Energy and Climate

Introduction

The Solid-State Lighting Science Energy Frontier Research Center includes more than 30 participants who are conducting long-range, fundamental research on the science that underlies solid-state lighting.

Although most of the research is conducted at Sandia National Laboratories, the EFRC includes important collaborations with our external partners at the University of New Mexico, Northwestern University, Los Alamos National Laboratory, Philips LumiLEDS, California Institute of Technology, University of California at Irvine, University of California at Merced, and University of California at Santa Barbara.

EFRC Management Team

Photo of Mike Coltrin
Mike Coltrin
Director Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Mike Coltrinis a Distinguished Member of the Technical Staff in the Advanced Materials Sciences Department at Sandia National Laboratories in Albuquerque, NM . His primary research interests are modeling the growth of semiconductor thin films with applications to solid-state lighting. Coltrin received his Ph.D. in Physical Chemistry at the University of Illinois with Rudolph Marcus (Nobel Laureate, 1992). Coltrin joined Sandia National Laboratories in 1979, and initiated a very successful program in modeling Chemical Vapor Deposition (CVD) processes sponsored by Basic Energy Sciences. In 1984, he published the first detailed numerical model to simulate the coupled fluid flow, transport, gas-phase and surface chemistry during this very complex process. That paper was recognized as one of the 25-most cited papers in the 60-year history of the Journal of the Electrochemical Society; his combined work has been cited about 4,000 times. Today, there are more than one hundred people worldwide using his approach to design, optimize, understand, and control CVD systems. In his career, Dr. Coltrin has advanced a detailed understanding of the chemical reaction mechanisms in the growth of silicon, diamond, and, most recently, the gas-phase chemistry in group-III nitride growth. In addition, to detailed numerical simulations, his interests have also turned to developing simpler analytical models related to thin-film growth. He has successfully applied this approach to understanding morphology evolution in polycrystalline materials, scaling laws in rotating-disk CVD reactors, and transport effects in selective-area growth. In the course of his research modeling chemically reacting flows, Dr. Coltrin has been very involved in software development. He is the principal author and architect of the Surface Chemkin software, as well as several CVD reactor-modeling codes. Surface Chemkin is a package complementary to gas-phase Chemkin, and was designed to handle the details of heterogeneous, gas/surface reactions. The collection of chemically reacting flow software has been licensed to Reaction Design, Inc., who distributes the software commercially. Dr. Coltrin is a Fellow of the American Physical Society and the American Association for the Advancement of Science. He has authored or co-authored over 90 journal publications, 200 conference presentations (including about 60 invited talks), 3 U.S. patents, and a graduate textbook entitled Chemically Reacting Flow: Theory and Practice, published by Wiley Interscience (2003).

Education and Training

B. S. in Chemistry, Oklahoma State University, Stillwater, OK, 1975 M. S. in Physical Chemistry, University of Illinois, Urbana, IL, 1977 Ph. D. in Physical Chemistry, University of Illinois, Urbana, IL, 1979

Research and Professional Experience

Sandia National Laboratories, Member of the Technical Staff (8/1979 – present) University of Illinois, Graduate Research Assistant, Teaching Assistant (8/1975 – 7/1979) Phillips Petroleum Co., Bartlesville, OK, Analytical Chemistry (Summers 1974, 1975) University of Texas at Austin, Undergraduate Research Fellow (Summer 1973)

Selected Publications

“Mass Transport in the Epitaxial Lateral Overgrowth of Gallium Nitride,” C. C. Mitchell, M. E. Coltrin, and J. Han, J. Cryst. Growth, 222, 144 (2001). “Mass Transport and Kinetic Limitations in MOCVD Selective Area Growth,” M. E. Coltrin and C. C. Mitchell, J. Cryst. Growth, 254, 35 (2003). “Scaling Relationships for Analyzing Kinetics in GaN Epitaxial Lateral Overgrowth,” M. E. Coltrin and C. C. Mitchell, J. Cryst. Growth, 261, 30 (2004). “Understanding GaN Nucleation Layer Evolution on Sapphire,” D. D. Koleske, M. E. Coltrin, K. C. Cross, C. C. Mitchell, and A. A. Allerman, J. Cryst. Growth, 273, 86 (2004). “Using optical reflectance to measure GaN nucleation layer decomposition layer kinetics,” D. D. Koleske, M. E. Coltrin, M. J. Russell, J. Cryst. Growth, 279, 37 (2005). “Systematic Prediction of Kinetically Limited Crystal Growth Morphologies,” D. Du, D. J. Srolovitz, M. E. Coltrin, and C. C. Mitchell, Phys. Rev. Lett., 95, 155503/1-4 (2005). “Modeling the Parasitic Chemical Reactions of AlGaN OMVPE,” M. E. Coltrin, J. R. Creighton, and C. C. Mitchell, J. Cryst. Growth, 287, 566 (2006). “Fundamental Chemistry and Modeling of Group-III Nitride MOVPE,” J. R. Creighton, G. T. Wang, and M. E. Coltrin, J. Cryst. Growth, 298,2 (2007). “Beyond the Vacuum Tube: Lighting Solutions for the 21st Century,” J. A. Simmons, M. E. Coltrin, and J. Y. Tsao, Optics and Photonics News, 18, 14 (2007). “Research Challenges to Ultra-Efficient Inorganic Solid-State Lighting,” J. M. Phillips, M. E. Coltrin, M. H. Crawford, A. J. Fischer, M. R. Krames, R. Mueller-Mach, G. O. Mueller, Y. Ohno, L. E. S. Rohwer, J. A. Simmons, and J. Y. Tsao, Lasers and Photonics Reviews, 1 (4), 307 (2007).

