The effects of these and other growth parameters on the crystalline perfection and electrical properties of the crystals will be discussed.

  14. Georgia Natural Gas Summary

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

    Imports 4.39 4.20 2.78 3.36 4.33 1999-2014 Pipeline and Distribution Use 1967-2005 Citygate 5.93 5.19 4.35 4.66 5.19 3.82 1984-2015 Residential 15.17 15.72 16.23 14.60 14.45 15.06 1967-2015 Commercial 10.95 10.51 9.75 9.38 9.86 8.49 1967-2015 Industrial 6.25 5.90 4.61 5.38 6.07 NA 1997-2015 Vehicle Fuel 5.17 5.57 14.51 1993-2012 Electric Power 5.21 4.72 3.40 4.45 4.98 3.27 1997-2015 Imports and Exports (Million Cubic Feet) Imports 106,454 75,641 59,266 15,575 7,155 1999-2014 Underground Storage

  15. Georgia Natural Gas Prices

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

    Pipeline and Distribution Use Price 1967-2005 Citygate Price 5.93 5.19 4.35 4.66 5.19 3.82 1984-2015 Residential Price 15.17 15.72 16.23 14.60 14.45 15.06 1967-2015 Percentage of ...

  16. ,"Georgia Natural Gas Prices"

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

    Date:","04292016" ,"Excel File Name:","ngprisumdcusgam.xls" ,"Available from Web Page:","http:www.eia.govdnavngngprisumdcusgam.htm" ,"Source:","Energy ...

  17. Georgia Natural Gas Summary

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

    35 3.27 3.21 3.19 3.37 3.44 1989-2016 Residential 10.79 10.94 13.01 16.48 20.53 24.74 1989-2016 Commercial 6.57 7.05 7.42 7.98 8.22 8.53 1989-2016 Industrial 4.02 3.95 3.46 3.45 3.50 3.54 2001-2016 Electric Power 3.05 W 2.23 2.40 2.44 3.03 2002-2016 Consumption (Million Cubic Feet) Delivered to Consumers 79,444 67,365 56,967 52,715 53,099 57,454 2001-2016 Residential 26,193 19,976 9,664 6,532 4,675 3,799 1989-2016 Commercial 10,325 7,942 4,397 3,215 2,448 2,064 1989-2016 Industrial 14,237 13,726

  18. Georgia Nuclear Profile - Vogtle

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

    ...vnd.ms-excel" 2,"1,152","9,363",92.8,"PWR","applicationvnd.ms-excel","applicationvnd.ms-excel" ,"2,302","19,610",97.2 "Data for 2010" "PWR Pressurized Light Water Reactor."

  19. Georgia Natural Gas Prices

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

    35 3.27 3.21 3.19 3.37 3.44 1989-2016 Residential Price 10.79 10.94 13.01 16.48 20.53 24.74 1989-2016 Percentage of Total Residential Deliveries included in Prices 100.0 100.0 100.0 100.0 100.0 100.0 2002-2016 Commercial Price 6.57 7.05 7.42 7.98 8.22 8.53 1989-2016 Percentage of Total Commercial Deliveries included in Prices 100.0 100.0 100.0 100.0 100.0 100.0 1989-2016 Industrial Price 4.02 3.95 3.46 3.45 3.50 3.54 2001-2016 Percentage of Total Industrial Deliveries included in Prices 20.0

  20. Georgia Nuclear Profile - Vogtle

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

    Vogtle" "Unit","Summer capacity (mw)","Net generation (thousand mwh)","Summer capacity factor (percent)","Type","Commercial operation date","License expiration date" 1,"1,150","10,247",101.7,"PWR","application/vnd.ms-excel","application/vnd.ms-excel"

  1. 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

  2. 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.

  3. 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.

  4. RECONNAISSANCE ASSESSMENT OF CO2 SEQUESTRATION POTENTIAL IN THE TRIASSIC AGE RIFT BASIN TREND OF SOUTH CAROLINA, GEORGIA, AND NORTHERN FLORIDA

    SciTech Connect (OSTI)

    Blount, G.; Millings, M.

    2011-08-01

    A reconnaissance assessment of the carbon dioxide (CO{sub 2}) sequestration potential within the Triassic age rift trend sediments of South Carolina, Georgia and the northern Florida Rift trend was performed for the Office of Fossil Energy, National Energy Technology Laboratory (NETL). This rift trend also extends into eastern Alabama, and has been termed the South Georgia Rift by previous authors, but is termed the South Carolina, Georgia, northern Florida, and eastern Alabama Rift (SGFAR) trend in this report to better describe the extent of the trend. The objectives of the study were to: (1) integrate all pertinent geologic information (literature reviews, drilling logs, seismic data, etc.) to create an understanding of the structural aspects of the basin trend (basin trend location and configuration, and the thickness of the sedimentary rock fill), (2) estimate the rough CO{sub 2} storage capacity (using conservative inputs), and (3) assess the general viability of the basins as sites of large-scale CO{sub 2} sequestration (determine if additional studies are appropriate). The CO{sub 2} estimates for the trend include South Carolina, Georgia, and northern Florida only. The study determined that the basins within the SGFAR trend have sufficient sedimentary fill to have a large potential storage capacity for CO{sub 2}. The deeper basins appear to have sedimentary fill of over 15,000 feet. Much of this fill is likely to be alluvial and fluvial sedimentary rock with higher porosity and permeability. This report estimates an order of magnitude potential capacity of approximately 137 billion metric tons for supercritical CO{sub 2}. The pore space within the basins represent hundreds of years of potential storage for supercritical CO{sub 2} and CO{sub 2} stored in aqueous form. There are many sources of CO{sub 2} within the region that could use the trend for geologic storage. Thirty one coal fired power plants are located within 100 miles of the deepest portions of

  5. Highly transparent ammonothermal bulk GaN substrates

    SciTech Connect (OSTI)

    Jiang, WK; Ehrentraut, D; Downey, BC; Kamber, DS; Pakalapati, RT; Do Yoo, H; D'Evelyn, MP

    2014-10-01

    A novel apparatus has been employed to grow ammonothermal (0001) gallium nitride (GaN) with diameters up to 2 in The crystals have been characterized by x-ray diffraction rocking-curve (XRC) analysis, optical and scanning electron microscopy (SEM), cathodoluminescence (CL), and optical spectroscopy. High crystallinity GaN with FWHM values about 20-50 arcsec and dislocation densities below 1 x 10(5) cm(-2) have been obtained. High optical transmission was achieved with an optical absorption coefficient below 1 cm(-1) at a wavelength of 450 nm. (C) 2014 Elsevier B.V. All rights reserved.

