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Sample records for hall town hall

  1. WORKFORCE DIVERSITY TOWN HALL

    Energy Savers [EERE]

    ... fracturing our communities." Secretary Hillary Rodham Clinton WORKFORCE DIVERSITY TOWN HALL Agenda I. Welcome Mel Williams, Jr., Associate Deputy Secretary II. Opening Remarks Dr. ...

  2. Town Hall Questions Answered

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

    8, 2014 CBFO Manager's weekly update to local residents Read Carlsbad Field Office Manager Joe Franco's letter to Eddy and Lea County residents for the week of April 14: at http://1.usa.gov/1mkxm7b Town Hall Questions Answered Q. What is the condition of Panel 7 right now? A. Work teams entering the underground facility as part of ongoing Phase 3 activities are still working to determine the full condition of Panel 7. Initial entries indicate good roof conditions. Q. What's the presumed reason

  3. Science and Energy Town Hall

    Broader source: Energy.gov [DOE]

    Watch a live broadcast of the Science & Energy Town Hall on Wednesday, January 20, 2016 from 2:30 p.m. to 3:30 p.m. EST.

  4. Sec. Chu Online Town Hall

    Office of Energy Efficiency and Renewable Energy (EERE)

    Secretary Steven Chu hosted an online town hall to discuss the clean energy and innovation agenda President Obama laid out in his 2011 State of the Union address. (January 26, 2011)

  5. Town Hall meeting | OpenEI Community

    Open Energy Info (EERE)

    picture Submitted by Graham7781(2017) Super contributor 16 November, 2012 - 11:23 LEDS the focus of Monday's 10 a.m. Town Hall Meeting LEDS Town Hall meeting What: OpenEI's...

  6. Town Hall with Secretary Moniz

    ScienceCinema (OSTI)

    Energy Secretary Ernest Moniz; Deputy Secretary of Energy Daniel Poneman

    2013-07-25

    In a town hall meeting with Department staff, Energy Secretary Ernest Moniz spoke about his plans for a reorganization of the Energy Department?s management structure. The plans will help better achieve the Department?s key priorities and those of the President, including implementing the President?s Climate Action Plan, ?all of the above? energy strategy and nuclear security agenda. After his remarks, Moniz, joined by Deputy Secretary Dan Poneman, took questions from the audience in the Forrestal Auditorium as well as email questions from other Department locations.

  7. Town Hall with Secretary Moniz

    SciTech Connect (OSTI)

    Energy Secretary Ernest Moniz; Deputy Secretary of Energy Daniel Poneman

    2013-07-18

    In a town hall meeting with Department staff, Energy Secretary Ernest Moniz spoke about his plans for a reorganization of the Energy Department’s management structure. The plans will help better achieve the Department’s key priorities and those of the President, including implementing the President’s Climate Action Plan, “all of the above” energy strategy and nuclear security agenda. After his remarks, Moniz, joined by Deputy Secretary Dan Poneman, took questions from the audience in the Forrestal Auditorium as well as email questions from other Department locations.

  8. OSDBU Federal Contracting Town Hall Meeting

    Office of Energy Efficiency and Renewable Energy (EERE)

    In June of 2015, John Hale III, Director of the Office of Small and Disadvantaged Business Utilization, served as the moderator for the Federal Contracting Town Hall Meeting during the CelebrAsian...

  9. Diversity and Inclusion Town Hall Program Book | Department of Energy

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

    Town Hall Program Book Diversity and Inclusion Town Hall Program Book As part of a larger effort to create a culture that values diversity, we have been conducting focus groups to engage in a dialog and hear feedback on how diversity can be improved. At the Town Hall, DOE employees will hear the results of these discussions. View the program booklet from the Diversity and Inclusion Town Hall below. For more information about the Department's diversity and inclusion programs, visit

  10. Town_Hall_Meeting_10_29_15.pdf

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

    Town Hall with Secretary Moniz Town Hall with Secretary Moniz July 18, 2013 - 3:42pm Addthis Secretary Moniz speaks at a townhall with DOE employees on the Departmental reorganization. Dan Leistikow Dan Leistikow Former Director, Office of Public Affairs In a town hall meeting with Department staff, Energy Secretary Ernest Moniz spoke about his plans for a reorganization of the Energy Department's management structure. The plans will help better achieve the Department's key priorities and those

  11. Webcast: National Energy Literacy Virtual Town Hall | Department of Energy

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

    Webcast: National Energy Literacy Virtual Town Hall Webcast: National Energy Literacy Virtual Town Hall Webcast: National Energy Literacy Virtual Town Hall On August 5, 2014, the Department of Energy (DOE) hosted a dynamic virtual conversation of ongoing efforts from across the country in utilizing the Energy Literacy Framework to address one of our nations' biggest national challenges, "Energy Illiteracy." The goal of this webinar was to share resources in energy education and provide

  12. Missed Today's Town Hall with Sec. Chu? | Department of Energy

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

    Missed Today's Town Hall with Sec. Chu? Missed Today's Town Hall with Sec. Chu? January 26, 2011 - 4:02pm Addthis We have the video of today's online town hall event with Secretary Chu up and ready for your viewing. Check it out here. Ginny Simmons Ginny Simmons Former Managing Editor for Energy.gov, Office of Public Affairs We have the video of today's online town hall event with Secretary Chu up and ready for your viewing. Check it out here. During the event, Secretary Chu highlighted several

  13. Town Hall with Secretary Moniz | Department of Energy

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

    Secretary Moniz speaks at a townhall with DOE employees on the Departmental ... In a town hall meeting with Department staff, Energy Secretary Ernest Moniz spoke about ...

  14. OpenEI Community - Town Hall meeting

    Open Energy Info (EERE)

    st, 2012 http:en.openei.orgcommunityblogtown-hall-meeting-october-1st-2012

  15. SubTER Presentation at Town Hall- American Geophysical Union

    Broader source: Energy.gov [DOE]

    Subter, the Subsurface Crosscut at the Energy Department, conducted a Town Hall meeting to share information and create a dialogue regarding the grand challenges of energy production and storage in the subsurface.

  16. Public invited to LANL-sponsored Energy Town Hall

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

    Day event showcases LANL energy work April 19, 2010 Public invited to LANL-sponsored Energy Town Hall April 21 at the J. Robert Oppenheimer Study Center LOS ALAMOS, New Mexico, April 19, 2010-The public is invited to learn about projects in energy conservation, generation, research, and management at an Energy Town Hall April 21. Other energy-related issues, such as server virtualization, solar energy, and Los Alamos National Laboratory's perspective on renewable energy, also will be explored in

  17. 06.27.14 SRS Retirees Town Hall Meeting-Dave Hepner Page...

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

    Meeting-Dave Hepner Page 1 SRSRA TOWN HALL MEETING New Ellenton Community Center JUNE 27, 2014 After reviewing the notes and discussing the Town Hall Meeting held on June 27, 2014,...

  18. AGU SubTER Town Hall Presentation 2015 | Department of Energy

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

    AGU SubTER Town Hall Presentation 2015 AGU SubTER Town Hall Presentation 2015 AGU SubTER Townhall 2015.pdf (4.49 MB) More Documents & Publications SubTER Presentation at Town Hall - American Geophysical Union Poster on Subsurface Technology & Engineering Research, Development, and Demonstration Crosscut (SubTER) Controlling Subsurface Fractures and Fluid Flow: A Basic Research Agenda

  19. Town Hall Meeting October 1st, 2012 | OpenEI Community

    Open Energy Info (EERE)

    Town Hall Meeting October 1st, 2012 Home > Blogs > Graham7781's blog Graham7781's picture Submitted by Graham7781(2017) Super contributor 19 September, 2012 - 13:40 OpenEI Town...

  20. President Obama Talks Clean Energy At Facebook Town Hall | Department of

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

    Energy At Facebook Town Hall President Obama Talks Clean Energy At Facebook Town Hall April 25, 2011 - 10:24am Addthis Ginny Simmons Ginny Simmons Former Managing Editor for Energy.gov, Office of Public Affairs What does this mean for me? We are investing in new technologies that will help us reduce our dependence on fossil fuels. By investing in STEM education, we are investing in our future. President Obama hosted a town hall at Facebook's headquarters last Wednesday to discuss the

  1. LEDS the focus of Monday's 10 a.m. Town Hall Meeting | OpenEI...

    Open Energy Info (EERE)

    LEDS the focus of Monday's 10 a.m. Town Hall Meeting Home > Blogs > Graham7781's blog Graham7781's picture Submitted by Graham7781(2017) Super contributor 16 November, 2012 - 11:23...

  2. Newport News School Board Member Hosting Town Hall Thursday (Daily Press) |

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

    Jefferson Lab Newport News School Board Member Hosting Town Hall Thursday (Daily Press) External Link: http://articles.dailypress.com/2012-03-05/news/dp-nws-ednotebook-0305-20120304_1... By jlab_admin on Tue, 2012-03-06

  3. 06.27.14 SRS Retirees Town Hall Meeting Q/A Period Summary Page 1

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

    Meeting Q/A Period Summary Page 1 NOTICE: SRSRA TOWN HALL MEETING QUESTION/ANSWER PERIOD SUMMARY New Ellenton Community Center JUNE 27, 2014 *105 in Attendance *Meeting Agenda & Handout available  Dave Moody, DOE-SR Manager  John Veldman, SRS Retirees Association (SRSRA) Board  Dave Hepner, DOE-SR Acquisitions Operations Division Director  Carol Barry, SRNS Benefits Q: Why are their 2 columns on the chart (referencing handout)? A: Left column is ERISA minimum, which is the

  4. Microsoft PowerPoint - Town Hall Slides 5-15-14 rev.0

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

    15, 2014 Meeting Agenda * Opening Comments - Mayor Janway * Panel Member Introductions - John Heaton (Moderator) * CBFO Manager Remarks - Dana Bryson * Update on Phase 3 Activities - Tammy Reynolds * May 10 Entry * Today's Entry * Ventilation System Status * Close-out of Bioassay Program - Jim Stafford * Audience Questions * One question at a time please OPENING COMMENTS Dana Bryson, CBFO Deputy Manager This Week's Events * Joe Franco in Washington * Town Hall Agenda * May 10 and May 15 Entries

  5. Microsoft PowerPoint - Town_Hall_Slides_3_5_15_Final

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

    Carlsbad Town Hall Meeting Sponsored by the U.S. Department of Energy and the City of Carlsbad, NM March 5, 2015 www.energy.gov/EM 2 Agenda * Opening Comments - Mayor Dale Janway * Update on CBFO and WIPP activities - Dana Bryson * Recovery Status - Tammy Reynolds * Radiological Contamination - Jim Blankenhorn * Audience Questions * In house * Internet * Closing Comments - Dana Bryson www.energy.gov/EM 3 Update on CBFO and WIPP Activities Dana Bryson, CBFO Deputy Manager www.energy.gov/EM 4 *

  6. Tune In To Our Online Town Hall With Sec. Chu at 12:45PM EST | Department

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

    of Energy Tune In To Our Online Town Hall With Sec. Chu at 12:45PM EST Tune In To Our Online Town Hall With Sec. Chu at 12:45PM EST January 26, 2011 - 8:35am Addthis Ginny Simmons Ginny Simmons Former Managing Editor for Energy.gov, Office of Public Affairs During the State of the Union address last night, President Obama placed the national spotlight on clean energy, saying that "we need to out-innovate, out-educate, and out-build the rest of the world," and that we must invest in

  7. Miles Hall

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

    Miles Hall - 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 Waste Management Programs Advanced Nuclear Energy

  8. Fermilab Wilson Hall and Vicinity

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

    Wilson Hall and Vicinity Wilson Hall Ramsey Auditorium Booster Linac Antiproton Source Leon M. Lederman Science Education Center...

  9. Jefferson Lab Experimental Hall D

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

    D Privacy and Security Notice Skip over navigation search Group This site's design is only visible in a graphical browser that supports web standards, but its content is accessible to any browser. Concerns? Hall D Navigation Hall D Main Hall D Engineering Hall D Staff Hall D Safety print version Hall D in October 2014 Related Links CEBAF at 12 GEV JLab Visitor's Center JLab Virtual Tour JLab page for scientists Experimental Hall A Experimental Hall B Experimental Hall C Hall D Task List - HDList

  10. Mary Hall Salishan

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

    From Hall et al, "Maximizing Multiprocessor Performance with the SUIF Compiler", IEEE Computer, Dec. 1996. 50% higher Specfp95 ratio than previously reported 3 1990s View *...

  11. Microsoft PowerPoint - SRSCRO Public Town Hall Mtg - SRS Missions & Funding FY 14 & 15 - 17 Apr 14.ppt [Repaired]

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

    This image cannot currently be displayed. This image cannot currently be displayed. Savannah River Site Missions, Accomplishments and Funding SRS Community Reuse Organization Public Town Hall Meeting April 17, 2014 Dr. Dave Moody Site Manager DOE-Savannah River Doug Hintze Assistant Manager for Mission Support/Acting Chief Financial Officer DOE-Savannah River This image cannot currently be displayed. www.energy.gov/EM This image cannot currently be displayed. Purpose Ø Provide an overview of

  12. Hall A Annual Report 2013

    SciTech Connect (OSTI)

    Dalton, Mark M.

    2014-02-01

    Report over the experimental activities in Hall A at Thomas Jefferson National Accelerator Facility during 2013.

  13. Hall Ammendment Policy

    Broader source: Energy.gov [DOE]

    Joint statement providing interim policy on processing proposals for leasing DOE real property using the authority in 42 U.S.C. 7256, commonly referred to as the "Hall Amendment."

  14. Jefferson Lab Experimental Hall B

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

    Hall B Privacy and Security Notice Skip over navigation search Group Please upgrade your browser. This site's design is only visible in a graphical browser that supports web standards, but its content is accessible to any browser. Concerns? Hall B Navigation Hall B Main CLAS CLAS12 Other Expts Run Info Publications Public Interest print version Hall B Main CLAS Collaboration and Hall B CLAS Collaboration Information Phonebook, Opt-in, and Database Reviews and Service Work Login Working Groups

  15. Unconventional Quantum Hall Effect and Tunable Spin Hall Effect...

    Office of Scientific and Technical Information (OSTI)

    to an Isolated MoS2 Trilayer Title: Unconventional Quantum Hall Effect and Tunable Spin Hall Effect in Dirac Materials: Application to an Isolated MoS2 Trilayer Authors: Li, ...

  16. Experimental Hall C | Jefferson Lab

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

    C Jefferson Lab has four experimental halls. Hall C is 150 feet in diameter and 60 feet tall. Hall C houses a High Momentum Spectrometer and provides space for large-installation experiments. These are stand-alone experiments requiring unique or highly specialized detectors, magnets and targeting systems. The research equipment in Hall C is used to study the weak charge of the proton, form factors of simple quark systems, the transition from hadrons to quarks and nuclei with a strange quark

  17. Workforce Diversity Town Hall

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

    2011-08-18

    On August 18, 2011, President Obama issued an Executive Order, "Establishing a Coordinated Government-wide Initiative to Promote Diversity and Inclusion in the Federal Workforce," directing federal agencies to develop strategic plans to recruit and retain a more diverse workforce.

  18. Modeling the Hall Thruster

    SciTech Connect (OSTI)

    Fisch, N.J.; Fruchtman, A.

    1998-08-01

    The acceleration of the plasma in the Hall thruster to supersonic velocities is examined by the use of a steady state model. Flows that are smooth across the sonic transition plane are found. The possibility of generating flows in which the acceleration across the sonic plane is abrupt, is also studied.

  19. Experimental Hall A | Jefferson Lab

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

    A Jefferson Lab has four experimental halls. Hall A is the largest of these four experimental staging areas. It is 174 feet across and 80 feet tall from the floor to the highest spot on its domed ceiling. The foundation for the hall is 35 feet below ground. Hall A is outfitted with two primary detector systems - both high-resolution spectrometers, each weighing about 3 million pounds or 1,500 short tons. The hall is used primarily for experiments that study the structure of the nucleus and the

  20. Cylindrical geometry hall thruster

    DOE Patents [OSTI]

    Raitses, Yevgeny; Fisch, Nathaniel J.

    2002-01-01

    An apparatus and method for thrusting plasma, utilizing a Hall thruster with a cylindrical geometry, wherein ions are accelerated in substantially the axial direction. The apparatus is suitable for operation at low power. It employs small size thruster components, including a ceramic channel, with the center pole piece of the conventional annular design thruster eliminated or greatly reduced. Efficient operation is accomplished through magnetic fields with a substantial radial component. The propellant gas is ionized at an optimal location in the thruster. A further improvement is accomplished by segmented electrodes, which produce localized voltage drops within the thruster at optimally prescribed locations. The apparatus differs from a conventional Hall thruster, which has an annular geometry, not well suited to scaling to small size, because the small size for an annular design has a great deal of surface area relative to the volume.

  1. Experimental Hall B | Jefferson Lab

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

    and electromagnetic calorimeters for electron and neutral particle identification. Major research programs in Hall B include experiments to measure the spectrum of excited ...

  2. ARM - Welcome to Study Hall

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

    Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox ...

  3. Directions to Wilson Hall, Fermilab

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

    in Wilson Hall, the central laboratory building of Fermi National Accelerator Laboratory, as shown on the map below. Ramsey Auditorium is located at the south end of Wilson ...

  4. Experimental Hall B | Jefferson Lab

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

    B Jefferson Lab has four experimental halls. Hall B is the smallest of the experimental staging areas. It is 98 feet in diameter and 65 feet from floor to ceiling. Experiments that take data in Hall B employ beams of either electrons or photons. From 1995 to 2012, the heart of the Hall B physics program involved the use of the CEBAF Large Acceptance Spectrometer, or CLAS. This detector system spanned nearly the full angular range about the target and was specifically developed for the study of

  5. Experimental Hall D | Jefferson Lab

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

    D A fourth experimental hall, known as Hall D, is currently under construction and is scheduled to begin experiments in 2015. The Hall D project consists of an extension to the accelerator tunnel to house a new beam transport line, a dedicated magnet to tag photons created in beam-target interactions, a counting house, cryogenics plant and service buildings. When it is completed, Hall D will make it possible for scientists to study what are known as exotic mesons or hybrids. You can learn more

  6. Forest County Potawatomi Community Wundar Hall Project

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

    ... Wundar Hall Project Wundar Hall is a 34,000 sq ft building located on the former ... by the Tribe and taken into Trust in 1990. Wundar Hall is currently not in use. ...

  7. QER- Comment of Addison Hall

    Broader source: Energy.gov [DOE]

    I and my family own land in Ashfield next to the proposed Kinder Morgan/Tennessee Pipeline route. We are opposed to the pipeline for a variety of reasons, including the highly questionable need for the proposed commodity increase and the inevitable damage to the environment and communities along the proposed route. Addison Hall for the Hall Family Trust.