Synergistic Activities

Principal Investigator for the “National Laboratory Center for Solid-State Lighting R&D” (funded by the DOE Office of Energy Efficiency and Renewable Energy), 2006-2008. Principal Investigator for the research project “Strain-Engineered InGaN for Deep-Green Light Emission” (funded by the DOE Office of Energy Efficiency and Renewable Energy), 2006-2008. Co-investigator on the projects: “Nanostructural Engineering of Nitride Nucleation Layers for GaN Substrate Dislocation Reduction,” “Nanowire Templated Lateral Epitaxial Growth of Low Dislocation Density GaN,” and “Improved InGaN Epitaxial Quality by Optimizing Growth Chemistry,” (funded by the DOE Office of Energy Efficiency and Renewable Energy), 2006-present Co-chair SPIE Photonics Asia “Solid-State Lighting Symposium,” Beijing, China, 11/2007. Author of “Solid-State Lighting Technology Perspective” for BES Workshop on Basic Research Needs for Solid-State Lighting,” 2006.

Categories: EFRC Management Team, Energy, Energy Efficiency, Solid State Lighting
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Photo of Jerry Simmons
Jerry Simmons
Chair: Senior Leadership Council for the SSLS EFRC Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Jerry Simmons is the Deputy Director for Semiconductor and Optical Sciences of the Center for Physical, Chemical, and Nano-Sciences at Sandia National Laboratories.  This Center is the premiere organization for fundamental science research at Sandia, and is composed of approximately seventy-five Ph. D. scientists and fifty other technical personnel. Jerry received Bachelor of Arts degrees in Philosophy in 1981 and in Physics in 1982, both from New College of Florida.  He then worked from 1982-1984 as a technician in the Optoelectronic Device Department under Mort Panish at Bell Laboratories, Murray Hill.  Jerry then attended graduate school at Princeton University, where he received a Master’s degree in 1986 and   Ph.D. in 1990, both in Electrical Engineering.  Jerry’s dissertation work was on the fractional quantum Hall effect (FQHE), where he reported the first direct evidence for the existence of fractionally charged particles.  (Jerry’s thesis advisor Dan Tsui was awarded the 1998 Nobel Prize in Physics.) Jerry joined Sandia National Laboratories as a Senior Member of Technical Staff in 1990.  Jerry’s technical interests are in the integer and fractional quantum Hall effects, low temperature electronic transport, nanophotonics, nanoelectronics and quantum electronics, detectors and emitters in the TeraHertz frequency range, solid state lighting, gallium nitride-based semiconductors, and the development of high brightness LEDs, edge-emitting lasers, and vertical cavity surface emitting lasers (VCSELs) in the green to the deep UV (250 nm).  Jerry became manager of the Semiconductor Material and Device Sciences Department in 2000, where he served as Program Manager for the $8.3M Solid State Lighting Grand Challenge LDRD Project.  In addition, he was program manager for a DARPA project on deep UV LEDs for chem.-bio detection, a joint LANL/SNL nanoscience LDRD on Active Photonic Nanostructures, and a DOE/Basic Energy Sciences project on Interacting Nanoelectronic and Nanophotonic Structures.  He has also managed several internal projects in the area of semiconductor physics, including terahertz frequency quantum cascade lasers and detectors, Bloch oscillations produced in lateral semiconductor superlattices, and excitonic Bose condensates at low temperatures. In 2004 Jerry assumed his present position, where he oversees Sandia’s portfolio of DOE/Basic Energy Sciences materials science research projects ($9M/year), and serves as a liaison to the DOD military technology business units at Sandia.  In this position he also has managed the Nanoscience-to-Microsystems area of Sandia’s $150M/year Laboratory Directed R&D (LDRD) program, and has served as Acting Co-Director of the DOE Center for Integrated Nanotechnologies (CINT), one of five DOE Nanoscale Science Research Centers. Jerry has authored over 100 publications, has 3 patents, and serves as a reviewer for NSF, DOE, APS, the Physical Review, and several other institutions and scientific journals.  He received an Industry Week Technology of the Year Award in 1998 for the invention of a quantum tunneling transistor, and is a Fellow of the American Physical Society and the American Association for the Advancement of Science.  He was organizer and Chair of the 16thInternational Conference on the Electronic Properties of Two-Dimensional Systems (EP2DS-16), held in Albuquerque, New Mexico, 2005.