  6. Graphene/GaN diodes for ultraviolet and visible photodetectors

    SciTech Connect (OSTI)

    Lin, Fang; Chen, Shao-Wen; Meng, Jie; Tse, Geoffrey; Fu, Xue-Wen; Xu, Fu-Jun [State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871 (China); Shen, Bo; Liao, Zhi-Min, E-mail: liaozm@pku.edu.cn, E-mail: yudp@pku.edu.cn; Yu, Da-Peng, E-mail: liaozm@pku.edu.cn, E-mail: yudp@pku.edu.cn [State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter, Beijing (China)

    2014-08-18

    The Schottky diodes based on graphene/GaN interface are fabricated and demonstrated for the dual-wavelength photodetection of ultraviolet (UV) and green lights. The physical mechanisms of the photoelectric response of the diodes with different light wavelengths are different. For UV illumination, the photo-generated carriers lower the Schottky barrier and increase the photocurrent. For green light illumination, as the photon energy is smaller than the bandgap of GaN, the hot electrons excited in graphene via internal photoemission are responsible for the photoelectric response. Using graphene as a transparent electrode, the diodes show a ?mS photoresponse, providing an alternative route toward multi-wavelength photodetectors.

  7. Simple intrinsic defects in GaAs : numerical supplement.

    SciTech Connect (OSTI)

    Schultz, Peter Andrew

    2012-04-01

    This Report presents numerical tables summarizing properties of intrinsic defects in gallium arsenide, GaAs, as computed by density functional theory. This Report serves as a numerical supplement to the results published in: P.A. Schultz and O.A. von Lilienfeld, 'Simple intrinsic defects in GaAs', Modelling Simul. Mater. Sci Eng., Vol. 17, 084007 (2009), and intended for use as reference tables for a defect physics package in device models. The numerical results for density functional theory calculations of properties of simple intrinsic defects in gallium arsenide are presented.

  8. Electronic contribution to friction on GaAs

    SciTech Connect (OSTI)

    Applied Science and Technology Graduate Group, UC Berkeley; Dept. of Materials Sciences and Engineering, UC Berkeley; Salmeron, Miquel; Qi, Yabing; Park, J.Y.; Hendriksen, B.L.M.; Ogletree, D.F.; Salmeron, Miquel

    2008-04-15

    The electronic contribution to friction at semiconductor surfaces was investigated by using a Pt-coated tip with 50nm radius in an atomic force microscope sliding against an n-type GaAs(100) substrate. The GaAs surface was covered by an approximately 1 nm thick oxide layer. Charge accumulation or depletion was induced by the application of forward or reverse bias voltages. We observed a substantial increase in friction force in accumulation (forward bias) with respect to depletion (reverse bias). We propose a model based on the force exerted by the trapped charges that quantitatively explains the experimental observations of excess friction.

  9. Polycrystalline MBE-grown GaAs for solar cells

    SciTech Connect (OSTI)

    Friedman, D.J.; Kurtz, S.R.; Kibbler, A.E.; Al-Jassim, M.; Jones, K.; Keyes, B.; Matson, R.

    1997-02-01

    This paper will discuss initial studies of thin-film GaAs grown by molecular-beam epitaxy for use in developing a thin-film GaAs solar cell. Photocurrent and photoluminescence intensity are related to the material morphology as a function of growth conditions. Growth temperature and V/III ratio have a dramatic effect on the photocurrent. However, it seems likely that even after optimizing such growth parameters, it will be necessary to provide substrates that can provide templates to enhance grain size from the start of thin-film growth. {copyright} {ital 1997 American Institute of Physics.}

  10. Polycrystalline MBE-grown GaAs for solar cells

    SciTech Connect (OSTI)

    Friedman, D. J.; Kurtz, Sarah R.; Kibbler, A. E.; Al-Jassim, M.; Jones, K.; Keyes, B.; Matson, R.

    1997-02-15

    This paper will discuss initial studies of thin-film GaAs grown by molecular-beam epitaxy for use in developing a thin-film GaAs solar cell. Photocurrent and photoluminescence intensity are related to the material morphology as a function of growth conditions. Growth temperature and V/III ratio have a dramatic effect on the photocurrent. However, it seems likely that even after optimizing such growth parameters, it will be necessary to provide substrates that can provide templates to enhance grain size from the start of thin-film growth.

  11. 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.

  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. Alloy inhomogeneity and carrier localization in AlGaN sections and AlGaN/AlN nanodisks in nanowires with 240350?nm emission

    SciTech Connect (OSTI)

    Himwas, C.; Hertog, M. den; Dang, Le Si; Songmuang, R.; Monroy, E.

    2014-12-15

    We present structural and optical studies of AlGaN sections and AlGaN/AlN nanodisks (NDs) in nanowires grown by plasma-assisted molecular beam epitaxy. The Al-Ga intermixing at Al(Ga)N/GaN interfaces and the chemical inhomogeneity in AlGaN NDs evidenced by scanning transmission electron microscopy are attributed to the strain relaxation process. This interpretation is supported by the three-dimensional strain distribution calculated by minimizing the elastic energy in the structure. The alloy inhomogeneity increases with the Al content, leading to enhanced carrier localization signatures in the luminescence characteristics, i.e., red shift of the emission, s-shaped temperature dependence, and linewidth broadening. Despite these effects, the emission energy of AlGaN/AlN NDs can be tuned in the 240350?nm range with internal quantum efficiencies around 30%.

  14. Characteristics of InGaP/InGaAs pseudomorphic high electron mobility transistors with triple delta-doped sheets

    SciTech Connect (OSTI)

    Chu, Kuei-Yi; Chiang, Meng-Hsueh Cheng, Shiou-Ying; Liu, Wen-Chau

    2012-02-15

    Fundamental and insightful characteristics of InGaP/InGaAs double channel pseudomorphic high electron mobility transistors (DCPHEMTs) with graded and uniform triple {delta}-doped sheets are coomprehensively studied and demonstrated. To gain physical insight, band diagrams, carrier densities, and direct current characteristics of devices are compared and investigated based on the 2D semiconductor simulator, Atlas. Due to uniform carrier distribution and high electron density in the double InGaAs channel, the DCPHEMT with graded triple {delta}-doped sheets exhibits better transport properties, higher and linear transconductance, and better drain current capability as compared with the uniformly triple {delta}-doped counterpart. The DCPHEMT with graded triple {delta}-doped structure is fabricated and tested, and the experimental data are found to be in good agreement with simulated results.

  15. High-performance broadband optical coatings on InGaN/GaN solar cells for multijunction device integration

    SciTech Connect (OSTI)

    Young, N. G. Farrell, R. M.; Iza, M.; Speck, J. S.; Perl, E. E.; Keller, S.; Bowers, J. E.; Nakamura, S.; DenBaars, S. P.

    2014-04-21

    We demonstrate InGaN/GaN multiple quantum well solar cells grown by metalorganic chemical vapor deposition on a bulk (0001) substrate with high-performance broadband optical coatings to improve light absorption. A front-side anti-reflective coating and a back-side dichroic mirror were designed to minimize front surface reflections across a broad spectral range and maximize rear surface reflections only in the spectral range absorbed by the InGaN, making the cells suitable for multijunction solar cell integration. Application of optical coatings increased the peak external quantum efficiency by 56% (relative) and conversion efficiency by 37.5% (relative) under 1 sun AM0 equivalent illumination.

  16. Fabrication and Characterization of a Single Hole Transistor in p-type GaAs/AlGaAs Heterostructures

    SciTech Connect (OSTI)

    Tracy, Lisa A; Reno, John L.; Hargett, Terry W.