  8. Anthony Kathryn Hall | Open Energy Information

    Open Energy Info (EERE)

    Anthony Kathryn Hall Jump to: navigation, search Name: Anthony & Kathryn Hall Place: United Kingdom Sector: Wind energy Product: UK-based private wind farm in Highland. References:...

  9. Second Generation Fractional Quantum Hall Effect

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

    Generation Fractional Quantum Hall Effect - Sandia Energy Energy Search Icon Sandia Home ... Second Generation Fractional Quantum Hall Effect HomeHighlights - Energy Research...

  10. Tuning giant anomalous Hall resistance ratio in perpendicular Hall balance

    SciTech Connect (OSTI)

    Zhang, J. Y.; Yang, G.; Wang, S. G. E-mail: ghyu@mater.ustb.edu.cn; Liu, J. L.; Wang, R. M.; Amsellem, E.; Kohn, A.; Yu, G. H. E-mail: ghyu@mater.ustb.edu.cn

    2015-04-13

    Anomalous Hall effect at room temperature in perpendicular Hall balance with a core structure of [Pt/Co]{sub 4}/NiO/[Co/Pt]{sub 4} has been tuned by functional CoO layers, where [Pt/Co]{sub 4} multilayers exhibit perpendicular magnetic anisotropy. A giant Hall resistance ratio up to 69 900% and saturation Hall resistance (R{sub S}{sup P}) up to 2590 mΩ were obtained in CoO/[Pt/Co]{sub 4}/NiO/[Co/Pt]{sub 4}/CoO system, which is 302% and 146% larger than that in the structure without CoO layers, respectively. Transmission electron microscopy shows highly textured [Co/Pt]{sub 4} multilayers and oxide layers with local epitaxial relations, indicating that the crystallographic structure has significant influence on spin dependent transport properties.

  11. Experimental Hall C | Jefferson Lab

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

    in Hall C is used to study the weak charge of the proton, form factors of simple quark systems, the transition from hadrons to quarks and nuclei with a strange quark embedded....

  12. Optimization of Cylindrical Hall Thrusters

    SciTech Connect (OSTI)

    Yevgeny Raitses, Artem Smirnov, Erik Granstedt, and Nathaniel J. Fi

    2007-07-24

    The cylindrical Hall thruster features high ionization efficiency, quiet operation, and ion acceleration in a large volume-to-surface ratio channel with performance comparable with the state-of-the-art annular Hall thrusters. These characteristics were demonstrated in low and medium power ranges. Optimization of miniaturized cylindrical thrusters led to performance improvements in the 50-200W input power range, including plume narrowing, increased thruster efficiency, reliable discharge initiation, and stable operation. __________________________________________________

  13. Optimization of Cylindrical Hall Thrusters

    SciTech Connect (OSTI)

    Yevgeny Raitses, Artem Smirnov, Erik Granstedt, and Nathaniel J. Fisch

    2007-11-27

    The cylindrical Hall thruster features high ionization efficiency, quiet operation, and ion acceleration in a large volume-to-surface ratio channel with performance comparable with the state-of-the-art annular Hall thrusters. These characteristics were demonstrated in low and medium power ranges. Optimization of miniaturized cylindrical thrusters led to performance improvements in the 50-200W input power range, including plume narrowing, increased thruster efficiency, reliable discharge initiation, and stable operation.

  14. Spin Hall controlled magnonic microwaveguides

    SciTech Connect (OSTI)

    Demidov, V. E.; Urazhdin, S.; Rinkevich, A. B.; Reiss, G.; Demokritov, S. O.

    2014-04-14

    We use space-resolved magneto-optical spectroscopy to study the influence of spin Hall effect on the excitation and propagation of spin waves in microscopic magnonic waveguides. We find that the spin Hall effect not only increases the spin-wave propagation length, but also results in an increased excitation efficiency due to the increase of the dynamic susceptibility in the vicinity of the inductive antenna. We show that the efficiency of the propagation length enhancement is strongly dependant on the type of the excited spin-wave mode and its wavelength.

  15. Jefferson Lab Experimental Hall C

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

    C Privacy and Security Notice Skip over navigation search Group This site's design is only visible in a graphical browser that supports web standards, but its content is accessible to any browser. Concerns? Hall C Navigation Users Public Interest print version HES, HKS and Splitter Qweak spectrometer used to measure proton weak charge 12 GeV Upgrade Upgrade information 12 GeV Experiments SHMS-HMS User's Group User's Group mailing list Newsletter 12 GeV wiki Hall C Collaboration Information

  16. The fluctuation induced Hall effect

    SciTech Connect (OSTI)

    Shen, W.; Prager, S.C.

    1993-02-01

    The fluctuation induced Hall term, [le][approximately][ovr J] [times] [approximately][ovr B][ge], has been measured in the MST reversed field pinch. The term is of interest as a possible source of current self-generation (dynamo). It is found to be non-negligible, but small in that it can account for less than 25% of the dynamo driven current.

  17. The fluctuation induced Hall effect

    SciTech Connect (OSTI)

    Shen, W.; Prager, S.C.

    1993-02-01

    The fluctuation induced Hall term, {le}{approximately}{ovr J} {times} {approximately}{ovr B}{ge}, has been measured in the MST reversed field pinch. The term is of interest as a possible source of current self-generation (dynamo). It is found to be non-negligible, but small in that it can account for less than 25% of the dynamo driven current.

  18. Henderson Hall's Education and Career Fair

    Broader source: Energy.gov [DOE]

    Location: Smith Gym, Henderson Hall, Arlington, VAPOC: Donna FriendWebsite: http://www.mccshh.com/EducationCareerFairFall2014.html

  19. Building Green in Greensburg: City Hall Building

    Broader source: Energy.gov [DOE]

    This poster highlights energy efficiency, renewable energy, and sustainable features of the high-performing City Hall building in Greensburg, Kansas.

  20. Rebuilding It Better: Greensburg, Kansas, City Hall

    SciTech Connect (OSTI)

    D. Egan

    2010-04-13

    This document showcases the LEED-Platinum designed Greensburg City Hall, which was rebuilt green, after a massive tornado destroyed Greensburg, Kansas in May 2007.

  1. Hall-effect arc protector

    DOE Patents [OSTI]

    Rankin, Richard A.; Kotter, Dale K.

    1997-01-01

    The Hall-Effect Arc Protector is used to protect sensitive electronics from high energy arcs. The apparatus detects arcs by monitoring an electrical conductor, of the instrument, for changes in the electromagnetic field surrounding the conductor which would be indicative of a possible arcing condition. When the magnitude of the monitored electromagnetic field exceeds a predetermined threshold, the potential for an instrument damaging are exists and the control system logic activates a high speed circuit breaker. The activation of the breaker shunts the energy imparted to the input signal through a dummy load to the ground. After the arc condition is terminated, the normal signal path is restored.

  2. Hall-effect arc protector

    DOE Patents [OSTI]

    Rankin, R.A.; Kotter, D.K.

    1997-05-13

    The Hall-Effect Arc Protector is used to protect sensitive electronics from high energy arcs. The apparatus detects arcs by monitoring an electrical conductor, of the instrument, for changes in the electromagnetic field surrounding the conductor which would be indicative of a possible arcing condition. When the magnitude of the monitored electromagnetic field exceeds a predetermined threshold, the potential for an instrument damaging are exists and the control system logic activates a high speed circuit breaker. The activation of the breaker shunts the energy imparted to the input signal through a dummy load to the ground. After the arc condition is terminated, the normal signal path is restored. 2 figs.

  3. Portland State University Shattuck Hall

    High Performance Buildings Database

    Portland, OR Portland State's Shattuck hall was originally constructed as an elementary school in 1915. In 2007 the university undertook extensive renovations of the building to bring it up to current seismic requirements. In addition to structural improvements, the design team was able to upgraded the building's aging mechanical and electrical systems, upgrade plumbing, and restore the large light wells that bring daylight into the U-shaped building. The resulting building houses Portland State's Architecture department, where students are able to learn from the exposed building systems.

  4. Charge carrier coherence and Hall effect in organic semiconductors...

    Office of Scientific and Technical Information (OSTI)

    Charge carrier coherence and Hall effect in organic semiconductors Citation Details In-Document Search Title: Charge carrier coherence and Hall effect in organic semiconductors ...

  5. Quantum Hall effects in a Weyl semimetal: Possible application...

    Office of Scientific and Technical Information (OSTI)

    Quantum Hall effects in a Weyl semimetal: Possible application in pyrochlore iridates Title: Quantum Hall effects in a Weyl semimetal: Possible application in pyrochlore iridates ...

  6. Reduced spin-Hall effects from magnetic proximity (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Reduced spin-Hall effects from magnetic proximity Prev Next Title: Reduced spin-Hall effects from magnetic proximity Authors: Zhang, Wei ; Jungfleisch, Matthias B. ; Jiang, ...

  7. Topological Hubbard Model and Its High-Temperature Quantum Hall...

    Office of Scientific and Technical Information (OSTI)

    Topological Hubbard Model and Its High-Temperature Quantum Hall Effect Title: Topological Hubbard Model and Its High-Temperature Quantum Hall Effect Authors: Neupert, Titus ; ...

  8. Data acquisition system of Moeller polarimeter Hall A Jefferson...

    Office of Scientific and Technical Information (OSTI)

    Data acquisition system of Moeller polarimeter Hall A Jefferson Lab (in Russian) Citation Details In-Document Search Title: Data acquisition system of Moeller polarimeter Hall A ...

  9. Building America Top Innovations Hall of Fame Profile - Building...

    Energy Savers [EERE]

    Building America Top Innovations Hall of Fame Profile - Building Energy Optimization Analysis Method (BEopt) Building America Top Innovations Hall of Fame Profile - Building Energy...

  10. Microscopic theory of quantum anomalous Hall effect in graphene...

    Office of Scientific and Technical Information (OSTI)

    Microscopic theory of quantum anomalous Hall effect in graphene Citation Details In-Document Search Title: Microscopic theory of quantum anomalous Hall effect in graphene Authors: ...

  11. Hall County, Texas: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    B. Places in Hall County, Texas Estelline, Texas Lakeview, Texas Memphis, Texas Turkey, Texas Retrieved from "http:en.openei.orgwindex.php?titleHallCounty,Texas&oldid...

  12. The quantum Hall effect helicity

    SciTech Connect (OSTI)

    Shrivastava, Keshav N.

    2015-04-16

    The quantum Hall effect in semiconductor heterostructures is explained by two signs in the angular momentum j=l±s and g=(2j+1)/(2l+1) along with the Landau factor (n+1/2). These modifications in the existing theories explain all of the fractional charges. The helicity which is the sign of the product of the linear momentum with the spin p.s plays an important role for the understanding of the data at high magnetic fields. In particular it is found that particles with positive sign in the spin move in one direction and those with negative sign move in another direction which explains the up and down stream motion of the particles.

  13. Experiment Hall & Beamline | Advanced Photon Source

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

    1104-m-circumference optical bench. The hall floor is made of 1-ft-thick poured concrete. Usual practice in poured concrete construction is the use of evenly spaced cuts in...

  14. DOE2016 Exhibit Hall | Department of Energy

    Energy Savers [EERE]

    Exhibit Hall DOE2016 Exhibit Hall Addthis 1 of 25 2 of 25 3 of 25 4 of 25 5 of 25 6 of 25 7 of 25 8 of 25 9 of 25 10 of 25 11 of 25 12 of 25 13 of 25 14 of 25 15 of 25 16 of 25 17 of 25 18 of 25 19 of 25 20 of 25 21 of 25 22 of 25 23 of 25 24 of 25 25 of 25

  15. Hypernuclei in Hall C | Jefferson Lab

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

    Hypernuclei in Hall C Hypernuclei in Hall C High Resolution Electron Spectrometer The High Resolution Electron Spectrometer (teal and red, top left) was recently built with a grant from Japan's Ministry of Education, Culture, Sports, Science and Technology. The ministry also funded the new splitter magnet (dark green) and the High Resolution Kaon Spectrometer (purple and light green, top right). Nuclear scientists have gone to great lengths to pry open the nucleus and peer deep inside. They've

  16. Forest County Potawatomi Community Parking Ramp and Wundar Hall...

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

    ... into Trust in 1990 The Tribe has been leasing to a long-term tenant whose lease will end in July 2010 Wundar Hall Project Wundar Hall is a 34,000 sq ft dormitory building ...

  17. TBB-0042- In the Matter of Curtis Hall

    Broader source: Energy.gov [DOE]

    This letter concerns the complaint of retaliation filed by Curtis Hall (the complainant or Mr. Hall) with the Department of Energy under 10 C . F. R. Part 7 0 8 , the DOE Con tractor Employee ...

  18. Phase transitions in quantum Hall multiple layer systems

    SciTech Connect (OSTI)

    Pusep, Yu A.; Fernandes dos Santos, L.; Smirnov, D.; Bakarov, A. K.; Toropov, A. I.

    2013-12-04

    Polarized photoluminescence from multiple well electron systems was studied in the regime of the integer quantum Hall effect. Two quantum Hall ferromagnetic ground states assigned to the uncorrelated miniband quantum Hall state and to the spontaneous interwell phase coherent dimer quantum Hall state were observed. The photoluminescence associated with these states exhibits features caused by finite-size skyrmions. The depolarization of the ferromagnetic ground state was observed in bilayer system.

  19. Effective Field Theory of Fractional Quantized Hall Nematics (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect Effective Field Theory of Fractional Quantized Hall Nematics Citation Details In-Document Search Title: Effective Field Theory of Fractional Quantized Hall Nematics We present a Landau-Ginzburg theory for a fractional quantized Hall nematic state and the transition to it from an isotropic fractional quantum Hall state. This justifies Lifshitz-Chern-Simons theory - which is shown to be its dual - on a more microscopic basis and enables us to compute a ground state

  20. Spring 2015 Henderson Hall Education and Career Fair

    Office of Energy Efficiency and Renewable Energy (EERE)

    Location: Smith Gym, Henderson Hall, Arlington, VAPOC: DOECorporateRecruitment@hq.doe.govWebsite: http://bit.ly/1FRIJOF

  1. Parametric Investigations of Non-Conventional Hall Thruster

    SciTech Connect (OSTI)

    Raitses, Y.; Fisch, N.J.

    2001-01-12

    Hall thrusters might better scale to low power with non-conventional geometry. A 9 cm cylindrical, ceramic-channel, Hall thruster with a cusp-type magnetic field distribution has been investigated. It exhibits discharge characteristics similar to conventional coaxial Hall thrusters, but does not expose as much channel surface. Significantly, its operation is not accompanied by large amplitude discharge low frequency oscillations.

  2. Newmark-Hall synthetic history development

    SciTech Connect (OSTI)

    Aramayo, G.A.

    1990-11-01

    The methodology used to develop synthetic acceleration time histories with spectral content that envelopes the Newmark-Hall spectra is described. Six acceleration time histories are developed for two conditions of foundation and 3 critical damping factors. The target spectra corresponds to the mediam centered probability level.

  3. Moderate positive spin Hall angle in uranium

    SciTech Connect (OSTI)

    Singh, Simranjeet; Anguera, Marta; Barco, Enrique del E-mail: cwmsch@rit.edu; Springell, Ross; Miller, Casey W. E-mail: cwmsch@rit.edu

    2015-12-07

    We report measurements of spin pumping and the inverse spin Hall effect in Ni{sub 80}Fe{sub 20}/uranium bilayers designed to study the efficiency of spin-charge interconversion in a super-heavy element. We employ broad-band ferromagnetic resonance on extended films to inject a spin current from the Ni{sub 80}Fe{sub 20} (permalloy) into the uranium layer, which is then converted into an electric field by the inverse spin Hall effect. Surprisingly, our results suggest a spin mixing conductance of order 2 × 10{sup 19} m{sup −2} and a positive spin Hall angle of 0.004, which are both merely comparable with those of several transition metals. These results thus support the idea that the electronic configuration may be at least as important as the atomic number in governing spin pumping across interfaces and subsequent spin Hall effects. In fact, given that both the magnitude and the sign are unexpected based on trends in d-electron systems, materials with unfilled f-electron orbitals may hold additional exploration avenues for spin physics.

  4. Comparison of Secondary Islands in Collisional Reconnection to Hall Reconnection

    SciTech Connect (OSTI)

    Shepherd, L. S.; Cassak, P. A.

    2010-07-02

    Large-scale resistive Hall-magnetohydrodynamic simulations of the transition from Sweet-Parker (collisional) to Hall (collisionless) magnetic reconnection are presented; the first to separate secondary islands from collisionless effects. Three main results are described. There exists a regime with secondary islands but without collisionless effects, and the reconnection rate is faster than Sweet-Parker, but significantly slower than Hall reconnection. This implies that secondary islands do not cause the fastest reconnection rates. The onset of Hall reconnection ejects secondary islands from the vicinity of the X line, implying that energy is released more rapidly during Hall reconnection. Coronal applications are discussed.

  5. Fast Camera Imaging of Hall Thruster Ignition

    SciTech Connect (OSTI)

    C.L. Ellison, Y. Raitses and N.J. Fisch

    2011-02-24

    Hall thrusters provide efficient space propulsion by electrostatic acceleration of ions. Rotating electron clouds in the thruster overcome the space charge limitations of other methods. Images of the thruster startup, taken with a fast camera, reveal a bright ionization period which settles into steady state operation over 50 μs. The cathode introduces azimuthal asymmetry, which persists for about 30 μs into the ignition. Plasma thrusters are used on satellites for repositioning, orbit correction and drag compensation. The advantage of plasma thrusters over conventional chemical thrusters is that the exhaust energies are not limited by chemical energy to about an electron volt. For xenon Hall thrusters, the ion exhaust velocity can be 15-20 km/s, compared to 5 km/s for a typical chemical thruster

  6. The Honorable,Edward Rendell, '. City Hall

    Office of Legacy Management (LM)

    I:! i394 .\ . The Honorable,Edward Rendell, '. City Hall Philadelphia, Pennsylvania 19107 Dear Mayor Rendell : ', ,' . , Secretary of Energy Hazel O',teary has announced-a new approach.to.openness in the Department of Energy (DDE) and its communications with the public. . In support of this initiative, we are.pleased to forward the enclosed information related to the,former. Penn Salt Manufacturing' Co. site in your jurisdiction that performed.work for DOE or its predecessor agencies. This

  7. Centre Hall, Pennsylvania: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hall, Pennsylvania: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 40.8475635, -77.6861093 Show Map Loading map... "minzoom":false,"mappingser...

  8. 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...

  9. Hall's Warehouse Corp Solar Project | Open Energy Information

    Open Energy Info (EERE)

    Corp. Solar Project" Retrieved from "http:en.openei.orgwindex.php?titleHall%27sWarehouseCorpSolarProject&oldid397541" Feedback Contact needs updating Image...