Education and Training

B. A., Philosophy (Honors), New College of the University of South Florida, Sarasota, FL, 1981 B. A., Physics (Honors), New College of the University of South Florida, Sarasota, FL, 1982 M. A., Electrical Engineering, Princeton University, Princeton, NJ, 1986 Ph. D., Electrical Engineering, Princeton University, Princeton, NJ, 1990 Thesis:  “Resistance Fluctuations and Charge Measurements in Narrow AlGaAs/ GaAs Heterostructures in the Integral and Fractional Quantum Hall Regimes”Obtained first direct evidence for the existence of fractionally charged particles in the fractional quantum Hall effect. Advisor:  Prof. Dan C. Tsui, 1998 Nobel Laureate in Physics

Research and Professional Experience

Sandia National Laboratories, Senior Manager/Deputy Director, (4/2004 – present) Sandia National Laboratories, Acting Co-Director, Center for Integrated Nanotechnologies (5/2007 – 10/2007) Sandia National Laboratories, Manager, Semiconductor Materials and Device Sciences Department (5/2000 – 4/2004) Sandia National Laboratories, Member of Technical Staff (9/1990 – 5/2000) Adjunct Asst. Professor, Dept. of Physics, Univ. of New Mexico, Albuquerque, NM (1998 – 2002) Research/Teaching Assistant, Dept. of Electrical Engineering, Princeton Univ., (1984-1990) Senior Technical Associate, Physics and Chemistry Research Division, Bell Laboratories, Murray Hill, NJ,  Semiconductor physics technician.  (1982 -1982)

Selected Publications

“Beyond the Vacuum Tube: Lighting Solutions for the 21st Century,” J. A. Simmons, M. E. Coltrin, and J. Y. Tsao, Optics and Photonics News, 18, 14 (2007). “Research Challenges to Ultra-Efficient Inorganic Solid-State Lighting,” J. M. Phillips, M. E. Coltrin, M. H. Crawford, A. J. Fischer, M. R. Krames, R. Mueller-Mach, G. O. Mueller, Y. Ohno, L. E. S. Rohwer, J. A. Simmons, and J. Y. Tsao, Lasers and Photonics Reviews, 1 (4), 307 (2007). “InGaN/GaN quantum-well heterostructure light-emitting diodes employing photonic crystal structures, J. J. Wierer, M. R. Krames, J. E. Epler, M. G. Craford, J. R. Wendt, J. A. Simmons, M. M. Sigalas, Applied Physics Letters; 84 (19), 3885 (2004). “Prospects for LED lighting,” J. M. Gee, J. Y. Tsao, J. A. SimmonsProceedings of the SPIE – The International Society for Optical Engineering:  Third International Conference on Solid State Lighitng, 5187 (1), 227 (2004). “Interaction corrections to two-dimensional hole transport in the large-r{sub s} limit,” H. Noh, M. P. Lilly, D. C. Tsui, J. A. Simmons, E. H. Hwang, S. Das Sarma, L. N. Pfeiffer, K. W. West, Physical Review B 68 (16), 165308 (2003). “Terahertz photoconductivity and plasmon modes in double-quantum-well field-effect transistors,” X. G. Peralta, S. J. Allen, M. C. Wanke, N. E. Harff, J. A. Simmons, M. P. Lilly, J. L. Reno, P. J. Burke, J. P. Eisenstiein, Applied Physics Letters 81 (9), 1627 (2002). “Materials for solid state lighting,” S. G. Johnson, J. A. Simmons, Materials Research Society Symposium Proceedings: Symposia on Materials and Devices for Optoelectronics and Photonics/Photonic Crystals – From Materials to Devices, 722, 53 (2002).

Synergistic Activities

Lab Program Coordinator, Basic Energy Sciences/ Division of Materials Science & Engineering Core Program, 2004 – present.   Oversee and BES/DMS&E research activities at SNL/NM and SNL/CA. Program Manager for Sandia’s Solid State Lighting R&D Program, October 2000 – present.  Oversee all of Sandia’s R&D activities in SSL, at ~$5M/year; develop new business with numerous federal agency and private industrial customers; and serve as public educational resource on SSL.  Activities include:

  • Program Manager for Sandia’s “Grand Challenge” Laboratory Directed R&D (LDRD) Project, 2000 – 2004.  This $8.1M project involved 30-40 Sandia personnel, several external collaborations, and a stellar external advisory board.
  • Coordinator of Sandia projects under DOE/Energy Efficiency and Renewable Energy SSL Core Technology program, 2001 – present.  Includes ~15 different projects funded to date.  Also managed two DARPA projects on UV emitters.
  • Program Manager for the “National Laboratory Center for Solid-State Lighting R&D” (funded by the DOE Office of Energy Efficiency and Renewable Energy, 2006-2008).  Sandia had 5 projects funded under this short-lived program.

Report co-author, and LED Science Panel Co-Chair, for BES Workshop “Basic Research Needs for Solid-State Lighting,” 2006.  (See http://www.sc.doe.gov/bes/reports/list.html.) Member, Committee on Nanophotonics Accessibility and Applicability, National Research Council, 2006 – 2007.  Co-author of report by the same name.  (See http://www.nap.edu.)

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Photo of Jeff Tsao
Jeff Tsao
Distinguished Member of Technical Staff at Sandia National Laboratories and Chief Scientist of the Energy Frontier Research Center for Solid-State Lighting Science Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Jeff Tsao was born in 1955 and raised in Los Angeles, CA.  He is a graduate of Los Alamitos High School, Stanford University (AB in Mathematics, MS in Electrical Engineering) and Harvard University (MS, PhD in Applied Physics).

Jeff is currently a Principal Member of Technical Staff at Sandia National Laboratories, where his work involves integrated science, technology and economic modeling in Solid-State Lighting and other areas.  He is also exploring network models of knowledge production – a new approach to the field of “evolutionary epistemology.”