    2015-09-01

    Most spin qubit research to date has focused on manipulating single electron spins in quantum dots. However, hole spins are predicted to have some advantages over electron spins, such as reduced coupling to host semiconductor nuclear spins and the ability to control hole spins electrically using the large spin-orbit interaction. Building on recent advances in fabricating high-mobility 2D hole systems in GaAs/AlGaAs heterostructures at Sandia, we fabricate and characterize single hole transistors in GaAs. We demonstrate p-type double quantum dot devices with few-hole occupation, which could be used to study the physics of individual hole spins and control over coupling between hole spins, looking towards eventual applications in quantum computing. Intentionally left blank

  17. Terahertz intersubband absorption in non-polar m-plane AlGaN/GaN quantum wells

    SciTech Connect (OSTI)

    Edmunds, C.; Malis, O.; Shao, J.; Shirazi-HD, M.; Manfra, M. J.

    2014-07-14

    We demonstrate THz intersubband absorption (15.6–26.1 meV) in m-plane AlGaN/GaN quantum wells. We find a trend of decreasing peak energy with increasing quantum well width, in agreement with theoretical expectations. However, a blue-shift of the transition energy of up to 14 meV was observed relative to the calculated values. This blue-shift is shown to decrease with decreasing charge density and is, therefore, attributed to many-body effects. Furthermore, a ∼40% reduction in the linewidth (from roughly 8 to 5 meV) was obtained by reducing the total sheet density and inserting undoped AlGaN layers that separate the wavefunctions from the ionized impurities in the barriers.

  18. Inversion-mode GaAs wave-shaped field-effect transistor on GaAs (100) substrate

    SciTech Connect (OSTI)

    Zhang, Jingyun; Si, Mengwei; Wu, Heng; Ye, Peide D.; Lou, Xiabing; Gordon, Roy G.; Shao, Jiayi; Manfra, Michael J.

    2015-02-16

    Inversion-mode GaAs wave-shaped metal-oxide-semiconductor field-effect transistors (WaveFETs) are demonstrated using atomic-layer epitaxy of La{sub 2}O{sub 3} as gate dielectric on (111)A nano-facets formed on a GaAs (100) substrate. The wave-shaped nano-facets, which are desirable for the device on-state and off-state performance, are realized by lithographic patterning and anisotropic wet etching with optimized geometry. A well-behaved 1 μm gate length GaAs WaveFET shows a maximum drain current of 64 mA/mm, a subthreshold swing of 135 mV/dec, and an I{sub ON}/I{sub OFF} ratio of greater than 10{sup 7}.

  19. Degradation of InGaN/GaN laser diodes investigated by micro-cathodoluminescence and micro-photoluminescence

    SciTech Connect (OSTI)

    Meneghini, M. Carraro, S.; Meneghesso, G.; Trivellin, N.; Zanoni, E.; Rossi, F.; Salviati, G.; Schade, L.; Karunakaran, M. A.; Schwarz, U. T.

    2013-12-02

    We present an investigation of the degradation of InGaN/GaN laser diodes grown on a GaN substrate. The results indicate that: (i) Ageing induces a significant increase in the threshold current (Ith) of the lasers, which is attributed to an increase in non-radiative recombination; (ii) Ith increase is correlated to a decrease in the micro-cathodoluminescence signal measured (after the removal of the top metallization) in the region under the ridge; (iii) micro-photoluminescence measurements indicate that constant current stress increases non-radiative recombination within the quantum wells (and not only within the barriers), and induces an increase in the emission wavelength of the degraded region.

  20. Strong enhancement of terahertz emission from GaAs in InAs/GaAs quantum dot structures

    SciTech Connect (OSTI)

    Estacio, Elmer; Pham, Minh Hong; Takatori, Satoru; Cadatal-Raduban, Marilou; Nakazato, Tomoharu; Shimizu, Toshihiko; Sarukura, Nobuhiko; Somintac, Armando; Defensor, Michael; Awitan, Fritz Christian B.; Jaculbia, Rafael B.; Salvador, Arnel; Garcia, Alipio

    2009-06-08

    We report on the intense terahertz emission from InAs/GaAs quantum dot (QD) structures grown by molecular beam epitaxy. Results reveal that the QD sample emission was as high as 70% of that of a p-type InAs wafer, the most intense semiconductor emitter to date. Excitation wavelength studies showed that the emission was due to absorption in strained undoped GaAs, and corresponds to a two order-of-magnitude enhancement. Moreover, it was found that multilayer QDs emit more strongly compared with a single layer QD sample. At present, we ascribe the intense radiation to huge strain fields at the InAs/GaAs interface.

  1. Current transient spectroscopy for trapping analysis on Au-free AlGaN/GaN Schottky barrier diode

    SciTech Connect (OSTI)

    Hu, J. Groeseneken, G.; Stoffels, S.; Lenci, S.; Venegas, R.; Decoutere, S.; Bakeroot, B.

    2015-02-23

    This paper presents a combined technique of high voltage off-state stress and current transient measurements to investigate the trapping/de-trapping characteristics of Au-free AlGaN/GaN Schottky barrier diodes. The device features a symmetric three-terminal structure with a central anode contact surrounded by two separate cathodes. Under the diode off-state stress conditions, the two separate cathodes were electrically shorted. The de-trapping dynamics was studied by monitoring the recovery of the two-dimensional electron gas (2DEG) current at different temperatures by applying 0.5?V at cathode 2 while grounding cathode 1. During the recovery, the anode contact acts as a sensor of changes in diode leakage current. This leakage variation was found to be mainly due to the barrier height variation. With this method, the energy level and capture cross section of different traps in the AlGaN/GaN Schottky barrier diode can be extracted. Furthermore, the physical location of different trapping phenomena is indicated by studying the variation of the diode leakage current during the recovery. We have identified two distinct trapping mechanisms: (i) electron trapping at the AlGaN surface in the vicinity of the Schottky contact which results in the leakage reduction (barrier height ?{sub B} increase) together with R{sub ON} degradation; (ii) the electron trapping in the GaN channel layer which partially depletes the 2DEG. The physical origin of the two different traps is discussed in the text.

  2. Emission spectra of a laser based on an In(Ga)As/GaAs quantum-dot superlattice

    SciTech Connect (OSTI)

    Sobolev, M. M. Buyalo, M. S.; Nevedomskiy, V. N.; Zadiranov, Yu. M.; Zolotareva, R. V.; Vasil’ev, A. P.; Ustinov, V. M.; Portnoi, E. L.

    2015-10-15

    The spectral characteristics of a laser with an active region based on a ten-layer system of In(Ga)As/GaAs vertically correlated quantum dots with 4.5-nm GaAs spacer layers between InAs quantum dots are studied under the conditions of spontaneous and stimulated emission, depending on the current and the duration of pump pulses. Data obtained by transmission electron microscopy and electroluminescence and absorption polarization anisotropy measurements make it possible to demonstrate that the investigated system of tunnel-coupled InAs quantum dots separated by thin GaAs barriers represents a quantum-dot superlattice. With an increase in the laser pump current, the electroluminescence intensity increases linearly and the spectral position of the electroluminescence maximum shifts to higher energies, which is caused by the dependence of the miniband density-of-states distribution on the pump current. Upon exceeding the threshold current, multimode lasing via the miniband ground state is observed. One of the lasing modes can be attributed to the zero-phonon line, and the other is determined by the longitudinal-optical phonon replica of quantum-dot emission. The results obtained give evidence that, under conditions of the laser pumping of an In(Ga)As/GaAs quantum-dot superlattice, strong coupling between the discrete electron states in the miniband and optical phonons takes place. This leads to the formation of quantum-dot polarons, resulting from the resonant mixing of electronic states whose energy separation is comparable to the optical-phonon energy.