  10. Building America Top Innovations Hall of Fame Profile … High...

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

    ... TOP INNOVATIONS BUILDING AMERICA BUILDING AMERICA TOP INNOVATIONS HALL OF FAME PROFILE Habitat affiliates across the country held "blitz builds" to construct homes for Gulf Coast ...

  11. Lecture & Dining Halls - Combustion Energy Frontier Research Center

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

    Lecture & Dining Halls Lecture & Dining Halls Lecture Halls: Friend Center SeeSchedule of Events for schedule and location of lectures. How far are the lecture halls from the dormitories? Friend Center is a quick 10 minute walk from the Butler dormitories. See campus map for walking directions. There is also a free campus shuttle that will take you from outside the Icahn Lab on Washington Road to the Friend Center. See http://www.princeton.edu/transportation/ttroutes/ for shuttle times.

  12. Robert B. Laughlin and the Fractional Quantum Hall Effect

    Office of Scientific and Technical Information (OSTI)

    In 1983, Laughlin, then at the Lawrence Livermore National Laboratory, provided the ... quantum Hall effect.'1 ' "My presence at Livermore was crucial to my work," says Laughlin. ...

  13. Rebuilding It Better: Greensburg, Kansas. City Hall (Brochure)

    Broader source: Energy.gov [DOE]

    This brochure details the energy efficient and sustainable aspects of the LEED Platinum-designated City Hall building in Greensburg, Kansas.

  14. Charge carrier coherence and Hall effect in organic semiconductors

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

    Yi, H. T.; Gartstein, Y. N.; Podzorov, V.

    2016-03-30

    Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force actingmore » on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Lastly, our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor.« less

  15. Robert B. Laughlin and the Fractional Quantum Hall Effect

    Office of Scientific and Technical Information (OSTI)

    Robert B. Laughlin and the Fractional Quantum Hall Effect Resources with Additional Information Robert B. Laughlin Photo Courtesy of LLNL Robert B. Laughlin shared the 1998 Nobel...

  16. Rebuilding It Better: Greensburg, Kansas. City Hall (Brochure)

    SciTech Connect (OSTI)

    Not Available

    2010-04-01

    This document showcases the LEED-Platinum designed Greensburg City Hall, which was rebuilt green, after a massive tornado destroyed Greensburg, Kansas in May 2007.

  17. Building America Top Innovations Hall of Fame Profile - Building...

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

    Building America Top Innovations Hall of Fame Profile - Building America's Top Innovations Propel the Home Building Industry toward Higher Performance Building America Top ...

  18. Systems and Methods for Cylindrical Hall Thrusters with Independently...

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

    Systems and Methods for Cylindrical Hall Thrusters with Independently Controllable Ionization and Acceleration Stages Yevgeny Raitses, Nathaniel J. Fisch and Kevin D. Diamant (The...

  19. Anomalous spin precession and spin Hall effect in semiconductor...

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Search Results Journal Article: Anomalous spin precession and spin Hall effect in semiconductor quantum wells Citation Details In-Document Search Title: Anomalous ...

  20. Rebuilding It Better: Greensburg, Kansas, City Hall (Brochure)

    SciTech Connect (OSTI)

    Not Available

    2010-09-01

    This brochure details the energy efficient and sustainable aspects of the LEED Platinum-designated City Hall building in Greensburg, Kansas.

  1. User-Program_Town_Hall-11.pptx

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

    representative on the UEC. Nominations were accepted from the floor as follows: * Rafael Verduzco nominated by Marco Nardelli for at---large member, and seconded b y M artyn M...

  2. National Energy Literacy Virtual Town Hall

    Broader source: Energy.gov [DOE]

    The webinar will be a dynamic, virtual conversation for educators about ongoing efforts from across the country in utilizing the Department of Energy's Energy Literacy Framework to address one of our nation's’ biggest national challenges, energy illiteracy.

  3. Town Hall Meeting | OpenEI Community

    Open Energy Info (EERE)

    introductions - name, company, potential icebreaker (what's your favorite analysis tool, programming language, energy sector..) 5 minutes OpenEI: what's new and coming soon 5...

  4. NUG_TownHall_Oct2009.ppt

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

    (memory, IO, CPU hours) * How easy is it for you to translate your science and research objectives into quantitative computational requirements? - Which is the hardest...

  5. Synchronization of spin-transfer torque oscillators by spin pumping, inverse spin Hall, and spin Hall effects

    SciTech Connect (OSTI)

    Elyasi, Mehrdad; Bhatia, Charanjit S.; Yang, Hyunsoo

    2015-02-14

    We have proposed a method to synchronize multiple spin-transfer torque oscillators based on spin pumping, inverse spin Hall, and spin Hall effects. The proposed oscillator system consists of a series of nano-magnets in junction with a normal metal with high spin-orbit coupling, and an accumulative feedback loop. We conduct simulations to demonstrate the effect of modulated charge currents in the normal metal due to spin pumping from each nano-magnet. We show that the interplay between the spin Hall effect and inverse spin Hall effect results in synchronization of the nano-magnets.

  6. Lees-Kubota Lecture Hall, Guggenheim 101

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

    SPECIAL SEMINAR - Monday, November 3 rd Lees-Kubota Lecture Hall, Guggenheim 101 11:15am-12:15pm "Perovskite Solar Cells: Towards New Materials and New Applications" Professor Nripan Mathews Nanyang Technological University, Singapore Abstract: Perovskite solar cells have attracted a lot of attention primarily due to its high efficiency (~19%). Much of the attention has focused on CH 3 NH 3 PbI 3 (Eg-1.55eV) whose high performance can be traced to a high absorption coefficient as well

  7. Segmented electrode hall thruster with reduced plume

    DOE Patents [OSTI]

    Fisch, Nathaniel J.; Raitses, Yevgeny

    2004-08-17

    An apparatus and method for thrusting plasma, utilizing a Hall thruster with segmented electrodes along the channel, which make the acceleration region as localized as possible. Also disclosed are methods of arranging the electrodes so as to minimize erosion and arcing. Also disclosed are methods of arranging the electrodes so as to produce a substantial reduction in plume divergence. The use of electrodes made of emissive material will reduce the radial potential drop within the channel, further decreasing the plume divergence. Also disclosed is a method of arranging and powering these electrodes so as to provide variable mode operation.

  8. Halls Middle School students get a taste of science at Y-12 ...

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

    Halls Middle School ... Halls Middle School students get a taste of science at Y-12 Posted: May 21, 2013 - 12:40pm Engineering, science and history experts give Halls Middle School...

  9. Undulator Hall Air Temperature Fault Scenarios

    SciTech Connect (OSTI)

    Sevilla, J.; Welch, J.; ,

    2010-11-17

    Recent experience indicates that the LCLS undulator segments must not, at any time following tuning, be allowed to change temperature by more than about {+-}2.5 C or the magnetic center will irreversibly shift outside of acceptable tolerances. This vulnerability raises a concern that under fault conditions the ambient temperature in the Undulator Hall might go outside of the safe range and potentially could require removal and retuning of all the segments. In this note we estimate changes that can be expected in the Undulator Hall air temperature for three fault scenarios: (1) System-wide power failure; (2) Heating Ventilation and Air Conditioning (HVAC) system shutdown; and (3) HVAC system temperature regulation fault. We find that for either a system-wide power failure or an HVAC system shutdown (with the technical equipment left on), the short-term temperature changes of the air would be modest due to the ability of the walls and floor to act as a heat ballast. No action would be needed to protect the undulator system in the event of a system-wide power failure. Some action to adjust the heat balance, in the case of the HVAC power failure with the equipment left on, might be desirable but is not required. On the other hand, a temperature regulation failure of the HVAC system can quickly cause large excursions in air temperature and prompt action would be required to avoid damage to the undulator system.

  10. Cylindrical Hall Thrusters with Permanent Magnets

    SciTech Connect (OSTI)

    Raitses, Yevgeny; Merino, Enrique; Fisch, Nathaniel J.

    2010-10-18

    The use of permanent magnets instead of electromagnet coils for low power Hall thrusters can offer a significant reduction of both the total electric power consumption and the thruster mass. Two permanent magnet versions of the miniaturized cylindrical Hall thruster (CHT) of different overall dimensions were operated in the power range of 50W-300 W. The discharge and plasma plume measurements revealed that the CHT thrusters with permanent magnets and electromagnet coils operate rather differently. In particular, the angular ion current density distribution from the permanent magnet thrusters has an unusual halo shape, with a majority of high energy ions flowing at large angles with respect to the thruster centerline. Differences in the magnetic field topology outside the thruster channel and in the vicinity of the channel exit are likely responsible for the differences in the plume characteristics measured for the CHTs with electromagnets and permanent magnets. It is shown that the presence of the reversing-direction or cusp-type magnetic field configuration inside the thruster channel without a strong axial magnetic field outside the thruster channel does not lead to the halo plasma plume from the CHT. __________________________________________________

  11. Pair spectrometer hodoscope for Hall D at Jefferson Lab

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

    Barbosa, Fernando J.; Hutton, Charles L.; Sitnikov, Alexandre; Somov, Alexander S.; Somov, S.; Tolstukhin, Ivan

    2015-09-21

    We present the design of the pair spectrometer hodoscope fabricated at Jefferson Lab and installed in the experimental Hall D. The hodoscope consists of thin scintillator tiles; the light from each tile is collected using wave-length shifting fibers and detected using a Hamamatsu silicon photomultiplier. Light collection was measured using relativistic electrons produced in the tagger area of the experimental Hall B.

  12. Energy spectrum, dissipation, and spatial structures in reduced Hall magnetohydrodynamic

    SciTech Connect (OSTI)

    Martin, L. N.; Dmitruk, P.; Gomez, D. O.

    2012-05-15

    We analyze the effect of the Hall term in the magnetohydrodynamic turbulence under a strong externally supported magnetic field, seeing how this changes the energy cascade, the characteristic scales of the flow, and the dynamics of global magnitudes, with particular interest in the dissipation. Numerical simulations of freely evolving three-dimensional reduced magnetohydrodynamics are performed, for different values of the Hall parameter (the ratio of the ion skin depth to the macroscopic scale of the turbulence) controlling the impact of the Hall term. The Hall effect modifies the transfer of energy across scales, slowing down the transfer of energy from the large scales up to the Hall scale (ion skin depth) and carrying faster the energy from the Hall scale to smaller scales. The final outcome is an effective shift of the dissipation scale to larger scales but also a development of smaller scales. Current sheets (fundamental structures for energy dissipation) are affected in two ways by increasing the Hall effect, with a widening but at the same time generating an internal structure within them. In the case where the Hall term is sufficiently intense, the current sheet is fully delocalized. The effect appears to reduce impulsive effects in the flow, making it less intermittent.

  13. Fractional Quantum Hall Effect at Landau Level Filling v=4/11...

    Office of Scientific and Technical Information (OSTI)

    Fractional Quantum Hall Effect at Landau Level Filling v411. Citation Details In-Document Search Title: Fractional Quantum Hall Effect at Landau Level Filling v411. Abstract...

  14. Non-abelian fractional quantum hall effect for fault-resistant...

    Office of Scientific and Technical Information (OSTI)

    Non-abelian fractional quantum hall effect for fault-resistant topological quantum computation. Citation Details In-Document Search Title: Non-abelian fractional quantum hall...

  15. WIPP Employee Inducted Into Mine Rescue Hall of Fame - WIPP Teams...

    Office of Environmental Management (EM)

    Employee Inducted Into Mine Rescue Hall of Fame - WIPP Teams Recognized at National Competition WIPP Employee Inducted Into Mine Rescue Hall of Fame - WIPP Teams Recognized at ...

  16. Anomalous Hall effect in YIG|Pt bilayers

    SciTech Connect (OSTI)

    Meyer, Sibylle Schlitz, Richard; Geprägs, Stephan; Opel, Matthias; Huebl, Hans; Goennenwein, Sebastian T. B.; Gross, Rudolf

    2015-03-30

    We measure the ordinary and the anomalous Hall effect in a set of yttrium iron garnet|platinum (YIG|Pt) bilayers via magnetization orientation dependent magnetoresistance experiments. Our data show that the presence of the ferrimagnetic insulator YIG leads to an anomalous Hall effect like voltage in Pt, which is sensitive to both Pt thickness and temperature. Interpretation of the experimental findings in terms of the spin Hall anomalous Hall effect indicates that the imaginary part of the spin mixing conductance G{sub i} plays a crucial role in YIG|Pt bilayers. In particular, our data suggest a sign change in G{sub i} between 10 K and 300 K. Additionally, we report a higher order Hall effect contribution, which appears in thin Pt films on YIG at low temperatures.

  17. Small Town Using Wind Power to Offset Electricity Costs

    Broader source: Energy.gov [DOE]

    Wind turbines will be used to supply electricity for the town hall, maintenance building, library and help power the town's water system.

  18. Spin Hall magnetoresistance at high temperatures

    SciTech Connect (OSTI)

    Uchida, Ken-ichi; Qiu, Zhiyong; Kikkawa, Takashi; Iguchi, Ryo; Saitoh, Eiji

    2015-02-02

    The temperature dependence of spin Hall magnetoresistance (SMR) in Pt/Y{sub 3}Fe{sub 5}O{sub 12} (YIG) bilayer films has been investigated in a high temperature range from room temperature to near the Curie temperature of YIG. The experimental results show that the magnitude of the magnetoresistance ratio induced by the SMR monotonically decreases with increasing the temperature and almost disappears near the Curie temperature. We found that, near the Curie temperature, the temperature dependence of the SMR in the Pt/YIG film is steeper than that of a magnetization curve of the YIG; the critical exponent of the magnetoresistance ratio is estimated to be 0.9. This critical behavior of the SMR is attributed mainly to the temperature dependence of the spin-mixing conductance at the Pt/YIG interface.

  19. Stacking order dependence of inverse spin Hall effect and anomalous Hall effect in spin pumping experiments

    SciTech Connect (OSTI)

    Kim, Sang-Il; Seo, Min-Su; Park, Seung-Young; Kim, Dong-Jun; Park, Byong-Guk

    2015-05-07

    The dependence of the measured DC voltage on the non-magnetic material (NM) in NM/CoFeB and CoFeB/NM bilayers is studied under ferromagnetic resonance conditions in a TE{sub 011} resonant cavity. The directional change of the inverse spin Hall effect (ISHE) voltage V{sub ISHE} for the stacking order of the bilayer can separate the pure V{sub ISHE} and the anomalous Hall effect (AHE) voltage V{sub AHE} utilizing the method of addition and subtraction. The Ta and Ti NMs show a broad deviation of the spin Hall angle θ{sub ISH}, which originates from the AHE in accordance with the high resistivity of NMs. However, the Pt and Pd NMs show that the kinds of NMs with low resistivity are consistent with the previously reported θ{sub ISH} values. Therefore, the characteristics that NM should simultaneously satisfy to obtain a reasonable V{sub ISHE} value in bilayer systems are large θ{sub ISH} and low resistivity.

  20. Parametric Investigations of Miniaturized Cylindrical and Annular Hall Thrusters

    SciTech Connect (OSTI)

    A. Smirnov; Y. Raitses; N.J. Fisch

    2001-10-16

    A cylindrical geometry Hall thruster may overcome certain physical and technological limitations in scaling down of Hall thrusters to miniature sizes. The absence of the inner wall and use of the cusp magnetic field can potentially reduce heating of the thruster parts and erosion of the channel. A 2.6 cm miniaturized Hall thruster of a flexible design was built and successfully operated in the power range of 50-300 W. Comparison of preliminary results obtained for cylindrical and annular thruster configurations is presented.

  1. Notify Work Coordinators Before Working in/Entering Halls | Jefferson Lab

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

    Notify Work Coordinators Before Working in/Entering Halls Remember to Notify Work Coordinators Before Working in/Entering Hall A, B, C & D The Worker Safety Committee reminds all members of the Jefferson Lab community that they must notify the appropriate experimental hall Work Coordinator (WC) - for Hall A, B, C or D - in advance of doing any work in that hall or in advance of taking any materials or equipment into or out of that hall. Hall Work Coordinators ask to be notified by phone call

  2. Hall County, Nebraska: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Hide Map This article is a stub. You can help OpenEI by expanding it. Hall County is a county in Nebraska. Its FIPS County Code is 079. It is classified as ASHRAE...

  3. Building America Top Innovations Hall of Fame Profile … EEBA...

    Energy Savers [EERE]

    ... TOP INNOVATIONS BUILDING AMERICA BUILDING AMERICA TOP INNOVATIONS HALL OF FAME PROFILE The ... Drain all water away from the structure The secret to water management is to construct the ...

  4. Charge carrier coherence and Hall effect in organic semiconductors

    Office of Scientific and Technical Information (OSTI)

    OPEN: Charge carrier coherence and Hall effect in organic semiconductors H. T. Yi1, Y. N. Gartstein2 & V. Podzorov1-3 Received: 21 January 2016 Accepted: 29 February 2016 ...

  5. Property:Building/FloorAreaTheatresConcertHallsCinemas | Open...

    Open Energy Info (EERE)

    Property Edit with form History Property:BuildingFloorAreaTheatresConcertHallsCinemas Jump to: navigation, search This is a property of type Number. Floor area for Theatres,...

  6. Building America Top Innovations Hall of Fame Profile - Building

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

    America's Top Innovations Propel the Home Building Industry toward Higher Performance | Department of Energy Building America Top Innovations Hall of Fame Profile - Building America's Top Innovations Propel the Home Building Industry toward Higher Performance Building America Top Innovations Hall of Fame Profile - Building America's Top Innovations Propel the Home Building Industry toward Higher Performance This Building America Innovations profile describes the concept for the U.S.

  7. Hall effect measurements on InAs nanowires

    SciTech Connect (OSTI)

    Bloemers, Ch.; Grap, T.; Lepsa, M. I.; Moers, J.; Gruetzmacher, D.; Lueth, H.; Trellenkamp, St.; Schaepers, Th.

    2012-10-08

    We have processed Hall contacts on InAs nanowires grown by molecular beam epitaxy using an electron beam lithography process with an extremely high alignment accuracy. The carrier concentrations determined from the Hall effect measurements on these nanowires are lower by a factor of about 4 in comparison with those measured by the common field-effect technique. The results are used to evaluate quantitatively the charging effect of the interface and surface states.

  8. Exact solutions of the incompressible dissipative Hall magnetohydrodynamics

    SciTech Connect (OSTI)

    Xia, Zhenwei; Yang, Weihong

    2015-03-15

    By using analytical method, the exact solutions of the incompressible dissipative Hall magnetohydrodynamics (MHD) equations are derived. It is found that a phase difference may occur between the velocity and magnetic field fluctuations when the kinetic and magnetic Reynolds numbers are both very large. Since velocity and magnetic field fluctuations are both circular polarized, the phase difference makes them no longer parallel or anti-parallel like that in the incompressible ideal Hall MHD.