During 2000-2001 Jeff served as Vice-President of R&D at E2O Communications, Inc., a U.S.-based pre-IPO fiber communications components company.  There, he built and led an R&D team to develop long-wavelength VCSEL technology for uncooled 1-10Gbps short and intermediate-reach applications.

During 1996-2000, he was Manager of the Chemical Process Science Department at Sandia National Laboratories.  The focus of that department was the science and technology of semiconductor fabrication, with a special emphasis on metal-organic chemical vapor deposition of compound semiconductors.  He has also served as Manager of Sandia’s Semiconductor Materials Department, where he was responsible for developing epitaxial materials and processes for novel microelectronic and photonic devices and systems.

In 1998, he took a half-year sabbatical at the Institute of Materials Research and Engineering (IMRE) in Singapore, where he developed and gave a series of twelve lectures on compound semiconductor epitaxy that surveyed the entire field from science and technology all the way to applications.

Jeff has authored or co-authored over 150 publications:  two of them (one on laser microchemical processing and another on relaxation of strained semiconductor thin films) are considered “citation classics”.  He is also author of the 1993 research monograph “Materials Fundamentals of Molecular Beam Epitaxy,” now a standard reference work, for which he won one of Martin-Marietta’s highest corporate awards.

He has been active in the Materials Research Society:  he has co-chaired two symposia, was general co-chair of the Spring 1995 meeting, served for several years on the program committee, and during 1998-2000 coordinated the graduate student awards.  He has also served at various times on the program committees of the American Vacuum Society (Electronic Materials and Processing Division), the Electronic Materials Conference, the Optical Society of America, SPIE, and the North American MBE Conference.  He is a Fellow of the American Physical Society and the American Association for the Advancement of Science.

As manager of the compound semiconductor materials effort at Sandia in the mid-1990’s, he championed new science-based approaches to epitaxial growth (e.g., in situ monitoring and process modeling/control), and catalyzed and oversaw many of Sandia’s technology partnerships in compound semiconductor materials.  He has had the privilege of hiring and/or mentoring a series of world-class “growers,” all of whom have gone on to outstanding careers as entrepreneurs, scientists, professors, or technologists.

Education and Training

B. S. in Mathematics, Stanford University, Stanford, CA, 1977

M. S. in Electrical Engineering, Stanford University, Stanford, CA, 1977

M. S. in Applied Physics, Harvard University, Cambridge, MA, 1981

Ph. D. in Applied Physics, Harvard University, Cambridge, MA, 1981

Research and Professional Experience

Sandia National Laboratories, Member of the Technical Staff (2001 – present)

E2O Communications, Inc., Vice-President of R&D (2000-2001)

Tecstar, Inc., Member of Technical Advisory Board (2000 – 2001)

Institute of Materials Research and Engineering, Singapore, Visiting Lecturer, (1989-1999)

Sandia National Laboratories, Manager, Semiconductor Materials/Process Depts (1991-2000)

Sandia National Laboratories, Member of the Technical Staff (1983 – 1991)

MIT-Lincoln Laboratory, Member of Technical Staff (1981 – 1983)

Tachisto Lasers, Inc., Consultant (1980 – 1981)

Selected Publications

“Critical Stresses for SixGe1-x Strained-Layer Plasticity,” J.Y. Tsao, B.W. Dodson, S.T. Picraux, D.M. Cornelison, Physical Review Letters, 59, 2455 (1987).

“Materials Fundamentals of Molecular Beam Epitaxy,” J.Y. Tsao (Academic Press, 1993).

“A Review of Reflection Mass Spectrometry during III-V MBE,” J.Y. Tsao, Computational Materials Science, 6, 140 (1996).

“AlGaAs OMVPE in a Rotating-Disk Reactor: The Anatomy of a VCSEL,” W.G. Breiland, M.E. Coltrin, J. R. Creighton, H.Q. Hou, H.K. Moffat, and J.Y. Tsao, Materials Science and Engineering Reports, R24, 241 (1999).

“The Case for a National Research Program on Semiconductor Lighting,” R. Haitz, F. Kish, J.Y. Tsao, and J.S. Nelson (white paper first presented publicly at the 1999 Optoelectronics Industry Development Association (OIDA) forum in Washington DC on October 6, 1999).

“Light-Emitting Diodes (LEDS) for General Illumination,” J.Y. Tsao, Ed., OIDA Technology Roadmap (Optoelectronics Industry Development Association, October, 2002).

“Solid-Sate Lighting: Lamp Targets and Implications for the Semiconductor Chip,” J.Y. Tsao, IEEE Circuits & Devices 20, 3, 28-37 (May/June 2004).

“Research Challenges to Ultra-Efficient Inorganic Solid-State Lighting,” J.M. Phillips, M.E. Coltrin, M.H. Crawford, A.J. Fischer, M.R. Krames, R. Mueller-Mach, G.O. Mueller, Y. Ohno, L.E.S. Rohwer, J.A. Simmons, J.Y. Tsao, Laser and Photonics Reviews 1, 307-333 (2007).

“Galileo’s Stream: A Framework for Technical Knowledge Production,” J.Y. Tsao, W.B. Gauster, K.W. Boyack, M.E. Coltrin, J.G. Turnley, Research Policy 37, 330-352 (2008).

“The World’s Appetite for Light: A Simple Empirical Expression Spanning Three Centuries and Six Continents,” J.Y. Tsao, P. Waide and H.D. Saunders, submitted to the Energy Journal (June 2008).