  3. InGaAs/GaAsP strain balanced multi-quantum wires grown on misoriented GaAs substrates for high efficiency solar cells

    SciTech Connect (OSTI)

    Alonso-lvarez, D.; Thomas, T.; Fhrer, M.; Hylton, N. P.; Ekins-Daukes, N. J.; Lackner, D.; Philipps, S. P.; Bett, A. W.; Sodabanlu, H.; Fujii, H.; Watanabe, K.; Sugiyama, M.; Nasi, L.; Campanini, M.

    2014-08-25

    Quantum wires (QWRs) form naturally when growing strain balanced InGaAs/GaAsP multi-quantum wells (MQW) on GaAs [100] 6 misoriented substrates under the usual growth conditions. The presence of wires instead of wells could have several unexpected consequences for the performance of the MQW solar cells, both positive and negative, that need to be assessed to achieve high conversion efficiencies. In this letter, we study QWR properties from the point of view of their performance as solar cells by means of transmission electron microscopy, time resolved photoluminescence and external quantum efficiency (EQE) using polarised light. We find that these QWRs have longer lifetimes than nominally identical QWs grown on exact [100] GaAs substrates, of up to 1??s, at any level of illumination. We attribute this effect to an asymmetric carrier escape from the nanostructures leading to a strong 1D-photo-charging, keeping electrons confined along the wire and holes in the barriers. In principle, these extended lifetimes could be exploited to enhance carrier collection and reduce dark current losses. Light absorption by these QWRs is 1.6 times weaker than QWs, as revealed by EQE measurements, which emphasises the need for more layers of nanostructures or the use light trapping techniques. Contrary to what we expected, QWR show very low absorption anisotropy, only 3.5%, which was the main drawback a priori of this nanostructure. We attribute this to a reduced lateral confinement inside the wires. These results encourage further study and optimization of QWRs for high efficiency solar cells.

  4. Defect-Reduction Mechanism for Improving Radiative Efficiency in InGaN/GaN Light-Emitting Diodes using InGaN Underlayers

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

    Armstrong, Andrew M.; Bryant, Benjamin N.; Crawford, Mary H.; Koleske, Daniel D.; Lee, Stephen R.; Wierer, Jr., Jonathan J.

    2015-04-01

    The influence of a dilute InxGa1-xN (x~0.03) underlayer (UL) grown below a single In0.16Ga0.84N quantum well (SQW), within a light-emitting diode(LED), on the radiative efficiency and deep level defect properties was studied using differential carrier lifetime (DCL) measurements and deep level optical spectroscopy (DLOS). DCL measurements found that inclusion of the UL significantly improved LED radiative efficiency. At low current densities, the non-radiative recombination rate of the LED with an UL was found to be 3.9 times lower than theLED without an UL, while the radiative recombination rates were nearly identical. This, then, suggests that the improved radiative efficiency resultedmore » from reduced non-radiative defect concentration within the SQW. DLOS measurement found the same type of defects in the InGaN SQWs with and without ULs. However, lighted capacitance-voltage measurements of the LEDs revealed a 3.4 times reduction in a SQW-related near-mid-gap defect state for the LED with an UL. Furthermore, quantitative agreement in the reduction of both the non-radiative recombination rate (3.9×) and deep level density (3.4×) upon insertion of an UL corroborates deep level defect reduction as the mechanism for improved LED efficiency.« less

  5. Excitonic transitions in highly efficient (GaIn)As/Ga(AsSb) type-II quantum-well structures

    SciTech Connect (OSTI)

    Gies, S.; Kruska, C.; Berger, C.; Hens, P.; Fuchs, C.; Rosemann, N. W.; Veletas, J.; Stolz, W.; Koch, S. W.; Heimbrodt, W.; Ruiz Perez, A.; Hader, J.; Moloney, J. V.

    2015-11-02

    The excitonic transitions of the type-II (GaIn)As/Ga(AsSb) gain medium of a “W”-laser structure are characterized experimentally by modulation spectroscopy and analyzed using microscopic quantum theory. On the basis of the very good agreement between the measured and calculated photoreflectivity, the type-I or type-II character of the observable excitonic transitions is identified. Whereas the energetically lowest three transitions exhibit type-II character, the subsequent energetically higher transitions possess type-I character with much stronger dipole moments. Despite the type-II character, the quantum-well structure exhibits a bright luminescence.

  6. Properties of H, O and C in GaN

    SciTech Connect (OSTI)

    Pearton, S.J.; Abernathy, C.R.; Lee, J.W.

    1996-04-01

    The electrical properties of the light ion impurities H, O and C in GaN have been examined in both as-grown and implanted material. H is found to efficiently passivate acceptors such as Mg, Ca and C. Reactivation occurs at {ge} 450 C and is enhanced by minority carrier injection. The hydrogen does not leave the GaN crystal until > 800 C, and its diffusivity is relatively high ({approximately} 10{sup {minus}11} cm{sup 2}/s) even at low temperatures (< 200 C) during injection by wet etching, boiling in water or plasma exposure. Oxygen shows a low donor activation efficiency when implanted into GaN, with an ionization level of 30--40 meV. It is essentially immobile up to 1,100 C. Carbon can produce low p-type levels (3 {times} 10{sup 17} cm{sup {minus}3}) in GaN during MOMBE, although there is some evidence it may also create n-type conduction in other nitrides.

  7. Testing a GaAs cathode in SRF gun

    SciTech Connect (OSTI)

    Wang, E.; Kewisch, J.; Ben-Zvi, I.; Burrill, A.; Rao, T.; Wu, Q.; Holmes, D.