  9. Magnetometry of micro-magnets with electrostatically defined Hall bars

    SciTech Connect (OSTI)

    Lachance-Quirion, Dany; Camirand Lemyre, Julien; Bergeron, Laurent; Sarra-Bournet, Christian; Pioro-Ladrière, Michel

    2015-11-30

    Micro-magnets are key components for quantum information processing with individual spins, enabling arbitrary rotations and addressability. In this work, characterization of sub-micrometer sized CoFe ferromagnets is performed with Hall bars electrostatically defined in a two-dimensional electron gas. Due to the ballistic nature of electron transport in the cross junction of the Hall bar, anomalies such as the quenched Hall effect appear near zero external magnetic field, thus hindering the sensitivity of the magnetometer to small magnetic fields. However, it is shown that the sensitivity of the diffusive limit can be almost completely restored at low temperatures using a large current density in the Hall bar of about 10 A/m. Overcoming the size limitation of conventional etched Hall bars with electrostatic gating enables the measurement of magnetization curves of 440 nm wide micro-magnets with a signal-to-noise ratio above 10{sup 3}. Furthermore, the inhomogeneity of the stray magnetic field created by the micro-magnets is directly measured using the gate-voltage-dependent width of the sensitive area of the Hall bar.

  10. Stability of Hall equilibria in neutron star crusts

    SciTech Connect (OSTI)

    Marchant, Pablo; Reisenegger, Andreas; Valdivia, Juan Alejandro; Hoyos, Jaime H.

    2014-12-01

    In the solid crusts of neutron stars, the advection of the magnetic field by the current-carrying electrons, an effect known as Hall drift, should play a very important role as the ions remain essentially fixed (as long as the solid does not break). Although Hall drift preserves the magnetic field energy, it has been argued that it may drive a turbulent cascade to scales at which ohmic dissipation becomes effective, allowing a much faster decay in objects with very strong fields. On the other hand, it has been found that there are 'Hall equilibria', i.e., field configurations that are unaffected by Hall drift. Here we address the crucial question of the stability of these equilibria through axially symmetric (two-dimensional (2D)) numerical simulations of Hall drift and ohmic diffusion, with the simplifying assumption of uniform electron density and conductivity. We demonstrate the 2D stability of a purely poloidal equilibrium, for which ohmic dissipation makes the field evolve toward an attractor state through adjacent stable configurations, around which damped oscillations occur. For this field, the decay scales with the ohmic timescale. We also study the case of an unstable equilibrium consisting of both poloidal and toroidal field components that are confined within the crust. This field evolves into a stable configuration, which undergoes damped oscillations superimposed on a slow evolution toward an attractor, just as the purely poloidal one.

  11. Optical detection of spin Hall effect in metals

    SciTech Connect (OSTI)

    Erve, O. M. J. van ‘t Hanbicki, A. T.; McCreary, K. M.; Li, C. H.; Jonker, B. T.

    2014-04-28

    Optical techniques have been widely used to probe the spin Hall effect in semiconductors. In metals, however, only electrical methods such as nonlocal spin valve transport, ferromagnetic resonance, or spin torque transfer experiments have been successful. These methods require complex processing techniques and measuring setups. We show here that the spin Hall effect can be observed in non-magnetic metals such as Pt and β-W, using a standard bench top magneto-optical Kerr system with very little sample preparation. Applying a square wave current and using Fourier analysis significantly improve our detection level. One can readily determine the angular dependence of the induced polarization on the bias current direction (very difficult to do with voltage detection), the orientation of the spin Hall induced polarization, and the sign of the spin Hall angle. This optical approach is free from the complications of various resistive effects, which can compromise voltage measurements. This opens up the study of spin Hall effect in metals to a variety of spin dynamic and spatial imaging experiments.

  12. Reconnection dynamics with secondary tearing instability in compressible Hall plasmas

    SciTech Connect (OSTI)

    Ma, Z. W. Wang, L. C.; Li, L. J.

    2015-06-15

    The dynamics of a secondary tearing instability is systematically investigated based on compressible Hall magnetohydrodynamic. It is found that in the early nonlinear phase of magnetic reconnection before onset of the secondary tearing instability, the geometry of the magnetic field in the reconnection region tends to form a Y-type structure in a weak Hall regime, instead of an X-type structure in a strong Hall regime. A new scaling law is found that the maximum reconnection rate in the early nonlinear stage is proportional to the square of the ion inertial length (γ∝d{sub i}{sup 2}) in the weak Hall regime. In the late nonlinear phase, the thin elongated current sheet associated with the Y-type geometry of the magnetic field breaks up to form a magnetic island due to a secondary tearing instability. After the onset of the secondary tearing mode, the reconnection rate is substantially boosted by the formation of the X-type geometries of magnetic field in the reconnection regions. With a strong Hall effect, the maximum reconnection rate linearly increases with the increase of the ion inertial length (γ∝d{sub i})

  13. Study of the effects of guide field on Hall reconnection

    SciTech Connect (OSTI)

    Tharp, T. D.; Yamada, M.; Ji, H.; Lawrence, E.; Dorfman, S.; Myers, C.; Yoo, J.; Huang, Y.-M.; Bhattacharjee, A.

    2013-05-15

    The results from guide field studies on the Magnetic Reconnection Experiment (MRX) are compared with results from Hall magnetohydrodynamic (HMHD) reconnection simulation with guide field. The quadrupole field, a signature of two-fluid reconnection at zero guide field, is modified by the presence of a finite guide field in a manner consistent with HMHD simulation. The modified Hall current profile contains reduced electron flows in the reconnection plane, which quantitatively explains the observed reduction of the reconnection rate. The present results are consistent with the hypothesis that the local reconnection dynamics is dominated by Hall effects in the collisionless regime of the MRX plasmas. While very good agreement is seen between experiment and simulations, we note that an important global feature of the experiments, a compression of the guide field by the reconnecting plasma, is not represented in the simulations.

  14. On the question of hysteresis in Hall magnetohydrodynamic reconnection

    SciTech Connect (OSTI)

    Sullivan, Brian P.; Bhattacharjee, A.; Huang Yimin

    2010-11-15

    Controversy has been raised regarding the cause of hysteresis, or bistability, of solutions to the equations that govern the geometry of the reconnection region in Hall magnetohydrodynamic (MHD) systems. This brief communication presents a comparison of the frameworks within which this controversy has arisen and illustrates that the Hall MHD hysteresis originally discovered numerically by Cassak et al. [Phys. Rev. Lett. 95, 235002 (2005)] is a different phenomenon from that recently reported by Zocco et al. [Phys. Plasmas 16, 110703 (2009)] on the basis of analysis and simulations in electron MHD with finite electron inertia. We demonstrate that the analytic prediction of hysteresis in EMHD does not describe or explain the hysteresis originally reported in Hall MHD, which is shown to persist even in the absence of electron inertia.

  15. Reconnection events in two-dimensional Hall magnetohydrodynamic turbulence

    SciTech Connect (OSTI)

    Donato, S.; Servidio, S.; Carbone, V. [Dipartimento di Fisica, Universita della Calabria, I-87036 Cosenza (Italy); Dmitruk, P. [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and Instituto de Fisica de Buenos Aires, CONICET, Buenos Aires (Argentina); Shay, M. A.; Matthaeus, W. H. [Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716 (United States); Cassak, P. A. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States)

    2012-09-15

    The statistical study of magnetic reconnection events in two-dimensional turbulence has been performed by comparing numerical simulations of magnetohydrodynamics (MHD) and Hall magnetohydrodynamics (HMHD). The analysis reveals that the Hall term plays an important role in turbulence, in which magnetic islands simultaneously reconnect in a complex way. In particular, an increase of the Hall parameter, the ratio of ion skin depth to system size, broadens the distribution of reconnection rates relative to the MHD case. Moreover, in HMHD the local geometry of the reconnection region changes, manifesting bifurcated current sheets and quadrupolar magnetic field structures in analogy to laminar studies, leading locally to faster reconnection processes in this case of reconnection embedded in turbulence. This study supports the idea that the global rate of energy dissipation is controlled by the large scale turbulence, but suggests that the distribution of the reconnection rates within the turbulent system is sensitive to the microphysics at the reconnection sites.

  16. Admittance of multiterminal quantum Hall conductors at kilohertz frequencies

    SciTech Connect (OSTI)

    Hernndez, C.; Consejo, C.; Chaubet, C.; Degiovanni, P.

    2014-03-28

    We present an experimental study of the low frequency admittance of quantum Hall conductors in the [100?Hz, 1?MHz] frequency range. We show that the frequency dependence of the admittance of the sample strongly depends on the topology of the contacts connections. Our experimental results are well explained within the Christen and Bttiker approach for finite frequency transport in quantum Hall edge channels taking into account the influence of the coaxial cables capacitance. In the Hall bar geometry, we demonstrate that there exists a configuration in which the cable capacitance does not influence the admittance measurement of the sample. In this case, we measure the electrochemical capacitance of the sample and observe its dependence on the filling factor.

  17. Hall effect in a strong magnetic field: Direct comparisons of compressible magnetohydrodynamics and the reduced Hall magnetohydrodynamic equations

    SciTech Connect (OSTI)

    Martin, L. N.; Dmitruk, P.; Gomez, D. O.

    2010-11-15

    In this work we numerically test a model of Hall magnetohydrodynamics in the presence of a strong mean magnetic field: the reduced Hall magnetohydrodynamic model (RHMHD) derived by [Gomez et al., Phys. Plasmas 15, 102303 (2008)] with the addition of weak compressible effects. The main advantage of this model lies in the reduction of computational cost. Nevertheless, up until now the degree of agreement with the original Hall MHD system and the range of validity in a regime of turbulence were not established. In this work direct numerical simulations of three-dimensional Hall MHD turbulence in the presence of a strong mean magnetic field are compared with simulations of the weak compressible RHMHD model. The results show that the degree of agreement is very high (when the different assumptions of RHMHD, such as spectral anisotropy, are satisfied). Nevertheless, when the initial conditions are isotropic but the mean magnetic field is maintained strong, the results differ at the beginning but asymptotically reach a good agreement at relatively short times. We also found evidence that the compressibility still plays a role in the dynamics of these systems, and the weak compressible RHMHD model is able to capture these effects. In conclusion the weak compressible RHMHD model is a valid approximation of the Hall MHD turbulence in the relevant physical context.

  18. Quantum anomalous Hall effect in topological insulator memory

    SciTech Connect (OSTI)

    Jalil, Mansoor B. A.; Tan, S. G.; Siu, Z. B.

    2015-05-07

    We theoretically investigate the quantum anomalous Hall effect (QAHE) in a magnetically coupled three-dimensional-topological insulator (3D-TI) system. We apply the generalized spin-orbit coupling Hamiltonian to obtain the Hall conductivity σ{sup xy} of the system. The underlying topology of the QAHE phenomenon is then analyzed to show the quantization of σ{sup xy} and its relation to the Berry phase of the system. Finally, we analyze the feasibility of utilizing σ{sup xy} as a memory read-out in a 3D-TI based memory at finite temperatures, with comparison to known magnetically doped 3D-TIs.

  19. Nanoconstriction-based spin-Hall nano-oscillator

    SciTech Connect (OSTI)

    Demidov, V. E.; Urazhdin, S.; Zholud, A.; Sadovnikov, A. V.; Demokritov, S. O.

    2014-10-27

    We experimentally demonstrate magnetic nano-oscillators driven by pure spin current produced by the spin Hall effect in a bow tie-shaped nanoconstriction. These devices exhibit single-mode auto-oscillation and generate highly-coherent electronic microwave signals with a significant power and the spectral linewidth as low as 6.2 MHz at room temperature. The proposed simple and flexible device geometry is amenable to straightforward implementation of advanced spintronic structures such as chains of mutually coupled spin-Hall nano-oscillators.

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

    SciTech Connect (OSTI)

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

    2015-06-01

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

  1. VEE-0067- In the Matter of M.L. Halle Oil Service, Inc.

    Broader source: Energy.gov [DOE]

    On August 9, 1999 M.L. Halle Oil Service, Inc. (Halle) of Manchester, New Hampshire, filed an Application for Exception with the Office of Hearings and Appeals (OHA) of the Department of Energy ...

  2. Quantum anomalous Hall effect in single-layer and bilayer graphene...

    Office of Scientific and Technical Information (OSTI)

    Quantum anomalous Hall effect in single-layer and bilayer graphene Citation Details In-Document Search Title: Quantum anomalous Hall effect in single-layer and bilayer graphene ...

  3. Bernhard Mecking steps down as Hall B leader at Jefferson Lab | Jefferson

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

    Lab Bernhard Mecking steps down as Hall B leader at Jefferson Lab Bernhard Mecking Jefferson Lab staff scientist Bernhard Mecking with the CEBAF Large Acceptance Spectrometer (CLAS) in Hall B. Bernhard Mecking steps down as Hall B leader at Jefferson Lab April 2, 2003 On 1 February 2003, Bernhard Mecking stepped down as leader of Hall B to return to full-time research at the Department of Energy's Thomas Jefferson National Accelerator Facility (Jefferson Lab) in Newport News, Virginia.

  4. Measurements of Plasma Potential Distribution in Segmented Electrode Hall Thruster

    SciTech Connect (OSTI)

    Y. Raitses; D. Staack; N.J. Fisch

    2001-10-16

    Use of a segmented electrode placed at the Hall thruster exit can substantially reduce the voltage potential drop in the fringing magnetic field outside the thruster channel. In this paper, we investigate the dependence of this effect on thruster operating conditions and segmented electrode configuration. A fast movable emissive probe is used to measure plasma potential in a 1 kW laboratory Hall thruster with semented electrodes made of a graphite material. Relatively small probe-induced perturbations of the thruster discharge in the vicinity of the thruster exit allow a reasonable comparison of the measured results for different thruster configurations. It is shown that the plasma potential distribution is almost not sensitive to changes of the electrode potential, but depends on the magnetic field distribution and the electrode placement.

  5. Recent Results of TMD Measurements from Jefferson Lab Hall A

    SciTech Connect (OSTI)

    Jiang, Xiaodong

    2013-10-01

    This slide-show presents results on transverse momentum distributions. The presentation covers: target single-spin asymmetry (SSA) (in parity conserving interactions); Results of JLab Hall A polarized {sup 3}He target TMD measurement; Semi-?inclusive deep-inelastic scattering channels (E06-010); Target single-spin asymmetry A{sub UT}, Collins and Sivers SSA on neutron; Double-spin asymmetry A{sub LT}, extract TMD g{sub 1T} on neutron; Inclusive channels SSA (E06-010, E05-015, E07-013) Target SSA: inclusive {sup 3}He(e,e) quasi-elastic scattering; Target SSA: inclusive {sup 3}He(e,e) deep inelastic-elastic scattering; New SIDIS experiments planned in Hall-A for JLab-12 GeV.

  6. Precise quantization of anomalous Hall effect near zero magnetic field

    SciTech Connect (OSTI)

    Bestwick, A. J.; Fox, E. J.; Kou, Xufeng; Pan, Lei; Wang, Kang L.; Goldhaber-Gordon, D.

    2015-05-04

    In this study, we report a nearly ideal quantum anomalous Hall effect in a three-dimensional topological insulator thin film with ferromagnetic doping. Near zero applied magnetic field we measure exact quantization in the Hall resistance to within a part per 10,000 and a longitudinal resistivity under 1 Ω per square, with chiral edge transport explicitly confirmed by nonlocal measurements. Deviations from this behavior are found to be caused by thermally activated carriers, as indicated by an Arrhenius law temperature dependence. Using the deviations as a thermometer, we demonstrate an unexpected magnetocaloric effect and use it to reach near-perfect quantization by cooling the sample below the dilution refrigerator base temperature in a process approximating adiabatic demagnetization refrigeration.

  7. Fractionally charged skyrmions in fractional quantum Hall effect

    SciTech Connect (OSTI)

    Balram, Ajit C.; Wurstbauer, U.; Wójs, A.; Pinczuk, A.; Jain, J. K.

    2015-11-26

    The fractional quantum Hall effect has inspired searches for exotic emergent topological particles, such as fractionally charged excitations, composite fermions, abelian and nonabelian anyons and Majorana fermions. Fractionally charged skyrmions, which support both topological charge and topological vortex-like spin structure, have also been predicted to occur in the vicinity of 1/3 filling of the lowest Landau level. The fractional skyrmions, however, are anticipated to be exceedingly fragile, suppressed by very small Zeeman energies. Here we show that, slightly away from 1/3 filling, the smallest manifestations of the fractional skyrmion exist in the excitation spectrum for a broad range of Zeeman energies, and appear in resonant inelastic light scattering experiments as well-defined resonances slightly below the long wavelength spin wave mode. The spectroscopy of these exotic bound states serves as a sensitive tool for investigating the residual interaction between composite fermions, responsible for delicate new fractional quantum Hall states in this filling factor region.

  8. Effects of Enhanced Eathode Electron Emission on Hall Thruster Operation

    SciTech Connect (OSTI)

    Y. Raitses, A. Smirnov and N. J. Fisch

    2009-04-24

    Interesting discharge phenomena are observed that have to do with the interaction between the magnetized Hall thruster plasma and the neutralizing cathode. The steadystate parameters of a highly ionized thruster discharge are strongly influenced by the electron supply from the cathode. The enhancement of the cathode electron emission above its self-sustained level affects the discharge current and leads to a dramatic reduction of the plasma divergence and a suppression of large amplitude, low frequency discharge current oscillations usually related to an ionization instability. These effects correlate strongly with the reduction of the voltage drop in the region with the fringing magnetic field between the thruster channel and the cathode. The measured changes of the plasma properties suggest that the electron emission affects the electron cross-field transport in the thruster discharge. These trends are generalized for Hall thrusters of various configurations.

  9. Contactless measurement of alternating current conductance in quantum Hall structures

    SciTech Connect (OSTI)

    Drichko, I. L.; Diakonov, A. M.; Malysh, V. A.; Smirnov, I. Yu.; Ilyinskaya, N. D.; Usikova, A. A.; Galperin, Y. M.; Kummer, M.; Känel, H. von

    2014-10-21

    We report a procedure to determine the frequency-dependent conductance of quantum Hall structures in a broad frequency domain. The procedure is based on the combination of two known probeless methods—acoustic spectroscopy and microwave spectroscopy. By using the acoustic spectroscopy, we study the low-frequency attenuation and phase shift of a surface acoustic wave in a piezoelectric crystal in the vicinity of the electron (hole) layer. The electronic contribution is resolved using its dependence on a transverse magnetic field. At high frequencies, we study the attenuation of an electromagnetic wave in a coplanar waveguide. To quantitatively calibrate these data, we use the fact that in the quantum-Hall-effect regime the conductance at the maxima of its magnetic field dependence is determined by extended states. Therefore, it should be frequency independent in a broad frequency domain. The procedure is verified by studies of a well-characterized p-SiGe/Ge/SiGe heterostructure.