Synergistic Activities

Coordinator and Editor, Light-Emitting Diodes (LEDS) for General Illumination Technology Roadmap (Optoelectronics Industry Development Association, October, 2002).

Coordinator, BES Workshop on “Basic Research Needs for Solar Energy Utilization,” 2005.

Honorary Chair, China International Forum on Solid-State Lighting (2006).

Coordinator, BES Workshop on “Basic Research Needs for Solid-State Lighting,” 2006.

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Research Challenge PIs

Photo of Andy Armstrong
Andy Armstrong
P.I. for "Point Defects in InGaN: Microscopic Origin and Influence on Macroscopic Luminescence." Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Andy Armstrong is a Senior Member of the Technical Staff in the Semiconductor Material and Devices Sciences Department at Sandia National Laboratories in Albuquerque, NM. He received a Ph. D. (2006) in electrical and computer engineering from The Ohio State University. His doctoral work involved defect spectroscopy of III-Nitride films and devices, including GaN, AlGaN, and AlGaN/GaN superlattices and HEMTs. He joined Sandia National Laboratories in January, 2007 and is currently developing programs in defect spectroscopy of high Al mole fraction p-type AlGaN, GaN nanostructures and InGaN films. His Ph. D. dissertation work resulted in five journal publications on novel defect spectroscopy techniques in wide band gap GaN and AlGaN films and devices, including the development of techniques to study deep levels in semi-insulating films and superlattices.

Education and Training

B. S. in Physics, Ohio State University, Columbus, OH, 1999

M. S. in Electrical Engineering, Ohio State University, Columbus, OH, 2001

Ph. D. in Electrical and Computer Engineering, Ohio State University, Columbus, OH, 2006

Research and Professional Experience

Sandia National Laboratories, Member of the Technical Staff (2/2007 – present)

Selected Publications

Depletion-mode photoconductivity study of deep levels in GaN nanowires, A. Armstrong, G. T. Wang and A.A. Talin, submitted to Journal of Electronic Materials (2008).

Characterization of majority and minority carrier deep levels in p-type GaN:Mg grown by molecular beam epitaxy using deep level optical spectroscopy, A. Armstrong, J. Cauldill, A. Corrion, C. Poblenz, U.K. Mishra, J.S. Speck and S.A. Ringel, submitted to Journal of Applied Physics (2007).

Quantitative observation and discrimination of AlGaN- and GaN-related deep levels in AlGaN/GaN heterostructures using capacitance deep level optical spectroscopy, A. Armstrong, A. Chakraborty, J.S. Speck, S.P. DenBaars, U.K. Mishra and S.A. Ringel, Applied Physics Letters 89, 262116 (2006).

Impact of substrate temperature on the incorporation of carbon-related defects and mechanism for semi- insulating behavior in GaN grown by molecular beam epitaxy, A. Armstrong, C. Poblenz, D.S. Green, U.K. Mishra, J.S. Speck and S.A. Ringel, Applied Physics Letters 88, 082114 (2006).

Impact of deep levels on the electrical conductivity and luminescence of gallium nitride co-doped with carbon and silicon, A. Armstrong, A.R. Arehart, D. Green, U.K. Mishra, J.S. Speck and S.A. Ringel, Journal of Applied Physics 98, 053704 (2005).

A method to determine deep level profiles in highly compensated, wide band gap semiconductors, A. Armstrong, A.R. Arehart and S.A. Ringel, Journal of Applied Physics 97, 083529 (2005).

Impact of carbon on trap states in n-type GaN grown by metalorganic chemical vapor deposition, A. Armstrong, A.R. Arehart, B. Moran, S.P. DenBaars, U.K. Mishra, J.S. Speck and S.A. Ringel, Applied Physics Letters 84, 374 (2004).

Synergistic Activities

Principal Investigator for the Novel Defect Spectroscopy of InGaN Materials for Improved Green LEDs (funded by the DOE Office of Energy Efficiency and Renewable Energy), 2008-2010.

Principal Investigator for the research project Defects and failure in GaN Nanowires (funded by the Sandia National Laboratory, Office of Laboratory Directed Research and Development, 2008-2010.