    2011-03-28

    RF electron guns with a strained superlattice GaAs cathode are expected to generate polarized electron beams of higher brightness and lower emittance than do DC guns, due to their higher field gradient at the cathode's surface and lower cathode temperature. We plan to install a bulk GaAs:Cs in a SRF gun to evaluate the performance of both the gun and the cathode in this environment. The status of this project is: In our 1.3 GHz 1/2 cell SRF gun, the vacuum can be maintained at nearly 10{sup -12} Torr because of cryo-pumping at 2K. With conventional activation of bulk GaAs, we obtained a QE of 10% at 532 nm, with lifetime of more than 3 days in the preparation chamber and have shown that it can survive in transport from the preparation chamber to the gun. The beam line has been assembled and we are exploring the best conditions for baking the cathode under vacuum. We report here the progress of our test of the GaAs cathode in the SRF gun. Future particle accelerators, such as eRHIC and the ILC require high-brightness, high-current polarized electrons. Strained superlattice GaAs:Cs has been shown to be an efficient cathode for producing polarized electrons. Activation of GaAs with Cs,O(F) lowers the electron affinity and makes it energetically possible for all the electrons, excited into the conduction band that drift or diffuse to the emission surface, to escape into the vacuum. Presently, all operating polarized electron sources, such as the CEBAF, are DC guns. In these devices, the excellent ultra-high vacuum extends the lifetime of the cathode. However, the low field gradient on the photocathode's emission surface of the DC guns limits the beam quality. The higher accelerating gradients, possible in the RF guns, generate a far better beam. Until recently, most RF guns operated at room temperature, limiting the vacuum to {approx}10{sup -9} Torr. This destroys the GaAs's NEA surface. The SRF guns combine the excellent vacuum conditions of DC guns and the high

  8. Quaternary InGaAsSb Thermophotovoltaic Diodes

    SciTech Connect (OSTI)

    MW Dashiell; JF Beausang; H Ehsani; GJ Nichols; DM Depoy; LR Danielson; P Talamo; KD Rahner; EJ Brown; SR Burger; PM Foruspring; WF Topper; PF Baldasaro; CA Wang; R Huang; M Connors; G Turner; Z Shellenbarger; G Taylor; J Li; R Martinelli; D Donetski; S Anikeev; G Belenky; S Luryi

    2006-03-09

    In{sub x}Ga{sub 1-x}As{sub y}Sb{sub 1-y} thermophotovoltaic (TPV) diodes were grown lattice-matched to GaSb substrates by Metal Organic Vapor Phase Epitaxy (MOVPE) in the bandgap range of E{sub G} = 0.5 to 0.6eV. InGaAsSb TPV diodes, utilizing front-surface spectral control filters, are measured with thermal-to-electric conversion efficiency and power density of {eta}{sub TPV} = 19.7% and PD =0.58 W/cm{sup 2} respectively for a radiator temperature of T{sub radiator} = 950 C, diode temperature of T{sub diode} = 27 C, and diode bandgap of E{sub G} = 0.53eV. Practical limits to TPV energy conversion efficiency are established using measured recombination coefficients and optical properties of front surface spectral control filters, which for 0.53eV InGaAsSb TPV energy conversion is {eta}{sub TPV} = 28% and PD = 0.85W/cm{sup 2} at the above operating temperatures. The most severe performance limits are imposed by (1) diode open-circuit voltage (VOC) limits due to intrinsic Auger recombination and (2) parasitic photon absorption in the inactive regions of the module. Experimentally, the diode V{sub OC} is 15% below the practical limit imposed by intrinsic Auger recombination processes. Analysis of InGaAsSb diode electrical performance vs. diode architecture indicate that the V{sub OC} and thus efficiency is limited by extrinsic recombination processes such as through bulk defects.

  9. Ge doped GaN with controllable high carrier concentration for...

    Office of Scientific and Technical Information (OSTI)

    Ge doped GaN with controllable high carrier concentration for plasmonic applications Citation Details In-Document Search Title: Ge doped GaN with controllable high carrier...

  10. Correlation of DLTS and Performance of GaInNAs Cells

    SciTech Connect (OSTI)

    Kurtz, S.; Johnston, S.; Friedman, D.; Ptak, A.; Geisz, J.; McMahon, W.; Olson, J.; Kibbler, A.; Crandall, R.; Ahrenkiel, R.; Kramer, C.; Young, M.

    2005-01-01

    A four-junction GaInP/GaAs/GaInAsN/Ge solar cell should be able to reach 40% efficiency if each of the junctions can be made with a quality similar to that demonstrated for GaAs. However, the GaInAsN subcell has shown poor performance. Deep-level transient spectroscopy (DLTS) can elucidate recombination centers in a material and could help identify the problem with the GaInAsN. So far, DLTS studies of GaInAsN have shown many peaks. In this paper we compare the performance of the GaInAsN solar cells with the DLTS spectra to identify which DLTS peak is correlated with the device performance.

  11. Bismuth-induced phase control of GaAs nanowires grown by molecular...

    Office of Scientific and Technical Information (OSTI)

    Bismuth-induced phase control of GaAs nanowires grown by molecular beam epitaxy Citation Details In-Document Search Title: Bismuth-induced phase control of GaAs nanowires grown by ...

  12. Site-controlled fabrication of Ga nanodroplets by focused ion beam

    SciTech Connect (OSTI)

    Xu, Xingliang; Wang, Zhiming M.; Wu, Jiang; Li, Handong; Zhou, Zhihua; Wang, Xiaodong

    2014-03-31

    Ga droplets are created by focused ion beam irradiation of GaAs surface. We report that ordered Ga droplets can be formed on the GaAs surface without any implantation damage. The droplets are characterized with bigger sizes than those droplets formed on damaged area. These aligned Ga droplets are formed via the migration of Ga atoms from ion irradiation area to the edge of undamaged GaAs surface and further nucleation into droplets. The morphological evolution and size distribution of these nanodroplets are investigated systematically with different beam irradiation time and incident angles. Based on this method, well positioned Ga nanodroplets, such as chains, are achieved by using focus ion beam patterning. The controllable assembly of droplets on undamaged semiconductor surface can be used to fabricate templates, to fabricate quantum structures and quantum devices by droplet epitaxy technique.

  13. Surface Chemistry of GaP(001) and InP(001) in Contact with Water...

    Office of Scientific and Technical Information (OSTI)

    Surface Chemistry of GaP(001) and InP(001) in Contact with Water Citation Details In-Document Search Title: Surface Chemistry of GaP(001) and InP(001) in Contact with Water ...

  14. Reactive codoping of GaAlInP compound semiconductors (Patent...

    Office of Scientific and Technical Information (OSTI)

    This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and ... A GaAlInP compound semiconductor and a method of producing a GaAlInP compound ...

  15. 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 ...

  16. Contrasting Behavior of GaP(001) and InP(001) at the Interface...

    Office of Scientific and Technical Information (OSTI)

    Contrasting Behavior of GaP(001) and InP(001) at the Interface with Water Citation Details In-Document Search Title: Contrasting Behavior of GaP(001) and InP(001) at the Interface ...

  17. Structure and magnetic properties of Ce₃(Ni/Al/Ga)₁₁-A...

    Office of Scientific and Technical Information (OSTI)

    ...AlGa)-A new phase with the LaAl structure type Prev Next Title: Structure and magnetic properties of Ce(NiAlGa)-A new phase with the ...

  18. Dislocation confinement in the growth of Na flux GaN on metalorganic...

    Office of Scientific and Technical Information (OSTI)

    Dislocation confinement in the growth of Na flux GaN on metalorganic chemical vapor deposition-GaN Citation Details In-Document Search Title: Dislocation confinement in the growth ...

  19. Electron-limiting defect complex in hyperdoped GaAs: The D D...

    Office of Scientific and Technical Information (OSTI)

    Electron-limiting defect complex in hyperdoped GaAs: The D D X center Prev Next Title: Electron-limiting defect complex in hyperdoped GaAs: The D D X center Authors: Ma, Jie ...