  10. Intermittency in Hall-magnetohydrodynamics with a strong guide field

    SciTech Connect (OSTI)

    Rodriguez Imazio, P.; Martin, L. N.; Dmitruk, P.; Mininni, P. D.; National Center for Atmospheric Research, P.O. Box 3000, Boulder, Colorado 80307

    2013-05-15

    We present a detailed study of intermittency in the velocity and magnetic field fluctuations of compressible Hall-magnetohydrodynamic turbulence with an external guide field. To solve the equations numerically, a reduced model valid when a strong guide field is present is used. Different values for the ion skin depth are considered in the simulations. The resulting data are analyzed computing field increments in several directions perpendicular to the guide field, and building structure functions and probability density functions. In the magnetohydrodynamic limit, we recover the usual results with the magnetic field being more intermittent than the velocity field. In the presence of the Hall effect, field fluctuations at scales smaller than the ion skin depth show a substantial decrease in the level of intermittency, with close to monofractal scaling.

  11. NE-24 Gilman Hall, University of California, Certification Documentation

    Office of Legacy Management (LM)

    Gilman Hall, University of California, Certification Documentation Berkeley, California, Conditional Verlette Gatlin, MA-232 I am attaching for entry into the Public Document Room, two copies of the subject documentation. These documents are the backup data for the conditional certification that the site is radiologically acceptable for restricted use as noted in the certification statement published in the Federal Register. Inasmuch as the conditional certification is made public through the

  12. Gradient instabilities of electromagnetic waves in Hall thruster plasma

    SciTech Connect (OSTI)

    Tomilin, Dmitry

    2013-04-15

    This paper presents a linear analysis of gradient plasma instabilities in Hall thrusters. The study obtains and analyzes the dispersion equation of high-frequency electromagnetic waves based on the two-fluid model of a cold plasma. The regions of parameters corresponding to unstable high frequency modes are determined and the dependence of the increments and intrinsic frequencies on plasma parameters is obtained. The obtained results agree with those of previously published studies.

  13. Quantum Hall effect in graphene decorated with disordered multilayer patches

    SciTech Connect (OSTI)

    Nam, Youngwoo; Sun, Jie Lindvall, Niclas; Kireev, Dmitry; Yurgens, August; Jae Yang, Seung; Rae Park, Chong; Woo Park, Yung

    2013-12-02

    Quantum Hall effect (QHE) is observed in graphene grown by chemical vapour deposition using platinum catalyst. The QHE is even seen in samples which are irregularly decorated with disordered multilayer graphene patches and have very low mobility (<500 cm{sup 2}V{sup −1}s{sup −1}). The effect does not seem to depend on electronic mobility and uniformity of the resulting material, which indicates the robustness of QHE in graphene.

  14. Transition in Electron Transport in a Cylindrical Hall Thruster

    SciTech Connect (OSTI)

    J.B. Parker, Y. Raitses, and N.J. Fisch

    2010-06-02

    Through the use of high-speed camera and Langmuir probe measurements in a cylindrical Hall thruster, we report the discovery of a rotating spoke of increased plasma density and light emission which correlates with increased electron transport across the magnetic field. As cathode electron emission is increased, a sharp transition occurs where the spoke disappears and electron transport decreases. This suggests that a significant fraction of the electron current might be directed through the spoke.

  15. Jackie Chen inducted into Alameda County Women's Hall of Fame

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

    inducted into Alameda County Women's Hall of Fame - 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 Waste

  16. Magnetic shielding of a laboratory Hall thruster. II. Experiments

    SciTech Connect (OSTI)

    Hofer, Richard R. Goebel, Dan M.; Mikellides, Ioannis G.; Katz, Ira

    2014-01-28

    The physics of magnetic shielding in Hall thrusters were validated through laboratory experiments demonstrating essentially erosionless, high-performance operation. The magnetic field near the walls of a laboratory Hall thruster was modified to effectively eliminate wall erosion while maintaining the magnetic field topology away from the walls necessary to retain efficient operation. Plasma measurements at the walls validate our understanding of magnetic shielding as derived from the theory. The plasma potential was maintained very near the anode potential, the electron temperature was reduced by a factor of two to three, and the ion current density was reduced by at least a factor of two. Measurements of the carbon backsputter rate, wall geometry, and direct measurement of plasma properties at the wall indicate that the wall erosion rate was reduced by a factor of 1000 relative to the unshielded thruster. These changes effectively eliminate wall erosion as a life limitation in Hall thrusters, enabling a new class of deep-space missions that could not previously be attempted.

  17. Metal-to-insulator switching in quantum anomalous Hall states

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

    Kou, Xufeng; Pan, Lei; Wang, Jing; Fan, Yabin; Choi, Eun Sang; Lee, Wei -Li; Nie, Tianxiao; Murata, Koichi; Shao, Qiming; Zhang, Shou -Cheng; et al

    2015-10-07

    After decades of searching for the dissipationless transport in the absence of any external magnetic field, quantum anomalous Hall effect (QAHE) was recently achieved in magnetic topological insulator films. However, the universal phase diagram of QAHE and its relation with quantum Hall effect (QHE) remain to be investigated. Here, we report the experimental observation of the giant longitudinal resistance peak and zero Hall conductance plateau at the coercive field in the six quintuple-layer (Cr0.12Bi0.26Sb0.62)2Te3 film, and demonstrate the metal-to-insulator switching between two opposite QAHE plateau states up to 0.3 K. Moreover, the universal QAHE phase diagram is confirmed through themore » angle-dependent measurements. Our results address that the quantum phase transitions in both QAHE and QHE regimes are in the same universality class, yet the microscopic details are different. Additionally, the realization of the QAHE insulating state unveils new ways to explore quantum phase-related physics and applications.« less

  18. Metal-to-insulator switching in quantum anomalous Hall states

    SciTech Connect (OSTI)

    Kou, Xufeng; Pan, Lei; Wang, Jing; Fan, Yabin; Choi, Eun Sang; Lee, Wei -Li; Nie, Tianxiao; Murata, Koichi; Shao, Qiming; Zhang, Shou -Cheng; Wang, Kang L.

    2015-10-07

    After decades of searching for the dissipationless transport in the absence of any external magnetic field, quantum anomalous Hall effect (QAHE) was recently achieved in magnetic topological insulator films. However, the universal phase diagram of QAHE and its relation with quantum Hall effect (QHE) remain to be investigated. Here, we report the experimental observation of the giant longitudinal resistance peak and zero Hall conductance plateau at the coercive field in the six quintuple-layer (Cr0.12Bi0.26Sb0.62)2Te3 film, and demonstrate the metal-to-insulator switching between two opposite QAHE plateau states up to 0.3 K. Moreover, the universal QAHE phase diagram is confirmed through the angle-dependent measurements. Our results address that the quantum phase transitions in both QAHE and QHE regimes are in the same universality class, yet the microscopic details are different. Additionally, the realization of the QAHE insulating state unveils new ways to explore quantum phase-related physics and applications.

  19. D0 Collision Hall Outdoor Fresh Air Makeup

    SciTech Connect (OSTI)

    Markley, D.; /Fermilab

    1992-03-27

    This note will briefly describe the collision hall ventilation system and how D0 will monitor outside air makeup and what actions occur in the event of system failures. The Dzero collision hall has two different fresh air makeup conditions it must meet. They are: (1) Tunnel Barriers removed-Fresh air makeup = 4500 CFM; and (2) Tunnel Barriers in place-Fresh air makeup = 2800 CFM. This note demonstrates how the fresh air minimums are met and guaranteed. The air flow paths and ducts at D0 for both AHU1 and EF-7 are fixed. The blower throughputs are not variable. The software stops on AHU1's dampers will be set for a minimum of 2800 cfm or 4500 cfm of outdoor air continuously added to the HVAC flow stream depending on the tunnel barrier state. AHU1 and EF-7 both have monitoring that can determine reliably as to whether the respective blower is on or off. Since the outside air makeup is fixed as long as the blowers are running, and the software AHU1 damper limits are set, we can rely on the blower status indicators to determine as to whether the collision hall is receiving the proper amount of outside makeup air.

  20. Physics and modeling of an end-Hall (gridless) ion source

    SciTech Connect (OSTI)

    Oudini, N.; Hagelaar, G. J. M.; Boeuf, J.-P.; Garrrigues, L.

    2011-04-01

    In an end-Hall source, an ion beam is extracted from a magnetized plasma and accelerated by the plasma electric field without grids. The principle of end-Hall sources is similar to that of Hall effect thrusters (or closed-drift thrusters), but their design is optimized for processing applications (ion beam assisted deposition or substrate cleaning) rather than propulsion. The beam divergence is larger in end-Hall ion sources, and these sources can operate at low ion energies. Although end-Hall sources are commonly used in the surface processing industry, no detailed modeling of these sources is available, and their operation is quite empirical. In this paper, a self-consistent, two-dimensional, quasineutral model of an end-Hall ion source is developed and used in order to improve the understanding of the basic physics of these plasma sources and to quantify the parameters controlling the properties of the extracted ion beam.

  1. June 24, 2015 in 100E Hildebrand Hall | Center for Gas SeparationsRele...

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

    4, 2015 in 100E Hildebrand Hall Previous Next List Stephen Meckler (Lawrence Berkeley National Laboratory) Layered Zif-Polymer Composites Accessed through Metal Oxide Precursors...

  2. Topological Hall conductivity of vortex and skyrmion spin textures

    SciTech Connect (OSTI)

    Jalil, M. B. A. Ghee Tan, Seng; Eason, Kwaku; Kong, Jian Feng

    2014-05-07

    We analyze the topological Hall conductivity experienced by conduction electrons whose spins are strongly coupled to axially symmetric spin textures, such as magnetic vortex and skyrmion of types I and II, theoretically by gauge theory, and numerically via micromagnetic simulations. The numerical results are in agreement with the theoretical predictions. Divergence between the two is seen when the vortex/skyrmion core radius is comparable or larger than the element size, and when the skyrmion configuration breaks down at high Dzyaloshinskii-Moriya interaction strength.

  3. Plasma lens and plume divergence in the Hall thruster

    SciTech Connect (OSTI)

    Fruchtman, A.; Cohen-Zur, A.

    2006-09-11

    The effect of magnetic field curvature on the plume divergence in the Hall thruster is analyzed. The two-dimensional plasma flow and electric field are determined self-consistently within the paraxial approximation in this plasma lens, a nearly axial electric field perpendicular to the curved magnetic field lines. The ion radial velocity along the thruster is described analytically. The authors suggest positioning the ionization layer near the zero of the magnetic field in a reversing-direction field configuration for a minimal beam divergence. They also show that an additional emitting electrode can reduce plume divergence.

  4. PREPRINT QUASIPARTICLE AGGREGATION I N THE FRACTIONAL QUANTUM HALL EFFECT

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

    91618 PREPRINT QUASIPARTICLE AGGREGATION I N THE FRACTIONAL QUANTUM HALL EFFECT R. B. Laughlin This paper was prepared for submittal to the Proceedings of the 17th International Conference on the Physics of Semi conductors San Francisco, California August 6-10, 1984 October 10, 1984 This is a preprint of a paper intended for publication in a journal or proceedings. Since changes may be made before publication, this preprint is made available with the un- derstanding that it will not be cited or

  5. Titanium diboride ceramic fiber composites for Hall-Heroult cells

    DOE Patents [OSTI]

    Besmann, T.M.; Lowden, R.A.

    1990-05-29

    An improved cathode structure is described for Hall-Heroult cells for the electrolytic production of aluminum metal. This cathode structure is a preform fiber base material that is infiltrated with electrically conductive titanium diboride using chemical vapor infiltration techniques. The structure exhibits good fracture toughness, and is sufficiently resistant to attack by molten aluminum. Typically, the base can be made from a mat of high purity silicon carbide fibers. Other ceramic or carbon fibers that do not degrade at temperatures below about 1000 C can be used.

  6. Titanium diboride ceramic fiber composites for Hall-Heroult cells

    DOE Patents [OSTI]

    Besmann, Theodore M.; Lowden, Richard A.

    1990-01-01

    An improved cathode structure for Hall-Heroult cells for the electrolytic production of aluminum metal. This cathode structure is a preform fiber base material that is infiltrated with electrically conductive titanium diboride using chemical vapor infiltration techniques. The structure exhibits good fracture toughness, and is sufficiently resistant to attack by molten aluminum. Typically, the base can be made from a mat of high purity silicon carbide fibers. Other ceramic or carbon fibers that do not degrade at temperatures below about 1000 deg. C can be used.

  7. Materials for Giant Spin Hall Device | Argonne National Laboratory

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

    Materials for Giant Spin Hall Device September 7, 2016 11:00AM to 12:00PM Presenter Avyaya Jayanthinarasimham, State University of New York-Albany Location Building 223, Room S105 Type Seminar Series MSD Seminar Abstract: Spin-orbit coupling in metastable β-W generates spin-orbit torques (SOTs) strong enough to flip the magnetic moment of an adjacent magnetic layer. In a magnetic tunnel junction (MTJ) stack, these torques can be used to switch between high and low resistive states. Deposition

  8. ,The Honorable Thomas Henino City Hall Plaza I

    Office of Legacy Management (LM)

    Department of Energy Washington,. DC 20585 MAR 29 1995 ,The Honorable Thomas Henino City Hall Plaza I Boston, Massachusetts 02201 '. ! Dear Mayor Menino: Even though additional involvement by DOE is,not necessary at this site, we are prepared to respond to any concerns you may have. -' : __ if you have any questions,' please feel free to call me eat 301-427li721 or Dr. W. Alexander Willlams (301-427-1719)~of my staff. ' gyp , ,~.&.Qz J ~ J / d .!~a : T- " ames W. Wagoner I -. Secretary

  9. Vortex equations governing the fractional quantum Hall effect

    SciTech Connect (OSTI)

    Medina, Luciano

    2015-09-15

    An existence theory is established for a coupled non-linear elliptic system, known as “vortex equations,” describing the fractional quantum Hall effect in 2-dimensional double-layered electron systems. Via variational methods, we prove the existence and uniqueness of multiple vortices over a doubly periodic domain and the full plane. In the doubly periodic situation, explicit sufficient and necessary conditions are obtained that relate the size of the domain and the vortex numbers. For the full plane case, existence is established for all finite-energy solutions and exponential decay estimates are proved. Quantization phenomena of the magnetic flux are found in both cases.

  10. Hall magnetohydrodynamic reconnection in the plasmoid unstable regime

    SciTech Connect (OSTI)

    Baalrud, S. D.; Bhattacharjee, A.; Huang, Y.-M.; Germaschewski, K.

    2011-09-15

    A set of reduced Hall magnetohydrodynamic (MHD) equations are used to evaluate the stability of large aspect ratio current sheets to the formation of plasmoids (secondary islands). Reconnection is driven by resistivity in this analysis, which occurs at the resistive skin depth d{sub {eta}}{identical_to}S{sub L}{sup -1/2}{radical}(L{nu}{sub A}/{gamma}), where S{sub L} is the Lundquist number, L, the length of the current sheet, {nu}{sub A,} the Alfven speed, and {gamma}, the growth rate. Modifications to a recent resistive MHD analysis [N. F. Loureiro et al., Phys. Plasmas 14, 100703 (2007)] arise when collisions are sufficiently weak that d{sub {eta}} is shorter than the ion skin depth d{sub i}{identical_to}c/{omega}{sub pi}. Secondary islands grow faster in this Hall MHD regime: the maximum growth rate scales as (d{sub i}/L){sup 6/13}S{sub L}{sup 7/13}{nu}{sub A}/L and the number of plasmoids as (d{sub i}/L){sup 1/13}S{sub L}{sup 11/26}, compared to S{sub L}{sup 1/4}{nu}{sub A}/L and S{sup 3/8}, respectively, in resistive MHD.

  11. Fractionally charged skyrmions in fractional quantum Hall effect

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

    Balram, Ajit C.; Wurstbauer, U.; Wójs, A.; Pinczuk, A.; Jain, J. K.

    2015-11-26

    The fractional quantum Hall effect has inspired searches for exotic emergent topological particles, such as fractionally charged excitations, composite fermions, abelian and nonabelian anyons and Majorana fermions. Fractionally charged skyrmions, which support both topological charge and topological vortex-like spin structure, have also been predicted to occur in the vicinity of 1/3 filling of the lowest Landau level. The fractional skyrmions, however, are anticipated to be exceedingly fragile, suppressed by very small Zeeman energies. Here we show that, slightly away from 1/3 filling, the smallest manifestations of the fractional skyrmion exist in the excitation spectrum for a broad range of Zeemanmore » energies, and appear in resonant inelastic light scattering experiments as well-defined resonances slightly below the long wavelength spin wave mode. The spectroscopy of these exotic bound states serves as a sensitive tool for investigating the residual interaction between composite fermions, responsible for delicate new fractional quantum Hall states in this filling factor region.« less

  12. Hall effect in quantum critical charge-cluster glass

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

    Bozovic, Ivan; Wu, Jie; Bollinger, Anthony T.; Sun, Yujie

    2016-04-04

    Upon doping, cuprates undergo a quantum phase transition from an insulator to a d-wave superconductor. The nature of this transition and of the insulating state is vividly debated. Here, we study the Hall effect in La2-xSrxCuO4 (LSCO) samples doped near the quantum critical point at x ≈ 0.06. Dramatic fluctuations in the Hall resistance appear below TCG ≈ 1.5 K and increase as the sample is cooled down further, signaling quantum critical behavior. We explore the doping dependence of this effect in detail, by studying a combinatorial LSCO library in which the Sr content is varied in extremely fine steps,more » Δx ≈ 0.00008. Furthermore, we observe that quantum charge fluctuations wash out when superconductivity emerges but can be restored when the latter is suppressed by applying a magnetic field, showing that the two instabilities compete for the ground state.« less

  13. Refrigeration Recovery for Experiment Hall High Target Loads

    SciTech Connect (OSTI)

    Peter Knudsen, Venkatarao Ganni, Errol Yuksek, Jonathan Creel

    2010-04-01

    The Qweak experiment at Jefferson Lab (JLab) is a 3000 W hydrogen target scheduled for the summer of 2010 and running for two years until the planned shut-down for 12GeV. The End Station Refrigerator (ESR) supports the three experiment halls, two of which may normally have a hydrogen target. The refrigerator for the ESR is a CTI/Helix 1500 W 4.5-K refrigerator nominally capable of supporting a 1250 W target load at 12 bar and 15-K (plus 1100 W of 4.5-K refrigeration). As such, this refrigerator is not capable of supporting the Qweak experiment target load in its present condition. Additionally, since the installation of an ambient air vaporizer for a single use, two week run duration of a high target load in the summer of 2003 there has been a consistent usage of the Central Helium Liquefier’s (CHL’s) 3 bar 4.5-K helium, supplied via an existing transfer-line to the ESR, for other high target loads. By the fall of 2004, it was apparent that this continued use of CHL’s supercritical helium was routinely being sought by the hall experimenters. As such, a method of refrigeration recovery was proposed to reduce the support required of CHL for these high target loads, including the anticipated Qweak experiment, while utilizing the recovered CHL refrigeration from the target to increase ESR’s 12 bar 15-K capacity.