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Igal Brener
Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Igal Breneris a Principal Member of Technical Staff in the Applied Photonic Microsystem Department at Sandia National Laboratories in Albuquerque, NM. He received a B.Sc. degree in Electrical Engineering (1983), B.A. in Physics (1983), and a Doctorate degree in Physics (1991), all from the Technion, Israel Institute of Technology. His doctoral dissertation, “Dephasing and decay processes of excitons in semiconductor quantum well structures” was carried out both at the university and at Bell Labs. He joined Sandia National Laboratories in 2004 and has worked on many projects involving ultrafast techniques, Terahertz science and devices, plasmonics and lab-on-a-chip projects. In 2008 he became Nanophotonics Thrust Leader at the Center for Integrated Nanotechnologies, a joint Sandia-Los Alamos DOE user facility. From 1991 until 1993 he was a postdoctoral researcher at Bell Labs, Holmdel NJ, working in ultrafast carrier dynamics in semiconductors and Terahertz imaging and science. In 1993 he became staff member at Bell Labs, Murray Hill, NJ, in the Optical Physics Research Department. He performed research in diverse areas such as ultrafast lasers and spectroscopy of semiconductors, terahertz phenomena, fiber optical communication, nonlinear lithium-niobate waveguide devices, gallium-nitride lasers and semiconductor heterostructures. During that period, he also advised a number of Ph.D. and master’s students from NJIT, Stanford, and Technion. He left Bell Labs in 2000, to join Tellium, Inc. where he worked in optical switching and was group leader for algorithm development for servo-control of MEMS mirrors. In 2002, he joined Amersham Biosciences/GE Healthcare to work in single molecule detection techniques for DNA sequencing, high-sensitivity assays for single-cell gene expression and quantitative microscopy for gene expression analysis. During the years 2000-2002 he also served on the advisory board of Spectralane, Santa Clara, CA, a company that was created to commercialize some of Dr. Brener’s inventions in nonlinear lithium-niobate devices. Before his research career, he worked as a VLSI engineer and team leader at National Semiconductor in their first 32-bit microprocessor development team. He holds 13 US Patents, and has authored over 120 journal and conference papers. He has participated in several conference committees for the Optical Society of America (OSA) and Institute of Electrical and Electronics Engineers (IEEE). He has been a member of the organizing committee for the nanophotonics session for the BIOS conference at Photonics West (SPIE). Dr. Brener is a fellow of the Optical Society of America and a member of the Institute of Electrical and Electronics Engineers, and the Optical Society of America.

Education and Training

B. A. in Physics, Technion, Haifa, Israel, 1983 B. Sc. In Electrical Engineering, Technion, Haifa, Israel, 1983 D. Sc. in Physics, Technion, Haifa, Israel, 1991

Research and Professional Experience

Center for Integrated Nanotechnologies, Nanophotonics Thrust Leader (2008-present) Sandia National Laboratories, Principal Member of the Technical Staff (2004-present) Amersham Biosciences/GE Healthcare, Senior Scientist (2003-2004) Tellium Inc., Senior Member of Technical (2000-2002) Bell Laboratories, Lucent Technologies & AT&T, Member of Technical Staff, (1993–2000) Bell Laboratories, Postdoctoral Member of Technical Staff (1991-1993) National Semiconductor, Senior Electronic Engineer in VLSI MOS and Head of NS32332 microprocessor testing group (1983-1987)

Selected Publications

“Thin-film sensing with planar terahertz metamaterials: sensitivity and limitations,” J.F. O’Hara, R. Singh, I. Brener, et al., Optics Express 16, 1786-1795 (2008). “Nano-lithographically fabricated titanium dioxide based visible frequency three dimensional gap photonic crystal,” G. Subramania, Y.J. Lee, I. Brener, et al., Optics Express 15, 13049-13057 (2007). “Design and nonlinear servo control of MEMS mirrors and their performance in a large port count optical switch,” P.B. Chu, I. Brener, C. Pu, S-S. Lee, J.I. Dadap, S. Park, K. Bergman, et al., Journal of microelectromechanical systems 14, 261 (2005). “Terahertz near-field imaging,” J.F. Federici, O. Mitrofanov, M. Lee, J.W.P. Hsu, I. Brener, R. Harel, J.D. Wynn, L.N. Pfeiffer and K.W. West, Physics in Medicine and Biology, 47, 3727 (2002). “Tunable coherent far infrared radiation emission from biased semiconductor microcavities,” R. Harel, I. Brener, L.N. Pfeiffer, K.W. West, J.M. Vandenberg, S.G. Chu and J. Wynn, Springer Series in Chemical Physics, 66, 212 (2001). “Coherent terahertz radiation from cavity polaritons in GaAs/AlGaAs microcavities,” R. Harel, I. Brener, L.N. Pfeiffer, K.W. West, J.M. Vandenberg, S.G. Chu and J.D. Wynn, Physica Status Solidi A, 178, 365, (2000). “Time resolved near field imaging and diffraction with sub-wavelength far-infrared dipole sources,” I. Brener, S. Hunsche, Y. Cai, M.C. Nuss, J. Wynn, J. Lopata and L. Pfeiffer, Springer Series in Chemical Physics, 63, 171 (1998). “ScAlMgO4: An oxide substrate for GaN epitaxy,” E.S. Hellman, C.D. Brandle, L.F. Schneemeyer, D. Wiesmann, I. Brener, T. Siegrist, G.W. Berkstresser, D.N.E. Buchanan and E.H. Hartford, MRS Internet Journal of Nitride Semiconductor Research, 1 (1996). “Gain spectra and stimulated emission in epitaxial (In,Al)GaN thin films,” D. Wiesmann, I. Brener, L. Pfeiffer, M.A. Khan and C.J. Sun, Applied Physics Letters, 69, 3384 (1996). “Coherent control of terahertz emission and carrier populations in semiconductor heterostructures,” I. Brener, P.C.M. Planken, M.C. Nuss, M.S.C. Luo, S.L. Chuang, L. Pfeiffer and D. E. Leaird, Journal of the Optical Society of America B (Optical Physics), 11, 2457 (1994). “Shallow quantum well excitons: 2D or 3D?,” I. Brener, W.H. Knox, K.W. Goossen and J.E. Cunningham, Physical Review Letters, 70, 319 (1993). “Terahertz emission in single quantum wells after coherent optical excitation of light hole and heavy hole excitons,” P.C.M. Planken, M.C. Nuss, I. Brener, K.W. Goossen, M.S.C. Luo, S.L. Chuang and L. Pfeiffer, Physical Review Letters, 69, 3800 (1992).