  20. Coexistence of charge-density wave and ferromagnetism in Ni2MnGa...

    Office of Scientific and Technical Information (OSTI)

    Coexistence of charge-density wave and ferromagnetism in Ni2MnGa Citation Details In-Document Search Title: Coexistence of charge-density wave and ferromagnetism in Ni2MnGa ...

  1. Southface Energy Institute: Advanced Commercial Buildings Initiative

    Broader source: Energy.gov [DOE]

    Lead Performer: Southface Energy Institute – Atlanta, GA Partners: - City of Atlanta – Atlanta, GA - Georgia Institute of Technology – Atlanta, GA - Kendeda Fund – Atlanta, GA - Oak Ridge National Laboratory – Oak Ridge, TN - Acuity Brands Lighting – Atlanta, GA - Vermont Energy Investment Corp – Burlington, VT - Georgia Power– Atlanta, GA - Southeast Energy Efficiency Alliance – Atlanta, GA - JPB Foundation – New York, NY - Central Atlanta Progress – Atlanta, GA

  2. Influence of Ga content on the structure and anomalous Hall effect of Fe{sub 1−x}Ga{sub x} thin films on GaSb(100)

    SciTech Connect (OSTI)

    Anh Tuan, Duong; Shin, Yooleemi; Viet Cuong, Tran; Cho, Sunglae; Phan, The-Long

    2014-05-07

    The Fe{sub 1−x}Ga{sub x} thin films (x = 0.4, 0.5) have been grown on GaSb(100) substrate using molecular beam epitaxy. An epitaxial film with bcc α-Fe crystal structure (A2) is observed in Fe{sub 0.6}Ga{sub 0.4} film, while an impure Fe{sub 3}Ga phase with DO{sub 3} structure is appeared in Fe{sub 0.5}Ga{sub 0.5} film. The saturated magnetizations at room temperature are observed to be 570 emu/cm{sup 3} and 180 emu/cm{sup 3} and the coercivities to be 170 and 364 Oe for Fe{sub 0.6}Ga{sub 0.4} and Fe{sub 0.5}Ga{sub 0.5}, respectively. A hysteresis trend in Hall resistance vs. magnetic field is observed for Fe{sub 0.5}Ga{sub 0.5} film. However, there is a weak hysteresis noticed in Fe{sub 0.4}Ga{sub 0.6} thin film.

  3. Plasmonic terahertz detectors based on a high-electron mobility GaAs/AlGaAs heterostructure

    SciTech Connect (OSTI)

    Bia?ek, M. Witowski, A. M.; Grynberg, M.; ?usakowski, J.; Orlita, M.; Potemski, M.; Czapkiewicz, M.; Umansky, V.

    2014-06-07

    In order to characterize magnetic field (B) tunable THz plasmonic detectors, spectroscopy experiments were carried out at liquid helium temperatures and high magnetic fields on devices fabricated on a high electron mobility GaAs/AlGaAs heterostructure. The samples were either gated (the gate of a meander shape) or ungated. Spectra of a photovoltage generated by THz radiation were obtained as a function of B at a fixed THz excitation from a THz laser or as a function of THz photon frequency at a fixed B with a Fourier spectrometer. In the first type of measurements, the wave vector of magnetoplasmons excited was defined by geometrical features of samples. It was also found that the magnetoplasmon spectrum depended on the gate geometry which gives an additional parameter to control plasma excitations in THz detectors. Fourier spectra showed a strong dependence of the magnetoplasmon resonance amplitude on the conduction-band electron filling factor which was explained within a model of the electron gas heating with THz radiation. The study allows to define both the advantages and limitations of plasmonic devices based on high-mobility GaAs/AlGaAs heterostructures for THz detection at low temperatures and high magnetic fields.

  4. On the redox origin of surface trapping in AlGaN/GaN high electron mobility transistors

    SciTech Connect (OSTI)

    Gao, Feng; Chen, Di; Tuller, Harry L.; Thompson, Carl V.; Palacios, Toms

    2014-03-28

    Water-related redox couples in ambient air are identified as an important source of the surface trapping states, dynamic on-resistance, and drain current collapse in AlGaN/GaN high electron mobility transistors (HEMTs). Through in-situ X-ray photoelectron spectroscopy (XPS), direct signature of the water-related specieshydroxyl groups (OH) was found at the AlGaN surface at room temperature. It was also found that these species, as well as the current collapse, can be thermally removed above 200?C in vacuum conditions. An electron trapping mechanism based on the H{sub 2}O/H{sub 2} and H{sub 2}O/O{sub 2} redox couples is proposed to explain the 0.5?eV energy level commonly attributed to the surface trapping states. Finally, the role of silicon nitride passivation in successfully removing current collapse in these devices is explained by blocking the water molecules away from the AlGaN surface.

  5. High 400?C operation temperature blue spectrum concentration solar junction in GaInN/GaN

    SciTech Connect (OSTI)

    Zhao, Liang; Detchprohm, Theeradetch; Wetzel, Christian

    2014-12-15

    Transparent wide gap junctions suitable as high temperature, high flux topping cells have been achieved in GaInN/GaN by metal-organic vapor phase epitaxy. In structures of 25 quantum wells (QWs) under AM1.5G illumination, an open circuit voltage of 2.1?V is achieved. Of the photons absorbed in the limited spectral range of <450?nm, 64.2% are converted to electrons collected at the contacts under zero bias. At a fill factor of 45%, they account for a power conversion efficiency of38.6%. Under concentration, the maximum output power density per sun increases from 0.49?mW/cm{sup 2} to 0.51?mW/cm{sup 2} at 40?suns and then falls 0.42?mW/cm{sup 2} at 150?suns. Under external heating, a maximum of 0.59?mW/cm{sup 2} is reached at 250?C. Even at 400?C, the device is fully operational and exceeds room temperature performance. A defect analysis suggests that significantly higher fill factors and extension into longer wavelength ranges are possible with further development. The results prove GaInN/GaN QW solar junctions a viable and rugged topping cell for concentrator photovoltaics with minimal cooling requirements. By capturing the short range spectrum, they reduce the thermal load to any conventional cells stacked behind.

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

    SciTech Connect (OSTI)

    Greenlee, Jordan D. Anderson, Travis J.; Koehler, Andrew D.; Weaver, Bradley D.; Kub, Francis J.; Hobart, Karl D.; Specht, Petra; Dubon, Oscar D.; Luysberg, Martina; Weatherford, Todd R.

    2015-08-24

    Proton-induced damage in AlGaN/GaN HEMTs was investigated using energy-dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM), and simulated using a Monte Carlo technique. The results were correlated to electrical degradation using Hall measurements. It was determined by EDS that the interface between GaN and AlGaN in the irradiated HEMT was broadened by 2.2 nm, as estimated by the width of the Al EDS signal compared to the as-grown interface. The simulation results show a similar Al broadening effect. The extent of interfacial roughening was examined using high resolution TEM. At a 2 MeV proton fluence of 6 × 10{sup 14} H{sup +}/cm{sup 2}, the electrical effects associated with the Al broadening and surface roughening include a degradation of the ON-resistance and a decrease in the electron mobility and 2DEG sheet carrier density by 28.9% and 12.1%, respectively.