  14. Magnetic shielding of walls from the unmagnetized ion beam in a Hall thruster

    SciTech Connect (OSTI)

    Mikellides, Ioannis G.; Katz, Ira; Hofer, Richard R.; Goebel, Dan M.

    2013-01-14

    We demonstrate by numerical simulations and experiments that the unmagnetized ion beam formed in a Hall thruster can be controlled by an applied magnetic field in a manner that reduces by 2-3 orders of magnitude deleterious ion bombardment of the containing walls. The suppression of wall erosion in Hall thrusters to such low levels has remained elusive for decades.

  15. Town Hall Slides 9.4.14 FINAL.pptx

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

    * Recovery Planning Activities - Tammy Reynolds * Closing Comments - Dana Bryson * Audience Questions * One question at a time please RECOVERY UPDATE Dana Bryson, Deputy...

  16. President Obama Talks Clean Energy At Facebook Town Hall | Department...

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

    and the purpose and impact of the 2009 Recovery Act: "We made the largest investment in history in clean energy research, and it's really paying off. For example, when I came...

  17. Town Hall Slides 3_27_14.pptx

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

    March 27, 2014 AGENDA ITEMS Joe Franco CBFO Manager Meeting Agenda * WIPP Status presentations * Tammy Reynolds * Fran Williams * Joe Franco * Audience Questions * One question at a time please * Final Remarks / Close WIPP RECOVERY PLAN ACTIVITIES Tammy Reynolds NWP Recovery Manager WIPP Recovery Plan Activities * Install a Continuous Air Monitor (CAM) at Station B * Provides real time radiological information on exhaust stack air * Installation to complete this week * One week run time to

  18. Town Hall Slides 4-10-14 FINAL.pptx

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

    0, 2014 Meeting Agenda *! Opening Comments - Mayor Janway *! Update on Entries, Additional Recovery Items - Dana Bryson, Tammy Reynolds *! Environmental Sampling - Stewart Jones *! Environmental Protection Agency *! Worth Noting - Dana Bryson *! Shipments to Waste Control Specialists *! Audience Questions *! One question at a time please UPDATE ON ENTRIES Dana Bryson, CBFO Deputy Manager Tammy Reynolds, NWP Deputy Recovery Manager Re-Entry Phase 1 Phase 2A Phase 2B Phase 3 *! Unmanned Entry *!

  19. Town_Hall_Slides_1_7_16.pdf

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

  20. Town_Hall_Slides_2_5_15.pdf

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

  1. Town_Hall_Slides_4_2_15.pdf

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

  2. Microsoft Word - UEC Town_Hall_Meeting_notes.docx

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

    * John Lange, Legislative Assistant to Congressman Robert Hurt, 5th District VA * Xan Fishman, Legislative Assistant to Congressman John Delany, 6th District MD * Erika Appel,...

  3. Town Hall Slides_6_19_14.pptx

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

    Three main options under consideration: 1. VJT tool using 2" titanium rods 2. Gantry camera 3. Existing process (pole and camera) VJT tool with titanium rods - Option 1 VJT tool ...

  4. Town_Hall_Slides_5_22_14.pptx

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

    22, 2014 Meeting Agenda * Opening Comments - Mayor Dale Janway * Panel Member Introductions - John Heaton (Moderator) * CBFO Manager Remarks - Joe Franco * Update on Phase 3 ...

  5. Town_Hall_Slides_5_8_14

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

    * Opening Comments - Mayor Janway * Panel Member Introductions - John Heaton ... will also collect additional samples from Panel 7 to help with the forensic analysis ...

  6. Town Hall Meeting #3: Green Button | OpenEI Community

    Open Energy Info (EERE)

    You must login in order to post into this group. Latest blog post comments Mike o spectacular dataset Posted: 9 Aug 2015 - 14:46 by: Mike o Calum Residential idf Files Posted:...

  7. Secretary Moniz Leads DOE Town Hall | Department of Energy

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

    Secretary Moniz and Deputy Secretary Poneman address questions from Department of Energy ... Secretary Moniz: Week One Watch the swearing-in ceremony. See a video recap of Secretary ...

  8. Microsoft Word - Town-Hall-meeting_2014.docx

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

    (LSPR) spectroscopy Jilai Ding Georgia Institute of Technology Poster 28, Study of Ionic Dynamics in Nanostructured Ceria through Lateral Electrochemical Measurements and Finite...

  9. Diversity Town Hall Draws a Crowd at the Energy Department

    Broader source: Energy.gov [DOE]

    “For our own good, we want as wide of a talent pool as we can get,” Secretary Steven Chu said in his remarks to employees. “[Diversity] is a good thing and an important thing to do. It’s also the right thing to do.”

  10. Missed the Town Hall with Secretary Chu? | Department of Energy

    Office of Environmental Management (EM)

    one million advanced technology vehicles on the road by 2015; A "Sun Shot" initiative to make solar energy cost-competitive with fossil-based fuels before the end of this ...

  11. Microsoft Word - Town-Hall-meeting_notes_090215.docx

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

    State Brian Long-U. Tennessee Yayoi Takamura-University of California, Davis Yang Zhang-U. Illinois (possibly Secretary) Milan Buncick- AEgis Technologies Vice Chair:...

  12. Quantitative analytical model for magnetic reconnection in hall magnetohydrodynamics

    SciTech Connect (OSTI)

    Simakov, Andrei N

    2008-01-01

    Magnetic reconnection is of fundamental importance for laboratory and naturally occurring plasmas. Reconnection usually develops on time scales which are much shorter than those associated with classical collisional dissipation processes, and which are not fully understood. While such dissipation-independent (or 'fast') reconnection rates have been observed in particle and Hall magnetohydrodynamics (MHD) simulations and predicted analytically in electron MHD, a quantitative analytical theory of fast reconnection valid for arbitrary ion inertial lengths d{sub i} has been lacking. Here we propose such a theory without a guide field. The theory describes two-dimensional magnetic field diffusion regions, provides expressions for the reconnection rates, and derives a formal criterion for fast reconnection in terms of dissipation parameters and di. It also demonstrates that both open X-point and elongated diffusion regions allow dissipation-independent reconnection and reveals a possibility of strong dependence of the reconnection rates on d{sub i}.

  13. A low-cost multiple Hall probe current transducer

    SciTech Connect (OSTI)

    Scoville, J.T.; Petersen, P.I. )

    1991-03-01

    An inexpensive but highly stable and accurate transducer has been developed for the measurement of large currents associated with the operation of the DIII-D tokamak at General Atomics. The inherent problems with integrator circuits required by Rogowski loops and the excessive cost of secondary compensation current'' devices have led to this development. The transducer requires several inexpensive Hall effect devices and a simple, stable, and linear interface circuit. Analysis of the initial performance characteristics is very encouraging and has led to several useful applications of the transducer to date, with plans for the installation of additional devices in the future. The low cost and reasonable accuracy of the transducer make it an attractive alternative to commercially available devices.

  14. Perturbation analysis of ionization oscillations in Hall effect thrusters

    SciTech Connect (OSTI)

    Hara, Kentaro Sekerak, Michael J.; Boyd, Iain D.; Gallimore, Alec D.

    2014-12-15

    A perturbation analysis of ionization oscillations, which cause low frequency oscillations of the discharge plasma, in Hall effect thrusters is presented including the electron energy equation in addition to heavy-species transport. Excitation and stabilization of such oscillations, often called the breathing mode, are discussed in terms of the growth rate obtained from the linear perturbation equations of the discharge plasma. The instability induced from the ionization occurs only when the perturbation in the electron energy is included while the neutral atom flow contributes to the damping of the oscillation. Effects of the electron energy loss mechanisms such as wall heat loss, inelastic collisions, and convective heat flux are discussed. It is shown that the ionization oscillations can be damped when the electron transport is reduced and the electron temperature increases so that the energy loss to the wall stabilizes the ionization instability.

  15. Hall MHD Stability and Turbulence in Magnetically Accelerated Plasmas

    SciTech Connect (OSTI)

    H. R. Strauss

    2012-11-27

    The object of the research was to develop theory and carry out simulations of the Z pinch and plasma opening switch (POS), and compare with experimental results. In the case of the Z pinch, there was experimental evidence of ion kinetic energy greatly in excess of the ion thermal energy. It was thought that this was perhaps due to fine scale turbulence. The simulations showed that the ion energy was predominantly laminar, not turbulent. Preliminary studies of a new Z pinch experiment with an axial magnetic field were carried out. The axial magnetic is relevant to magneto - inertial fusion. These studies indicate the axial magnetic field makes the Z pinch more turbulent. Results were also obtained on Hall magnetohydrodynamic instability of the POS.

  16. The Hall D solenoid helium refrigeration system at JLab

    SciTech Connect (OSTI)

    Laverdure, Nathaniel A.; Creel, Jonathan D.; Dixon, Kelly d.; Ganni, Venkatarao; Martin, Floyd D.; Norton, Robert O.; Radovic, Sasa

    2014-01-01

    Hall D, the new Jefferson Lab experimental facility built for the 12GeV upgrade, features a LASS 1.85 m bore solenoid magnet supported by a 4.5 K helium refrigerator system. This system consists of a CTI 2800 4.5 K refrigerator cold box, three 150 hp screw compressors, helium gas management and storage, and liquid helium and nitrogen storage for stand-alone operation. The magnet interfaces with the cryo refrigeration system through an LN2-shielded distribution box and transfer line system, both designed and fabricated by JLab. The distribution box uses a thermo siphon design to respectively cool four magnet coils and shields with liquid helium and nitrogen. We describe the salient design features of the cryo system and discuss our recent commissioning experience.

  17. Ultrahigh sensitivity of anomalous Hall effect sensor based on Cr-doped

    Office of Scientific and Technical Information (OSTI)

    Bi2Te3 topological insulator thin films (Journal Article) | SciTech Connect Ultrahigh sensitivity of anomalous Hall effect sensor based on Cr-doped Bi2Te3 topological insulator thin films Citation Details In-Document Search This content will become publicly available on July 1, 2017 Title: Ultrahigh sensitivity of anomalous Hall effect sensor based on Cr-doped Bi2Te3 topological insulator thin films Anomalous Hall effect (AHE) was recently discovered in magnetic element-doped topological

  18. Quantum Anomalous Hall Effect in Hg_1-yMn_yTe Quantum Wells

    SciTech Connect (OSTI)

    Liu, Chao-Xing; Qi, Xiao-Liang; Dai, Xi; Fang, Zhong; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.

    2010-03-19

    The quantum Hall effect is usually observed when the two-dimensional electron gas is subjected to an external magnetic field, so that their quantum states form Landau levels. In this work we predict that a new phenomenon, the quantum anomalous Hall effect, can be realized in Hg{sub 1-y}Mn{sub y}Te quantum wells, without the external magnetic field and the associated Landau levels. This effect arises purely from the spin polarization of the Mn atoms, and the quantized Hall conductance is predicted for a range of quantum well thickness and the concentration of the Mn atoms. This effect enables dissipationless charge current in spintronics devices.

  19. Formation of quantum spin Hall state on Si surface and energy gap scaling

    Office of Scientific and Technical Information (OSTI)

    with strength of spin orbit coupling (Journal Article) | SciTech Connect Formation of quantum spin Hall state on Si surface and energy gap scaling with strength of spin orbit coupling Citation Details In-Document Search Title: Formation of quantum spin Hall state on Si surface and energy gap scaling with strength of spin orbit coupling For potential applications in spintronics and quantum computing, it is desirable to place a quantum spin Hall insulator [i.e., a 2D topological insulator

  20. All electrical manipulation of magnetization dynamics in a ferromagnet by antiferromagnets with anisotropic spin Hall effects.

    SciTech Connect (OSTI)

    Zhang, Wei; Jungfleisch, Matthias B.; Freimuth, Frank; Jiang, Wanjun; Sklenar, Joseph; Pearson, John E.; Ketterson, John B.; Mokrousov, Yuri; Hoffmann, Axel

    2015-10-06

    We investigate spin-orbit torques of metallic CuAu-I-type antiferromagnets using spin-torque ferromagnetic resonance tuned by a dc-bias current. The observed spin torques predominantly arise from diffusive transport of spin current generated by the spin Hall effect. We find a growth-orientation dependence of the spin torques by studying epitaxial samples, which may be correlated to the anisotropy of the spin Hall effect. The observed anisotropy is consistent with first-principles calculations on the intrinsic spin Hall effect. Our work suggests large tunable spin-orbit effects in magnetically-ordered materials.

  1. TBA-0042 - In the Matter of Curtis Hall | Department of Energy

    Office of Environmental Management (EM)

    42 - In the Matter of Curtis Hall TBA-0042 - In the Matter of Curtis Hall This Decision considers two Appeals of an Initial Agency Decision (IAD) issued on March 15, 2007, by a Hearing Officer in the Department of Energy's (DOE) Office of Hearings and Appeals (OHA). The IAD addressed the merits of a whistleblower complaint filed by Curtis Hall against his former employer, Bechtel National, Inc. (BNI), under the Department of Energy's Contractor Employee Protection Program, 10 C.F.R. Part 708.

  2. Electron Cross-field Transport in a Low Power Cylindrical Hall Thruster

    SciTech Connect (OSTI)

    A. Smirnov; Y. Raitses; N.J. Fisch

    2004-06-24

    Conventional annular Hall thrusters become inefficient when scaled to low power. Cylindrical Hall thrusters, which have lower surface-to-volume ratio, are therefore more promising for scaling down. They presently exhibit performance comparable with conventional annular Hall thrusters. Electron cross-field transport in a 2.6 cm miniaturized cylindrical Hall thruster (100 W power level) has been studied through the analysis of experimental data and Monte Carlo simulations of electron dynamics in the thruster channel. The numerical model takes into account elastic and inelastic electron collisions with atoms, electron-wall collisions, including secondary electron emission, and Bohm diffusion. We show that in order to explain the observed discharge current, the electron anomalous collision frequency {nu}{sub B} has to be on the order of the Bohm value, {nu}{sub B} {approx} {omega}{sub c}/16. The contribution of electron-wall collisions to cross-field transport is found to be insignificant.

  3. Formation of quantum spin Hall state on Si surface and energy...

    Office of Scientific and Technical Information (OSTI)

    Si surface and energy gap scaling with strength of spin orbit coupling Title: Formation of quantum spin Hall state on Si surface and energy gap scaling with strength of spin orbit ...

  4. Beam Position Reconstruction for the g2p Experiment in Hall A...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Beam Position Reconstruction for the g2p Experiment in Hall A at Jefferson Lab Citation Details In-Document Search Title: Beam Position Reconstruction for the g2p...

  5. Anomalous Hall effect in magnetic disordered alloys: Effects of spin orbital coupling

    SciTech Connect (OSTI)

    Ma, L.; Gao, W. B.; Zhou, S. M.; Shi, Z.; He, P.; Miao, J.; Jiang, Y.

    2013-12-28

    For disordered ternary Fe{sub 0.5}(Pd{sub 1−x}Pt{sub x}){sub 0.5} alloy films, the anomalous Hall effect obeys the conventional scaling law ρ{sub AH}=aρ{sub xx}+bρ{sub xx}{sup 2} with the longitudinal resistivity ρ{sub xx} and anomalous Hall resistivity ρ{sub AH}. Contributed by the intrinsic term and the extrinsic side-jump one, the scattering-independent anomalous Hall conductivity b increases with increasing Pt/Pd concentration. In contrast, the skew scattering parameter a is mainly influenced by the residual resistivity. The present results will facilitate the theoretical studies of the anomalous Hall effect in magnetic disordered alloys.

  6. Metallization and Hall-effect of Mg{sub 2}Ge under high pressure

    SciTech Connect (OSTI)

    Li, Yuqiang; Gao, Yang; Han, Yonghao Liu, Cailong; Peng, Gang; Ke, Feng; Gao, Chunxiao; Wang, Qinglin; Ma, Yanzhang

    2015-10-05

    The electrical transport properties of Mg{sub 2}Ge under high pressure were studied with the in situ temperature-dependent resistivity and Hall-effect measurements. The theoretically predicted metallization of Mg{sub 2}Ge was definitely found around 7.4 GPa by the temperature-dependent resistivity measurement. Other two pressure-induced structural phase transitions were also reflected by the measurements. Hall-effect measurement showed that the dominant charge carrier in the metallic Mg{sub 2}Ge was hole, indicating the “bad metal” nature of Mg{sub 2}Ge. The Hall mobility and charge carrier concentration results pointed out that the electrical transport behavior in the antifluorite phase was controlled by the increase quantity of drifting electrons under high pressure, but in both anticotunnite and Ni{sub 2}In-type phases it was governed by the Hall mobility.

  7. Quantification of the spin-Hall anti-damping torque with a resonance spectrometer

    SciTech Connect (OSTI)

    Emori, Satoru Nan, Tianxiang; Oxholm, Trevor M.; Boone, Carl T.; Sun, Nian X.; Jones, John G.; Howe, Brandon M.; Brown, Gail J.; Budil, David E.

    2015-01-12

    We present a simple technique using a cavity-based resonance spectrometer to quantify the anti-damping torque due to the spin Hall effect. Modification of ferromagnetic resonance is observed as a function of small DC current in sub-mm-wide strips of bilayers, consisting of magnetically soft FeGaB and strong spin-Hall metal Ta. From the detected current-induced linewidth change, we obtain an effective spin Hall angle of 0.08–0.09 independent of the magnetic layer thickness. Our results demonstrate that a sensitive resonance spectrometer can be a general tool to investigate spin Hall effects in various material systems, even those with vanishingly low conductivity and magnetoresistance.

  8. The Honoradle':Rudolf Juiliani City'Hall New York, New York I0007

    Office of Legacy Management (LM)

    Wasthgton, DC 20585 ' ,,' . .' . . s ,' FEi,l 6 jg& ,. . . ' I s. i ,-' .' ,, -. ,. The Honoradle':Rudolf Juiliani City'Hall New York, New York I0007 i ', 1" Dear ...

  9. After 105 Years, Historic City Hall in West Des Moines, Iowa...

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

    ... credit: Vicky Saylor EECBG Success Story: After 105 Years, Historic City Hall in West Des Moines, Iowa Goes Green Using money from the Energy Efficiency Block Grant Program, St. ...