Synergistic Activities

Nanophotonics Thrust Leader and PI on multiple plasmonic and metamaterial based projects, Center for Integrated Nanotechnologies, 2008-present Group Leader, “Metamaterials Grand Challenge”, Sandia, 2009-2012 Principal investigator for the Sandia Laboratory Directed Research and Development project “Plasmonic based thin sensors”, 2008-2010.

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Mary Crawford
Thrust Leader and P.I. for "Competing Energy Conversion Routes in Light-Emitting InGaN." Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Mary Crawford is a Distinguished Member of Technical Staff in the Semiconductor Material and Device Sciences Department at Sandia National Laboratories in Albuquerque, NM. She received a B. A. degree in physics from Holy Cross College (1985) and Sc. M. (1987) and Ph.D. (1993) degrees in physics from Brown University.  Her doctoral work involved spectroscopic studies of excitonic effects and gain in ZnSe-based quantum wells and laser diodes.  This work, in collaboration with Purdue University, contributed to one of the earliest demonstrations of a room temperature blue laser diode.  She joined Sandia National Laboratories in October, 1993 and has worked on many projects involving optical spectroscopy of semiconductor materials and the development of optoelectronic devices.  Her early work at Sandia focused on the development of novel vertical cavity surface emitting lasers (VCSELs), including AlInGaP-based red VCSELs and an intracavity frequency doubled VCSEL with emission in the blue region.  In 1996, she began work on wide-bandgap nitride materials, with an emphasis on photoluminescence spectroscopy of InGaN and AlGaN alloys and the development of UV LEDs.

In 2000, Dr. Crawford embarked on a two-year entrepreneurial leave and worked as a Senior Scientist and Director of Research and Development at Uniroyal Optoelectronics in Tampa, FL.  There she was primarily involved in the epitaxial growth and characterization of UV, blue, and green LEDs based on InGaN quantum well structures and coordinated R&D to support new LED products. She returned to Sandia in 2002 and has continued research and development of nitride-based materials and optoelectronic devices.  Her most recent studies include AlInGaN-based quantum well structures for deep UV (< 340 nm) LEDs and laser diodes and spectroscopic studies of radiative and nonradiative processes in blue/green InGaN materials.  She has co-authored more than 90 publications and is the recipient of 3 patents.

Education and Training

B. A. in Physics, Holy Cross College, Worcester, MA, 1985

Sc. M. in Physics, Brown University, Providence, RI, 1987

Ph. D. in Physics, Brown University, Providence, RI, 1993

Research and Professional Experience

Sandia National Laboratories, Member of the Technical Staff (1994-2000, 2002-present)

Uniroyal Optoelectronics, Senior Device Scientist and Director of R&D (2000-2002)

Sandia National Laboratories, Postdoctoral Associate (1993-1994)

Selected Publications

“Research Challenges to Ultra-Efficient Inorganic Solid-State Lighting,” J.M. Phillips, M.E. Coltrin, M.H. Crawford, A.J. Fischer, M.R. Krames, R. Mueller-Mach, G.O. Mueller, Y. Ohno, L.E.S. Rohwer, J.A. Simmons and J.Y. Tsao, Lasers and Photonics Reviews, 1, 4, 307 (2007).

“Effect of Dislocation Density on Efficiency Droop in GaInN/GaN Light-Emitting Diodes,” M. F. Schubert, S. Chhajed, J.K. Kim, E.F. Schubert, D.D. Koleske, M.H. Crawford, S.R. Lee, A.J. Fischer, G. Thaler and M.A. Banas, Appl. Phys. Lett. 91, 231114 (2007).

“Nanocrystal-based Light Emitting Diodes Utilizing High-Efficiency Nonradiative Energy Transfer for Color Conversion,” M. Achermann, M.A. Petruska, D.D. Koleske, M.H. Crawford and V.I. Klimov, Nano Letters 6, 1396 (2006).

“Room-temperature direct current operation of 290 nm light-emitting diodes with milliwatt power levels,”  A.J. Fischer, A.A. Allerman, M.H. Crawford, K.H.A. Bogart, S.R. Lee, R.J. Kaplar, W.W. Chow, S.R. Kurtz, K.W. Fullmer and J.J. Figiel, Appl. Phys. Lett. 84, 3394 (2004).

“Design and performance of nitride-based UV LEDs,” M.H. Crawford, J. Han, W.W. Chow, M. A. Banas, J.J. Figiel, L. Zhang and R.J. Shul, Proc. SPIE. 3938, 13, (2000).

“Optical spectroscopy of InGaN epilayers in the low indium composition regime”, M.H. Crawford, J. Han, M.A. Banas, S.M. Myers, G.A. Petersen and J.J. Figiel,MRS Internet J. Nitride Semicond.  Res, 5, 1, W11.41 (2000).

“The band-gap bowing of Al{sub x}Ga{sub 1-x}N alloys,” S.R. Lee, A.F. Wright, M.H. Crawford, G.A. Petersen, J. Han, R. M. Biefeld, Appl. Phys. Lett.74, 3344 (1999).