  7. Effect of proton irradiation energy on AlGaN/GaN metal-oxide semiconductor high electron mobility transistors

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

    Ahn, S.; Dong, C.; Zhu, W.; Kim, B. -j.; Hwang, Ya-Hsi; Ren, F.; Pearton, S. J.; Yang, Gwangseok; Kim, J.; Patrick, Erin; et al

    2015-08-18

    The effects of proton irradiation energy on dc characteristics of AlGaN/GaN metal-oxide semiconductor high electron mobility transistors (MOSHEMTs) using Al2O3 as the gate dielectric were studied. Al2O3/AlGaN/GaN MOSHEMTs were irradiated with a fixed proton dose of 5 × 1015 cm-2 at different energies of 5, 10, or 15 MeV. More degradation of the device dc characteristics was observed for lower irradiation energy due to the larger amount of nonionizing energy loss in the active region of the MOSHEMTs under these conditions. The reductions in saturation current were 95.3%, 68.3%, and 59.8% and reductions in maximum transconductance were 88%, 54.4%, andmore » 40.7% after 5, 10, and 15 MeV proton irradiation, respectively. Both forward and reverse gate leakage current were reduced more than one order of magnitude after irradiation. The carrier removal rates for the irradiation energies employed in this study were in the range of 127–289 cm-1. These are similar to the values reported for conventional metal-gate high-electron mobility transistors under the same conditions and show that the gate dielectric does not affect the response to proton irradiation for these energies.« less

  8. EIS-0476: Vogtle Electric Generating Plant in Burke County, GA | Department

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

    of Energy 6: Vogtle Electric Generating Plant in Burke County, GA EIS-0476: Vogtle Electric Generating Plant in Burke County, GA February 8, 2012 EIS-0476: Final Environmental Impact Statement Department of Energy Loan Guarantees for Proposed Units 3 and 4 at the Vogtle Electric Generating Plant, Burke County, GA February 25, 2014 EIS-0476: Record of Decision Department of Energy Loan Guarantees for Proposed Units 3 and 4 at the Vogtle Electric Generating Plant, Burke County, GA

  9. GaN Initiative for Grid Applications (GIGA)

    SciTech Connect (OSTI)

    Turner, George

    2015-07-03

    For nearly 4 ½ years, MIT Lincoln Laboratory (MIT/LL) led a very successful, DoE-funded team effort to develop GaN-on-Si materials and devices, targeting high-voltage (>1 kV), high-power, cost-effective electronics for grid applications. This effort, called the GaN Initiative for Grid Applications (GIGA) program, was initially made up of MIT/LL, the MIT campus group of Prof. Tomas Palacios (MIT), and the industrial partner M/A Com Technology Solutions (MTS). Later in the program a 4th team member was added (IQE MA) to provide commercial-scale GaN-on-Si epitaxial materials. A basic premise of the GIGA program was that power electronics, for ubiquitous utilization -even for grid applications - should be closer in cost structure to more conventional Si-based power electronics. For a number of reasons, more established GaN-on-SiC or even SiC-based power electronics are not likely to reach theses cost structures, even in higher manufacturing volumes. An additional premise of the GIGA program was that the technical focus would be on materials and devices suitable for operating at voltages > 1 kV, even though there is also significant commercial interest in developing lower voltage (< 1 kV), cost effective GaN-on-Si devices for higher volume applications, like consumer products. Remarkable technical progress was made during the course of this program. Advances in materials included the growth of high-quality, crack-free epitaxial GaN layers on large-diameter Si substrates with thicknesses up to ~5 μm, overcoming significant challenges in lattice mismatch and thermal expansion differences between Si and GaN in the actual epitaxial growth process. Such thick epilayers are crucial for high voltage operation of lateral geometry devices such as Schottky barrier (SB) diodes and high electron mobility transistors (HEMTs). New “Normally-Off” device architectures were demonstrated – for safe operation of power electronics circuits. The trade-offs between lateral and

  10. Ultrasensitive detection of Hg{sup 2+} using oligonucleotide-functionalized AlGaN/GaN high electron mobility transistor

    SciTech Connect (OSTI)

    Cheng, Junjie; Li, Jiadong; Miao, Bin; Wu, Dongmin; Wang, Jine; Pei, Renjun; Wu, Zhengyan

    2014-08-25

    An oligonucleotide-functionalized ion sensitive AlGaN/GaN high electron mobility transistor (HEMT) was fabricated to detect trace amounts of Hg{sup 2+}. The advantages of ion sensitive AlGaN/GaN HEMT and highly specific binding interaction between Hg{sup 2+} and thymines were combined. The current response of this Hg{sup 2+} ultrasensitive transistor was characterized. The current increased due to the accumulation of Hg{sup 2+} ions on the surface by the highly specific thymine-Hg{sup 2+}-thymine recognition. The dynamic linear range for Hg{sup 2+} detection has been determined in the concentrations from 10{sup −14} to 10{sup −8} M and a detection limit below 10{sup −14} M level was estimated, which is the best result of AlGaN/GaN HEMT biosensors for Hg{sup 2+} detection till now.

  11. An inverted AlGaAs/GaAs patterned-Ge tunnel junction cascade concentrator solar cell. Final subcontract report, 1 January 1991--31 August 1992

    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.

  12. Influence of strain induced by AlN nucleation layer on the electrical properties of AlGaN/GaN heterostructures on Si(111) substrate

    SciTech Connect (OSTI)

    Christy, Dennis; Watanabe, Arata; Egawa, Takashi

    2014-10-15

    The crack-free metal-organic chemical vapor deposition (MOCVD) grown AlGaN/GaN heterostructures on Si substrate with modified growth conditions of AlN nucleation layer (NL) and its influence on the electrical and structural properties of conductive GaN layer are presented. From the Hall electrical measurements, a gradual decrease of two-dimensional electron gas (2DEG) concentration near heterointerface as the function of NL thickness is observed possibly due to the reduction in difference of piezoelectric polarization charge densities between AlGaN and GaN layers. It also indicates that the minimum tensile stress and a relatively less total dislocation density for high pressure grown NL can ensure a 20 % increment in mobility at room temperature irrespective of the interface roughness. The thickness and pressure variations in NL and the subsequent changes in growth mode of AlN contributing to the post growth residual tensile stress are investigated using X-ray diffraction and Raman scattering experiments, respectively. The post growth intrinsic residual stress in top layers of heterostructures arises from lattice mismatches, NL parameters and defect densities in GaN. Hence, efforts to reduce the intrinsic residual stress in current conducting GaN layer give an opportunity to further improve the electrical characteristics of AlGaN/GaN device structures on Si.

  13. Absorption enhancement through Fabry-Prot resonant modes in a 430?nm thick InGaAs/GaAsP multiple quantum wells solar cell

    SciTech Connect (OSTI)

    Behaghel, B.; Tamaki, R.; Watanabe, K.; Sodabanlu, H.; Vandamme, N.; Dupuis, C.; Bardou, N.; Cattoni, A.; Okada, Y.; Sugiyama, M.; Collin, S.; Guillemoles, J.-F.