  10. Out With the Old, In With the New: New Hampshire Town to Upgrade...

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

    Newfields, New Hampshire's town hall has a lot of old-time charm worth keeping, with its steeple, rusted-red brick and chimney stacks, but the town lights are ready for a makeover. ...

  11. Micromagnetic study of auto-oscillation modes in spin-Hall nano-oscillators

    SciTech Connect (OSTI)

    Ulrichs, H. Demidov, V. E.; Demokritov, S. O.

    2014-01-27

    We present a numerical study of magnetization dynamics in a recently introduced spin torque nano-oscillator, whose operational principle relies on the spin-Hall effect—spin-Hall nano-oscillators. Our numerical results show good agreement with the experimentally observed behaviors and provide detailed information about the features of the primary auto-oscillation mode observed in the experiments. They also clarify the physical nature of the secondary auto-oscillation mode, which was experimentally observed under certain conditions only.

  12. Concept for Reducing Hall Thruster Chamber Wall Erosion with Lithium Vapor

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

    Shielding. | Princeton Plasma Physics Lab Concept for Reducing Hall Thruster Chamber Wall Erosion with Lithium Vapor Shielding. Hall thrusters have been established as a compact and reliable means for satellite applications. Erosion of the surfaces of such thrusters, however, has been a serious factor in limiting their lifetimes. Replacing eroded surfaces by replenishing them is generally unattractive because of the mechanical complexity and added weight that could be required. This

  13. Habitat Restoration/Enhancement Fort Hall Reservation : 2008 Annual Report.

    SciTech Connect (OSTI)

    Osborne, Hunter

    2009-07-23

    Habitat enhancement, protection and monitoring were the focus of the Resident Fisheries Program during 2008. Enhancement and protection included sloping, fencing and planting wetlands plugs at sites on Spring Creek (Head-waters). Many previously constructed instream structures (rock barbs and wing dams) were repaired throughout the Fort Hall Indian Reservation (Reservation). Physical sampling during 2008 included sediment and depth measurements (SADMS) in Spring Creek at the Car Removal site. SADMS, used to track changes in channel morphology and specifically track movements of silt through Bottoms stream systems were completed for 5 strata on Spring Creek. Water temperature and chemistry were monitored monthly on Spring Creek, Clear Creek, Diggie Creek, and Portneuf (Jimmy Drinks) and Blackfoot rivers. Fish population densities and biomass were sampled in five reservation streams which included nine sites. Sampling protocols were identical to methods used in past years. Numbers of fish in Spring Creek series remained relatively low, however, there was an increase of biomass overall since 1993. Salmonid fry densities were monitored near Broncho Bridge and were similar to 2006, and 2007, however, as in years past, high densities of macrophytes make it very difficult to see fry in addition to lack of field technicians. Mean catch rate by anglers on Bottoms streams stayed the same as 2007 at 1.5/hr. Numbers of fish larger than 18-inches caught by anglers increased from 2007 at .20 to .26/hr.

  14. Magnetoresistance, electrical conductivity, and Hall effect of glassy carbon

    SciTech Connect (OSTI)

    Baker, D.F.

    1983-02-01

    These properties of glassy carbon heat treated for three hours between 1200 and 2700/sup 0/C were measured from 3 to 300/sup 0/K in magnetic fields up to 5 tesla. The magnetoresistance was generally negative and saturated with reciprocal temperature, but still increased as a function of magnetic field. The maximum negative magnetoresistance measured was 2.2% for 2700/sup 0/C material. Several models based on the negative magnetoresistance being proportional to the square of the magnetic moment were attempted; the best fit was obtained for the simplest model combining Curie and Pauli paramagnetism for heat treatments above 1600/sup 0/C. Positive magnetoresistance was found only in less than 1600/sup 0/C treated glassy carbon. The electrical conductivity, of the order of 200 (ohm-cm)/sup -1/ at room temperature, can be empirically written as sigma = A + Bexp(-CT/sup -1/4) - DT/sup -1/2. The Hall coefficient was independent of magnetic field, insensitive to temperature, but was a strong function of heat treatment temperature, crossing over from negative to positive at about 1700/sup 0/C and ranging from -0.048 to 0.126 cm/sup 3//coul. The idea of one-dimensional filaments in glassy carbon suggested by the electrical conductivity is compatible with the present consensus view of the microstructure.

  15. Fractional quantum Hall junctions and two-channel Kondo models

    SciTech Connect (OSTI)

    Sandler, Nancy P.; Fradkin, Eduardo

    2001-06-15

    A mapping between fractional quantum Hall (FQH) junctions and the two-channel Kondo model is presented. We discuss this relation in detail for the particular case of a junction of a FQH state at {nu}=1/3 and a normal metal. We show that in the strong coupling regime this junction has a non-Fermi-liquid fixed point. At this fixed point the electron Green{close_quote}s function has a branch cut and the impurity entropy is equal to S=1/2ln2. We construct the space of perturbations at the strong coupling fixed point and find that the dimension of the tunneling operator is 1/2. These properties are strongly reminiscent of the non-Fermi-liquid fixed points of a number of quantum impurity models, particularly the two-channel Kondo model. However we have found that, in spite of these similarities, the Hilbert spaces of these two systems are quite different. In particular, although in a special limit the Hamiltonians of both systems are the same, their Hilbert spaces are not since they are determined by physically distinct boundary conditions. As a consequence the spectrum of operators in the two problems is different.

  16. Effects of wall electrodes on Hall effect thruster plasma

    SciTech Connect (OSTI)

    Langendorf, S. Walker, M.; Xu, K.

    2015-02-15

    This paper investigates the physical mechanisms that cause beneficial and detrimental performance effect observed to date in Hall effect thrusters with wall electrodes. It is determined that the wall electrode sheath can reduce ion losses to the wall if positioned near the anode (outside the dense region of the plasma) such that an ion-repelling sheath is able to form. The ability of the wall electrode to form an ion-repelling sheath is inversely proportional to the current drawn—if the wall electrode becomes the dominant sink for the thruster discharge current, increases in wall electrode bias result in increased local plasma potential rather than an ion-repelling sheath. A single-fluid electron flow model gives results that mimic the observed potential structures and the current-sharing fractions between the anode and wall electrodes, showing that potential gradients in the presheath and bulk plasma come at the expense of current draw to the wall electrodes. Secondary electron emission from the wall electrodes (or lack thereof) is inferred to have a larger effect if the electrodes are positioned near the exit plane than if positioned near the anode, due to the difference in energy deposition from the plasma.

  17. Onset of fast reconnection in Hall magnetohydrodynamics mediated by the plasmoid instability

    SciTech Connect (OSTI)

    Huang Yimin; Bhattacharjee, A.; Sullivan, Brian P.

    2011-07-15

    The role of a super-Alfvenic plasmoid instability in the onset of fast reconnection is studied by means of the largest Hall magnetohydrodynamics simulations to date, with system sizes up to 10{sup 4} ion skin depths (d{sub i}). It is demonstrated that the plasmoid instability can facilitate the onset of rapid Hall reconnection, in a regime where the onset would otherwise be inaccessible because the Sweet-Parker width is significantly above d{sub i}. However, the topology of Hall reconnection is not inevitably a single stable X-point. There exists an intermediate regime where the single X-point topology itself exhibits instability, causing the system to alternate between a single X-point geometry and an extended current sheet with multiple X-points produced by the plasmoid instability. Through a series of simulations with various system sizes relative to d{sub i}, it is shown that system size affects the accessibility of the intermediate regime. The larger the system size is, the easier it is to realize the intermediate regime. Although our Hall magnetohydrodynamics (MHD) model lacks many important physical effects included in fully kinetic models, the fact that a single X-point geometry is not inevitable raises the interesting possibility for the first time that Hall MHD simulations may have the potential to realize reconnection with geometrical features similar to those seen in fully kinetic simulations, namely, extended current sheets and plasmoid formation.

  18. Magnetic shielding of Hall thrusters at high discharge voltages

    SciTech Connect (OSTI)

    Mikellides, Ioannis G. Hofer, Richard R.; Katz, Ira; Goebel, Dan M.

    2014-08-07

    A series of numerical simulations and experiments have been performed to assess the effectiveness of magnetic shielding in a Hall thruster operating in the discharge voltage range of 300–700 V (I{sub sp} ≈ 2000–2700 s) at 6 kW, and 800 V (I{sub sp} ≈ 3000) at 9 kW. At 6 kW, the magnetic field topology with which highly effective magnetic shielding was previously demonstrated at 300 V has been retained for all other discharge voltages; only the magnitude of the field has been changed to achieve optimum thruster performance. It is found that magnetic shielding remains highly effective for all discharge voltages studied. This is because the channel is long enough to allow hot electrons near the channel exit to cool significantly upon reaching the anode. Thus, despite the rise of the maximum electron temperature in the channel with discharge voltage, the electrons along the grazing lines of force remain cold enough to eliminate or reduce significantly parallel gradients of the plasma potential near the walls. Computed maximum erosion rates in the range of 300–700 V are found not to exceed 10{sup −2} mm/kh. Such rates are ∼3 orders of magnitude less than those observed in the unshielded version of the same thruster at 300 V. At 9 kW and 800 V, saturation of the magnetic circuit did not allow for precisely the same magnetic shielding topology as that employed during the 6-kW operation since this thruster was not designed to operate at this condition. Consequently, the maximum erosion rate at the inner wall is found to be ∼1 order of magnitude higher (∼10{sup −1} mm/kh) than that at 6 kW. At the outer wall, the ion energy is found to be below the sputtering yield threshold so no measurable erosion is expected.

  19. Spin Hall magnetoresistance in CoFe2O4/Pt films

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

    Wu, Hao; Qintong, Zhang; Caihua, Wan; Ali, Syed Shahbaz; Yuan, Zhonghui; You, Lu; Wang, Junling; Choi, Yongseong; Han, Xiufeng

    2015-05-13

    Pulse laser deposition and magnetron sputtering techniques have been employed to prepare MgO(001)//CoFe2O4/Pt samples. Cross section transmission electron microscope results prove that the CoFe2O4 film epitaxially grew along (001) direction. X-ray magnetic circular dichroism results show that magnetic proximity effect in this sample is negligible. Magnetoresistance (MR) properties confirm that spin Hall MR (SMR) dominates in this system. Spin Hall effect-induced anomalous Hall voltage was also observed in this sample. Lastly, these results not only demonstrate the universality of SMR effect but also demonstrate the utility in spintronics of CoFe2O4 as a new type of magnetic insulator.

  20. Fractional quantum Hall effect at Landau level filling ν = 4/11

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

    Pan, W.; Baldwin, K. W.; West, K. W.; Pfeiffer, L. N.; Tsui, D. C.

    2015-01-09

    In this study, we report low temperature electronic transport results on the fractional quantum Hall effect of composite fermions at Landau level filling ν = 4/11 in a very high mobility and low density sample. Measurements were carried out at temperatures down to 15mK, where an activated magnetoresistance Rxx and a quantized Hall resistance Rxy, within 1% of the expected value of h/(4/11)e2, were observed. The temperature dependence of the Rxx minimum at 4/11 yields an activation energy gap of ~ 7 mK. Developing Hall plateaus were also observed at the neighboring states at ν = 3/8 and 5/13.

  1. Experimental Observation of the Inverse Spin Hall Effect at Room Temperature

    SciTech Connect (OSTI)

    Liu, Baoli; Shi, Junren; Wang, Wenxin; Zhao, Hongming; Li, Dafang; Zhang, Shoucheng; Xue, Qikun; Chen, Dongmin; /Beijing, Inst. Phys.

    2010-03-16

    We observe the inverse spin Hall effect in a two-dimensional electron gas confined in Al-GaAs/InGaAs quantum wells. Specifically, they find that an inhomogeneous spin density induced by the optical injection gives rise to an electric current transverse to both the spin polarization and its gradient. The spin Hall conductivity can be inferred from such a measurement through the Einstein relation and the onsager relation, and is found to have the order of magnitude of 0.5(e{sup 2}/h). The observation is made at the room temperature and in samples with macroscopic sizes, suggesting that the inverse spin Hall effects is a robust macroscopic transport phenomenon.

  2. Driving and detecting ferromagnetic resonance in insulators with the spin Hall effect.

    SciTech Connect (OSTI)

    Sklenar, Joseph; Zhang, Wei; Jungfleisch, Matthias B.; Jiang, Wanjun; Chang, Houchen; Pearson, John E.; Wu, Mingzhong; Ketterson, John B.; Hoffmann, Axel

    2015-11-06

    We demonstrate the generation and detection of spin-torque ferromagnetic resonance in Pt/Y3Fe5O12 (YIG) bilayers. A unique attribute of this system is that the spin Hall effect lies at the heart of both the generation and detection processes and no charge current is passing through the insulating magnetic layer. When the YIG undergoes resonance, a dc voltage is detected longitudinally along the Pt that can be described by two components. One is the mixing of the spin Hall magnetoresistance with the microwave current. The other results from spin pumping into the Pt being converted to a dc current through the inverse spin Hall effect. The voltage is measured with applied magnetic field directions that range in-plane to nearly perpendicular. We find that for magnetic fields that are mostly out-of-plane, an imaginary component of the spin mixing conductance is required to model our data.

  3. Ultra-sensitive Hall sensors based on graphene encapsulated in hexagonal boron nitride

    SciTech Connect (OSTI)

    Dauber, Jan; Stampfer, Christoph; Sagade, Abhay A.; Neumaier, Daniel; Oellers, Martin; Watanabe, Kenji; Taniguchi, Takashi

    2015-05-11

    The encapsulation of graphene in hexagonal boron nitride provides graphene on substrate with excellent material quality. Here, we present the fabrication and characterization of Hall sensor elements based on graphene boron nitride heterostructures, where we gain from high mobility and low charge carrier density at room temperature. We show a detailed device characterization including Hall effect measurements under vacuum and ambient conditions. We achieve a current- and voltage-related sensitivity of up to 5700 V/AT and 3 V/VT, respectively, outpacing state-of-the-art silicon and III/V Hall sensor devices. Finally, we extract a magnetic resolution limited by low frequency electric noise of less than 50 nT/√(Hz) making our graphene sensors highly interesting for industrial applications.

  4. Engineering the quantum anomalous Hall effect in graphene with uniaxial strains

    SciTech Connect (OSTI)

    Diniz, G. S. Guassi, M. R.; Qu, F.

    2013-12-28

    We theoretically investigate the manipulation of the quantum anomalous Hall effect (QAHE) in graphene by means of the uniaxial strain. The values of Chern number and Hall conductance demonstrate that the strained graphene in presence of Rashba spin-orbit coupling and exchange field, for vanishing intrinsic spin-orbit coupling, possesses non-trivial topological phase, which is robust against the direction and modulus of the strain. Besides, we also find that the interplay between Rashba and intrinsic spin-orbit couplings results in a topological phase transition in the strained graphene. Remarkably, as the strain strength is increased beyond approximately 7%, the critical parameters of the exchange field for triggering the quantum anomalous Hall phase transition show distinct behaviors—decrease (increase) for strains along zigzag (armchair) direction. Our findings open up a new platform for manipulation of the QAHE by an experimentally accessible strain deformation of the graphene structure, with promising application on novel quantum electronic devices with high efficiency.

  5. Quantum Hall effect in semiconductor systems with quantum dots and antidots

    SciTech Connect (OSTI)

    Beltukov, Ya. M.; Greshnov, A. A.

    2015-04-15

    The integer quantum Hall effect in systems of semiconductor quantum dots and antidots is studied theoretically as a factor of temperature. It is established that the conditions for carrier localization in quantum-dot systems favor the observation of the quantum Hall effect at higher temperatures than in quantum-well systems. The obtained numerical results show that the fundamental plateau corresponding to the transition between the ground and first excited Landau levels can be retained up to a temperature of T ∼ 50 K, which is an order of magnitude higher than in the case of quantum wells. Implementation of the quantum Hall effect at such temperatures requires quantum-dot systems with controllable characteristics, including the optimal size and concentration and moderate geometrical and composition fluctuations. In addition, ordered arrangement is desirable, hence quantum antidots are preferable.

  6. Fractional quantum Hall effect at Landau level filling ν = 4/11

    SciTech Connect (OSTI)

    Pan, W.; Baldwin, K. W.; West, K. W.; Pfeiffer, L. N.; Tsui, D. C.

    2015-01-09

    In this study, we report low temperature electronic transport results on the fractional quantum Hall effect of composite fermions at Landau level filling ν = 4/11 in a very high mobility and low density sample. Measurements were carried out at temperatures down to 15mK, where an activated magnetoresistance Rxx and a quantized Hall resistance Rxy, within 1% of the expected value of h/(4/11)e2, were observed. The temperature dependence of the Rxx minimum at 4/11 yields an activation energy gap of ~ 7 mK. Developing Hall plateaus were also observed at the neighboring states at ν = 3/8 and 5/13.

  7. Global Hall-MHD simulations of magnetorotational instability in a plasma Couette flow experiment

    SciTech Connect (OSTI)

    Ebrahimi, F.; Lefebvre, B.; Bhattacharjee, A.; Forest, C. B.

    2011-06-15

    Global MHD and Hall-MHD numerical simulations relevant to the Madison plasma Couette flow experiment (MPCX) have been performed using the extended MHD code NIMROD. The MPCX has been constructed to study the magnetorotational instability (MRI) in a plasma. The two-fluid Hall effect, which is relevant to some astrophysical situations such as protostellar disks, is also expected to be important in the MPCX. Here, we first derive the local Hall dispersion relation including viscosity, extending earlier work by Balbus and Terquem [Astrophys. J. 552, 235 (2001)]. The predictions of the local analysis are then compared with nonlocal calculations of linear stability of the MRI for a parameter range relevant to the MPCX. It is found that the MHD stability limit and mode structure are altered by the Hall term, and nonlocal analysis is necessary to obtain quantitatively reliable predictions for MPCX. Two-fluid physics also significantly changes the nonlinear evolution and saturation of the axisymmetric MRI. Both the Reynolds and Maxwell stresses contribute significantly to momentum transport. In the Hall regime, when the magnetic field is parallel to the rotation axis, the Maxwell stress is larger than the Reynolds stress (similar to the MHD regime). However, when the magnetic field is antiparallel to the rotation axis in the Hall regime, the Reynolds stress is much larger than the Maxwell stress. To further study the role of non-axisymmetric modes, we have also carried out fully nonlinear MHD computations. Non-axisymmetric modes play an increasingly important role as the magnetic Reynolds number increases and grow to large amplitudes in a saturated turbulent state.

  8. Hysteretic magnetoresistance and unconventional anomalous Hall effect in the frustrated magnet TmB4

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

    Sunku, Sai Swaroop; Kong, Tai; Ito, Toshimitsu; Canfield, Paul C.; Shastry, B. Sriram; Sengupta, Pinaki; Panagopoulos, Christos

    2016-05-11

    We study TmB4, a frustrated magnet on the Archimedean Shastry-Sutherland lattice, through magnetization and transport experiments. The lack of anisotropy in resistivity shows that TmB4 is an electronically three-dimensional system. The magnetoresistance (MR) is hysteretic at low temperature even though a corresponding hysteresis in magnetization is absent. The Hall resistivity shows unconventional anomalous Hall effect (AHE) and is linear above saturation despite a large MR. In conclusion, we propose that complex structures at magnetic domain walls may be responsible for the hysteretic MR and may also lead to the AHE.

  9. Spin Hall effect-controlled magnetization dynamics in NiMnSb

    SciTech Connect (OSTI)

    Dürrenfeld, P. Ranjbar, M.; Gerhard, F.; Gould, C.; Molenkamp, L. W.; Åkerman, J.

    2015-05-07

    We investigate the influence of a spin current generated from a platinum layer on the ferromagnetic resonance (FMR) properties of an adjacent ferromagnetic layer composed of the halfmetallic half-Heusler material NiMnSb. Spin Hall nano-oscillator devices are fabricated, and the technique of spin torque FMR is used to locally study the magnetic properties as in-plane anisotropies and resonance fields. A change in the FMR linewidth, in accordance with the additional spin torque produced by the spin Hall effect, is present for an applied dc current. For sufficiently large currents, this should yield auto-oscillations, which however are not achievable in the present device geometry.

  10. Experimental evidences of a large extrinsic spin Hall effect in AuW alloy

    SciTech Connect (OSTI)

    Laczkowski, P.; Rojas-Sánchez, J.-C.

    2014-04-07

    We report an experimental study of a gold-tungsten alloy (7 at. % W concentration in Au host) displaying remarkable properties for spintronics applications using both magneto-transport in lateral spin valve devices and spin-pumping with inverse spin Hall effect experiments. A very large spin Hall angle of about 10% is consistently found using both techniques with the reliable spin diffusion length of 2 nm estimated by the spin sink experiments in the lateral spin valves. With its chemical stability, high resistivity, and small induced damping, this AuW alloy may find applications in the nearest future.

  11. Spin-torque switching of a nano-magnet using giant spin hall effect

    SciTech Connect (OSTI)

    Penumatcha, Ashish V. Das, Suprem R.; Chen, Zhihong; Appenzeller, Joerg

    2015-10-15

    The Giant Spin Hall Effect(GSHE) in metals with high spin-orbit coupling is an efficient way to convert charge currents to spin currents, making it well-suited for writing information into magnets in non-volatile magnetic memory as well as spin-logic devices. We demonstrate the switching of an in-plane CoFeB magnet using a combination of GSHE and an external magnetic field. The magnetic field dependence of the critical current is used to estimate the spin hall angle with the help of a thermal activation model for spin-transfer torque switching of a nanomagnet.

  12. JLab mourns loss of long-time colleague, Hall B staff scientist and senior

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

    YerPI physicist Kim Egiyan | Jefferson Lab long-time colleague, Hall B staff scientist and senior YerPI physicist Kim Egiyan JLab mourns loss of long-time colleague, Hall B staff scientist and senior YerPI physicist Kim Egiyan August 25, 2006 Kim Egiyan Kim Egiyan K.Sh. Egiyan was born on 18 June 1935 in the Armenian village of Mirzik in the Khanlar region of Azerbaijan. Kim attended the Yerevan State University, Yerevan (Armenia) and in 1957, after finishing his studies at the university,

  13. JLab, Physics Community Mourns Death of Jean Mougey, First Hall...

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

    Lab, and a director of the Nuclear Physics Division at CEA Saclay, passed away from a heart attack on Nov. 5, 2015, in Grenoble. Jean was born in the French town of Angers, by...

  14. Equivalence of donor and acceptor fits of temperature dependent Hall carrier density and Hall mobility data: Case of ZnO

    SciTech Connect (OSTI)

    Brochen, Stphane; Feuillet, Guy; Pernot, Julien

    2014-04-28

    In this work, statistical formulations of the temperature dependence of ionized and neutral impurity concentrations in a semiconductor, needed in the charge balance equation and for carrier scattering calculations, have been developed. These formulations have been used in order to elucidate a confusing situation, appearing when compensating acceptor (donor) levels are located sufficiently close to the conduction (valence) band to be thermally ionized and thereby to emit (capture) an electron to (from) the conduction (valence) band. In this work, the temperature dependent Hall carrier density and Hall mobility data adjustments are performed in an attempt to distinguish the presence of a deep acceptor or a deep donor level, coexisting with a shallower donor level and located near the conduction band. Unfortunately, the present statistical developments, applied to an n-type hydrothermal ZnO sample, lead in both cases to consistent descriptions of experimental Hall carrier density and mobility data and thus do not allow to determine the nature, donor or acceptor, of the deep level. This demonstration shows that the emission of an electron in the conduction band, generally assigned to a (0/+1) donor transition from a donor level cannot be applied systematically and could also be attributed to a (?1/0) donor transition from an acceptor level. More generally, this result can be extended for any semiconductor and also for deep donor levels located close to the valence band (acceptor transition)

  15. EX/P5-4 Two-Fluid Hall Effect on Plasma Relaxation

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

    EXP5-4 Two-Fluid Hall Effect on Plasma Relaxation in a High-Temperature Plasma W.X. Ding 1,3), V. Mirnov 2,3), A. F. Almagri 2,3), D.L. Brower 1,3), D. Craig 2,3), B.H. Deng 1,3), ...

  16. Internal plasma potential measurements of a Hall thruster using plasma lens focusing

    SciTech Connect (OSTI)

    Linnell, Jesse A.; Gallimore, Alec D.

    2006-10-15

    Magnetic field topology has been found to be a central design concern for high-efficiency Hall thrusters. For future improvements in Hall thruster design, it is necessary to better understand the effects that magnetic field topology has on the internal plasma structure. The Plasmadynamics and Electric Propulsion Laboratory's High-speed Axial Reciprocating Probe system is used in conjunction with a floating emissive probe to map the internal plasma potential structure of the NASA-173Mv1 Hall thruster [R. R. Hofer, R. S. Jankovsky, and A. D. Gallimore, J. Propul. Power 22, 721 (2006); 22, 732 (2006)]. Measurements are taken at 300 and 500 V with a xenon propellant. Electron temperature and electric field are also measured and reported. The acceleration zone and equipotential lines are found to be strongly linked to the magnetic field lines. Moreover, in some cases the ions are accelerated strongly toward the center of the discharge channel. The agreement between magnetic field lines and equipotential lines is best for high-voltage operation. These results have strong implications on the performance and lifetime optimization of Hall thrusters.

  17. The impact of Hall physics on magnetized high energy density plasma jets

    SciTech Connect (OSTI)

    Gourdain, P.-A.; Seyler, C. E.; Atoyan, L.; Greenly, J. B.; Hammer, D. A.; Kusse, B. R.; Pikuz, S. A.; Potter, W. M.; Schrafel, P. C.; Shelkovenko, T. A.

    2014-05-15

    Hall physics is often neglected in high energy density plasma jets due to the relatively high electron density of such jets (n{sub e} ∼ 10{sup 19} cm{sup −3}). However, the vacuum region surrounding the jet has much lower densities and is dominated by Hall electric field. This electric field redirects plasma flows towards or away from the axis, depending on the radial current direction. A resulting change in the jet density has been observed experimentally. Furthermore, if an axial field is applied on the jet, the Hall effect is enhanced and ignoring it leads to serious discrepancies between experimental results and numerical simulations. By combining high currents (∼1 MA) and magnetic field helicity (15° angle) in a pulsed power generator such as COBRA, plasma jets can be magnetized with a 10 T axial field. The resulting field enhances the impact of the Hall effect by altering the density profile of current-free plasma jets and the stability of current-carrying plasma jets (e.g., Z-pinches)

  18. A novel method of including Landau level mixing in numerical studies of the quantum Hall effect

    SciTech Connect (OSTI)

    Wooten, Rachel; Quinn, John; Macek, Joseph

    2013-12-04

    Landau level mixing should influence the quantum Hall effect for all except the strongest applied magnetic fields. We propose a simple method for examining the effects of Landau level mixing by incorporating multiple Landau levels into the Haldane pseudopotentials through exact numerical diagonalization. Some of the resulting pseudopotentials for the lowest and first excited Landau levels will be presented.

  19. WIPP Employee Inducted Into Mine Rescue Hall of Fame- WIPP Teams Recognized at National Competition

    Broader source: Energy.gov [DOE]

    CARLSBAD, N.M., August 2, 2013 - Long-time Waste Isolation Pilot Plant (WIPP) employee Gary Kessler was inducted into the Metal/Non-Metal National Mine Rescue Hall of Fame on Aug. 1, 2013 at the biennial mine rescue competition in Reno, Nevada.

  20. EECBG Success Story: After 105 Years, Historic City Hall in West Des Moines, Iowa Goes Green

    Broader source: Energy.gov [DOE]

    The city of West Des Moines, Iowa is used funding to renovate the Historic City Hall building located in Valley Junction, including the installation of four geothermal heating wells, a rooftop covered with vegetation, solar panels and permeable pavers to allow stormwater through to the soil below. Learn more.

  1. Analysis of Impacts of a Clean Energy Standard as requested by Chairman Hall

    Reports and Publications (EIA)

    2011-01-01

    This report responds to a request from Chairman Ralph M. Hall for an analysis of the impacts of a Clean Energy Standard (CES). The request, as outlined in the letter included in Appendix A, sets out specific assumptions and scenarios for the study.

  2. Structure transitions induced by the Hall term in homogeneous and isotropic magnetohydrodynamic turbulence

    SciTech Connect (OSTI)

    Miura, H., E-mail: miura.hideaki@nifs.ac.jp [Department of Helical Plasma Research, National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Araki, K. [Faculty of Engineering, Okayama University of Science, 1-1 Ridai-cho, Okayama 700-0005 (Japan)

    2014-07-15

    Hall effects on local structures in homogeneous, isotropic, and incompressible magnetohydrodynamic turbulence are studied numerically. The transition of vortices from sheet-like to tubular structures induced by the Hall term is found, while the kinetic energy spectrum does not distinguish the two types of structures. It is shown by the use of the sharp low-pass filter that the transition occurs not only in the scales smaller than the ion skin depth but also in a larger scale. The transition is related with the forward energy transfer in the spectral space. Analyses by the use of the sharp low-pass filter show that the nonlinear energy transfer associated with the Hall term is dominated by the forward transfer and relatively local in the wave number space. A projection of the simulation data to a Smagorinsky-type sub-grid-scale model shows that the high wave number component of the Hall term may possibly be replaced by the model effectively.

  3. Hall effect in the extremely large magnetoresistance semimetal WTe{sub 2}

    SciTech Connect (OSTI)

    Luo, Yongkang Dai, Y. M.; Taylor, A. J.; Yarotski, D. A.; Prasankumar, R. P.; Thompson, J. D.; Li, H.; Miao, H.; Shi, Y. G.; Ding, H.

    2015-11-02

    We systematically measured the Hall effect in the extremely large magnetoresistance semimetal WTe{sub 2}. By carefully fitting the Hall resistivity to a two-band model, the temperature dependencies of the carrier density and mobility for both electron- and hole-type carriers were determined. We observed a sudden increase in the hole density below ∼160 K, which is likely associated with the temperature-induced Lifshitz transition reported by a previous photoemission study. In addition, a more pronounced reduction in electron density occurs below 50 K, giving rise to comparable electron and hole densities at low temperature. Our observations indicate a possible electronic structure change below 50 K, which might be the direct driving force of the electron-hole “compensation” and the extremely large magnetoresistance as well. Numerical simulations imply that this material is unlikely to be a perfectly compensated system.

  4. Minimum energy states of the cylindrical plasma pinch in single-fluid and Hall magnetohydrodynamics

    SciTech Connect (OSTI)

    Khalzov, I. V.; Schnack, D. D.; Mirnov, V. V.; Ebrahimi, F.

    2012-01-15

    Relaxed states of a plasma column are found analytically in single-fluid and Hall magnetohydrodynamics (MHD). We perform complete minimization of the energy with constraints imposed by invariants inherent in the corresponding models. It is shown that the relaxed state in Hall MHD is a force-free magnetic field with uniform axial flow and/or rigid azimuthal rotation. In contrast, the relaxed states in single-fluid MHD are more complex due to the coupling between velocity and magnetic field. Cylindrically and helically symmetric relaxed states are considered for both models. Helical states may be time dependent and analogous to helical waves, propagating on a cylindrically symmetric background. Application of our results to reversed-field pinches (RFP) is discussed. The radial profile of the parallel momentum predicted by the single-fluid MHD relaxation theory is shown to be in reasonable agreement with experimental observation from the Madison symmetric torus RFP experiment.

  5. Variational principle for linear stability of flowing plasmas in Hall magnetohydrodynamics

    SciTech Connect (OSTI)

    Hirota, M.; Yoshida, Z.; Hameiri, E.

    2006-02-15

    Linear stability of equilibrium states with flow is studied by means of the variational principle in Hall magnetohydrodynamics (MHD). The Lagrangian representation of the linearized Hall MHD equation is performed by considering special perturbations that preserves some constants of motion (the Casimir invariants). The resultant equation has a Hamiltonian structure which enables the variational principle. There is however some difficulties in showing the positive definiteness of the quadratic form in the presence of flow. The dynamically accessible variation is a more restricted class of perturbations which, by definition, preserves all the Casimir invariants. For such variations, the quadratic form (the second variation of Hamiltonian) can be positive definite. Some conditions for stability are derived by applying this variational principle to the double Beltrami equilibrium.

  6. Determination of the Pt spin diffusion length by spin-pumping and spin Hall effect

    SciTech Connect (OSTI)

    Zhang, Wei; Pearson, John E.; Hoffmann, Axel; Vlaminck, Vincent; Divan, Ralu; Bader, Samuel D.

    2013-12-09

    The spin diffusion length of Pt at room temperature and at 8 K is experimentally determined via spin pumping and spin Hall effect in permalloy/Pt bilayers. Voltages generated during excitation of ferromagnetic resonance from the inverse spin Hall effect and anisotropic magnetoresistance effect were investigated with a broadband approach. Varying the Pt layer thickness gives rise to an evolution of the voltage line shape due to the superposition of the above two effects. By studying the ratio of the two voltage components with the Pt layer thickness, the spin diffusion length of Pt can be directly extracted. We obtain a spin diffusion length of ∼1.2 nm at room temperature and ∼1.6 nm at 8 K.

  7. Edge-channel interferometer at the graphene quantum Hall pn junction

    SciTech Connect (OSTI)

    Morikawa, Sei; Moriya, Rai; Masubuchi, Satoru Machida, Tomoki; Watanabe, Kenji; Taniguchi, Takashi

    2015-05-04

    We demonstrate a quantum Hall edge-channel interferometer in a high-quality graphene pn junction under a high magnetic field. The co-propagating p and n quantum Hall edge channels traveling along the pn interface functions as a built-in Aharonov-Bohm-type interferometer, the interferences in which are sensitive to both the external magnetic field and the carrier concentration. The trajectories of peak and dip in the observed resistance oscillation are well reproduced by our numerical calculation that assumes magnetic flux quantization in the area enclosed by the co-propagating edge channels. Coherent nature of the co-propagating edge channels is confirmed by the checkerboard-like pattern in the dc-bias and magnetic-field dependences of the resistance oscillations.

  8. Magnetic shielding of the channel walls in a Hall plasma accelerator

    SciTech Connect (OSTI)

    Mikellides, Ioannis G.; Katz, Ira; Hofer, Richard R.; Goebel, Dan M.; Grys, Kristi de; Mathers, Alex

    2011-03-15

    In a qualification life test of a Hall thruster it was found that the erosion of the acceleration channel practically stopped after {approx}5600 h. Numerical simulations using a two-dimensional axisymmetric plasma solver with a magnetic field-aligned mesh reveal that when the channel receded from its early-in-life to its steady-state configuration the following changes occurred near the wall: (1) reduction of the electric field parallel to the wall that prohibited ions from acquiring significant impact kinetic energy before entering the sheath, (2) reduction of the potential fall in the sheath that further diminished the total energy ions gained before striking the material, and (3) reduction of the ion number density that decreased the flux of ions to the wall. All these changes, found to have been induced by the magnetic field, constituted collectively an effective shielding of the walls from any significant ion bombardment. Thus, we term this process in Hall thrusters 'magnetic shielding'.

  9. Sheath oscillation characteristics and effect on near-wall conduction in a krypton Hall thruster

    SciTech Connect (OSTI)

    Zhang, Fengkui Kong, Lingyi; Li, Chenliang; Yang, Haiwei; Li, Wei

    2014-11-15

    Despite its affordability, the krypton Hall-effect thruster in applications always had problems in regard to performance. The reason for this degradation is studied from the perspective of the near-wall conductivity of electrons. Using the particle-in-cell method, the sheath oscillation characteristics and its effect on near-wall conduction are compared in the krypton and xenon Hall-effect thrusters both with wall material composed of BNSiO{sub 2}. Comparing these two thrusters, the sheath in the krypton-plasma thruster will oscillate at low electron temperatures. The near-wall conduction current is only produced by collisions between electrons and wall, thereby causing a deficiency in the channel current. The sheath displays spatial oscillations only at high electron temperature; electrons are then reflected to produce the non-oscillation conduction current needed for the krypton-plasma thruster. However, it is accompanied with intensified oscillations.

  10. Chemical reaction at ferromagnet/oxide interface and its influence on anomalous Hall effect

    SciTech Connect (OSTI)

    Liu, Yi-Wei; Teng, Jiao E-mail: ghyu@mater.ustb.edu.cn; Zhang, Jing-Yan; Liu, Yang; Chen, Xi; Li, Xu-Jing; Feng, Chun; Wang, Hai-Cheng; Li, Ming-Hua; Yu, Guang-Hua E-mail: ghyu@mater.ustb.edu.cn; Wu, Zheng-Long

    2014-09-08

    Chemical reactions at the ferromagnet/oxide interface in [Pt/Fe]{sub 3}/MgO and [Pt/Fe]{sub 3}/SiO{sub 2} multilayers before and after annealing were investigated by X-ray photoelectron spectroscopy. The results show that Fe atoms at the Fe/MgO interface were completely oxidized in the as-grown state and significantly deoxidized after vacuum annealing. However, only some of the Fe atoms at the Fe/SiO{sub 2} interface were oxidized and rarely deoxidized after annealing. The anomalous Hall effect was modified by this interfacial chemical reaction. The saturation anomalous Hall resistance (R{sub xy}) was greatly increased in the [Pt/Fe]{sub 3}/MgO multilayers after annealing and was 350% higher than that in the as-deposited film, while R{sub xy} of the [Pt/Fe]{sub 3}/SiO{sub 2} multilayer only increased 10% after annealing.