    2015-02-23

    We study light management in a 430?nm-thick GaAs p-i-n single junction solar cell with 10 pairs of InGaAs/GaAsP multiple quantum wells (MQWs). The epitaxial layer transfer on a gold mirror improves light absorption and increases the external quantum efficiency below GaAs bandgap by a factor of four through the excitation of Fabry-Perot resonances. We show a good agreement with optical simulation and achieve around 10% conversion efficiency. We demonstrate numerically that this promising result can be further improved by anti-reflection layers. This study paves the way to very thin MQWs solar cells.

  14. In-plane tunneling anisotropic magnetoresistance in (Ga,Mn)As/GaAs Esaki diodes in the regime of the excess current

    SciTech Connect (OSTI)

    Shiogai, J.; Ciorga, M. Utz, M.; Schuh, D.; Bougeard, D.; Weiss, D.; Kohda, M.; Nitta, J.; Nojima, T.

    2015-06-29

    We investigate the angular dependence of the tunneling anisotropic magnetoresistance in (Ga,Mn)As/n-GaAs spin Esaki diodes in the regime where the tunneling process is dominated by the excess current through midgap states in (Ga,Mn)As. We compare it to similar measurements performed in the regime of band-to-band tunneling. Whereas the latter show biaxial symmetry typical for magnetic anisotropy observed in (Ga,Mn)As samples, the former is dominated by uniaxial anisotropy along the 〈110〉 axes.

  15. Selective saturation of paramagnetic defects in electron- and neutron-irradiated GaAs

    SciTech Connect (OSTI)

    Goltzene, A.; Meyer, B.; Schwab, C.; Beall, R.B.; Newman, R.C.; Whitehouse, J.E.; Woodhead, J.

    1985-06-15

    A comparison of the electron paramagnetic resonance spectra obtained in fast neutron- and electron-irradiated GaAs crystals has confirmed the simultaneous presence of the quadruplet and singlet spectra, ascribed previously to As/sup 4 +//sub Ga/ and V/sup 2 -//sub Ga/ centers. Only in electron-irradiated material, however, are both signals separated by the selective microwave power saturation of the quadruplet. This apparent disparity is ascribed to a difference in the coupling between the two partners in the As/sup 4 +//sub Ga/-V/sup 2 -//sub Ga/ associated complexes.

  16. Ultra High p-doping Material Research for GaN Based Light Emitters

    SciTech Connect (OSTI)

    Vladimir Dmitriev

    2007-06-30

    The main goal of the Project is to investigate doping mechanisms in p-type GaN and AlGaN and controllably fabricate ultra high doped p-GaN materials and epitaxial structures. Highly doped p-type GaN-based materials with low electrical resistivity and abrupt doping profiles are of great importance for efficient light emitters for solid state lighting (SSL) applications. Cost-effective hydride vapor phase epitaxial (HVPE) technology was proposed to investigate and develop p-GaN materials for SSL. High p-type doping is required to improve (i) carrier injection efficiency in light emitting p-n junctions that will result in increasing of light emitting efficiency, (ii) current spreading in light emitting structures that will improve external quantum efficiency, and (iii) parameters of Ohmic contacts to reduce operating voltage and tolerate higher forward currents needed for the high output power operation of light emitters. Highly doped p-type GaN layers and AlGaN/GaN heterostructures with low electrical resistivity will lead to novel device and contact metallization designs for high-power high efficiency GaN-based light emitters. Overall, highly doped p-GaN is a key element to develop light emitting devices for the DOE SSL program. The project was focused on material research for highly doped p-type GaN materials and device structures for applications in high performance light emitters for general illumination P-GaN and p-AlGaN layers and multi-layer structures were grown by HVPE and investigated in terms of surface morphology and structure, doping concentrations and profiles, optical, electrical, and structural properties. Tasks of the project were successfully accomplished. Highly doped GaN materials with p-type conductivity were fabricated. As-grown GaN layers had concentration N{sub a}-N{sub d} as high as 3 x 10{sup 19} cm{sup -3}. Mechanisms of doping were investigated and results of material studies were reported at several International conferences providing

  17. Conductivity based on selective etch for GaN devices and applications thereof

    DOE Patents [OSTI]

    Zhang, Yu; Sun, Qian; Han, Jung

    2015-12-08

    This invention relates to methods of generating NP gallium nitride (GaN) across large areas (>1 cm.sup.2) with controlled pore diameters, pore density, and porosity. Also disclosed are methods of generating novel optoelectronic devices based on porous GaN. Additionally a layer transfer scheme to separate and create free-standing crystalline GaN thin layers is disclosed that enables a new device manufacturing paradigm involving substrate recycling. Other disclosed embodiments of this invention relate to fabrication of GaN based nanocrystals and the use of NP GaN electrodes for electrolysis, water splitting, or photosynthetic process applications.

  18. Method of plasma etching Ga-based compound semiconductors

    SciTech Connect (OSTI)

    Qiu, Weibin; Goddard, Lynford L.

    2012-12-25

    A method of plasma etching Ga-based compound semiconductors includes providing a process chamber and a source electrode adjacent to the process chamber. The process chamber contains a sample comprising a Ga-based compound semiconductor. The sample is in contact with a platen which is electrically connected to a first power supply, and the source electrode is electrically connected to a second power supply. The method includes flowing SiCl.sub.4 gas into the chamber, flowing Ar gas into the chamber, and flowing H.sub.2 gas into the chamber. RF power is supplied independently to the source electrode and the platen. A plasma is generated based on the gases in the process chamber, and regions of a surface of the sample adjacent to one or more masked portions of the surface are etched to create a substantially smooth etched surface including features having substantially vertical walls beneath the masked portions.

  19. Method of plasma etching GA-based compound semiconductors

    DOE Patents [OSTI]

    Qiu, Weibin; Goddard, Lynford L.

    2013-01-01

    A method of plasma etching Ga-based compound semiconductors includes providing a process chamber and a source electrode adjacent thereto. The chamber contains a Ga-based compound semiconductor sample in contact with a platen which is electrically connected to a first power supply, and the source electrode is electrically connected to a second power supply. SiCl.sub.4 and Ar gases are flowed into the chamber. RF power is supplied to the platen at a first power level, and RF power is supplied to the source electrode. A plasma is generated. Then, RF power is supplied to the platen at a second power level lower than the first power level and no greater than about 30 W. Regions of a surface of the sample adjacent to one or more masked portions of the surface are etched at a rate of no more than about 25 nm/min to create a substantially smooth etched surface.

  20. AlGaAs diode pumped tunable chromium lasers

    DOE Patents [OSTI]

    Krupke, William F.; Payne, Stephen A.

    1992-01-01

    An all-solid-state laser system is disclosed wherein the laser is pumped in the longwave wing of the pump absorption band. By utilizing a laser material that will accept unusually high dopant concentrations without deleterious effects on the crystal lattice one is able to compensate for the decreased cross section in the wing of the absorption band, and the number of pump sources which can be used with such a material increases correspondingly. In a particular embodiment a chromium doped colquiriite-structure crystal such as Cr:LiSrAlF.sub.6 is the laser material. The invention avoids the problems associated with using AlGaInP diodes by doping the Cr:LiSrAlF.sub.6 heavily to enable efficient pumping in the longwave wing of the absorption band with more practical AlGaAs diodes.