“AlGaN/GaN quantum well ultraviolet light emitting diodes,” J. Han, M.H. Crawford, R.J. Shul, J.J. Figiel, M. Banas, L. Zhang, Y.K. song, H. Zhou, A.V. Nurmikko,Appl. Phys. Lett. 73, 1688 (1998).

“Threshold conditions for an ultraviolet wavelength GaN quantum-well laser,” W.W. Chow, M. H. Crawford, A. Girndt, S.W. Koch, IEEE Journal of Sel. Topics in Quantum Electron. 4, 514 (1998).

Patent: “Broadband visible light source based on AlInGaN light emitting diodes,” M.H. Crawford and J. S. Nelson, #6, 665,329 (Issued Dec 2003).

Synergistic Activities

Committee member, Conference on Lasers and Electro-optics, LEDs, Organic LEDs and Solid-State Lighting conference, 2007-2009.

Panel member, Basic Energy Sciences Workshop on Solid-State Lighting, 2006.

Principal investigator for the Sandia Laboratory Directed Research and Development project “Nanoengineering for Solid-State Lighting”, 2006-2009.

Co-Principal investigator for the DARPA-funded Semiconductor UV Optical Sources (SUVOS) and Semiconductor AlGaN Injection Laser (SAIL) programs, 2002-2008.

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Art Fischer
Thrust Leader and P.I. for "Strongly Coupled Exciton-Photon Systems." Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Art Fischer is a Principal Member of the Technical Staff in the Semiconductor Materials and Device Science Department at Sandia National Laboratories in Albuquerque, NM. His primary research interests include he design, fabrication and testing of advanced semiconductor-based photonic structures.  He received his Ph.D. in Physics at Oklahoma State University in 1998.  His thesis work involved the use of ultrafast laser spectroscopy to measure dephasing times of excitons in wide band gap bulk and quantum well semiconductors.

Dr. Fischer joined Sandia National Labs as a post doctoral candidate in 1998 working on novel vertical cavity coupled resonator lasers.   As a post doc, his research also led to the first demonstrated 1.3 micron vertical cavity surface emitting laser.  He was hired as a staff member at Sandia in 2000 where he began working on basic science of nitride related materials for solid state lighting applications.  In his work at Sandia he has investigated a number of novel device concepts including photonic crystal light emitting diodes (LEDs) and surface Plasmon LEDs.

Education and Training

B. A. in Physics, University of Chicago, Chicago, IL, 1992

Ph. D. in Physics, Oklahoma State University, Stillwater, OK, 1998

Research and Professional Experience

Sandia National Laboratories, Member of the Technical Staff (10/2000 – present)

Sandia National Laboratories, Post Doctoral Candidate (10/1998 – 10/2000)

Oklahoma State University, Graduate Research Assistant (8/1995 – 5/1998)

Non-Imaging Optics, Undergraduate Student Intern (Summer 1991)

University of Chicago, Undergraduate Research Fellow (8/1991 – 5/1998)

Selected Publications

“CdSe infiltrated TiO2 based onmidirectional photonic crystals for visible light control,” G. Subramania, Y. Lee, B.A. Hemandez-Sanchez, A.J. Fischer, T.S. Luk, I. Brener, P.G. Clem and T.J. Boyle, Photonics and Nanostructures – Fundamental and Applications 6, 12 (2008).

“Light-extraction enhancement of GaInN light-emitting diodes by graded-refractive-index indium tin oxide anti-reflection contact, ” J.K. Kim, S. Chhajed, M.F. Schubert, E.F. Schubert, A.J. Fischer, M.H. Crawford, J. Cho, H. Kim and C. Sone, Advanced Materials 20, 801 (2008).

“Research Challenges to Ultra-Efficient Inorganic Solid-State Lighting,” J.M. Phillips, M.E. Coltrin, M.H. Crawford, A.J. Fischer, M.R. Krames, R. Mueller-Mach, Y. Ohno, L.E.S. Rohwer, J.A. Simmons, J.Y. Tsao, Laser and Photonic Reviews 1, 307 (2007).

“Effect of dislocation density on efficiency droop in GaInN/GaN light-emitting diodes,” M.F. Schubert, S. Chhajed, J. K. Kim, E. F. Schubert, D.D. Koleske, M.H. Crawford, S.R. Lee, A.J. Fischer, G. Thaler, M.A. Banas, Appl. Phys. Lett. 91, 231114-1-3 (2007).

“Junction temperature in ultraviolet light-emitting diodes,” Y.G. Xi, T. Gessmann, J.Q. Xi, J.K. Kim, J.M. Shah, E.F. Schubert, A.J. Fischer, M.H. Crawford, K.H.A. Bogart, A.A. Allerman, Japan. J. of Appl. Phys. 44, 7260 (2005).

“Junction and carrier temperature measurements in deep-ultraviolet light-emitting diodes using three different methods,” Y. Xi, J.Q. Xi, T. Gessmann, J.M. Shah, J.K.Kim, E.F. Schubert, A.J. Fischer, M.H. Crawford, K.H.A. Bogart, A.A. Allerman, Appl. Phys. Lett. 86, 031907 (2005).

“Growth and design of deep-UV (240-290 nm) light emitting diodes using AlGaN alloys,” A.A. Allerman, M.H. Crawford, A.J. Fischer, K.H.A. Bogart, S.R. Lee, D.M. Follstaedt, P.P. Provencio, D.D. Koleske,  J. of Crystal Growth 272, 227 (2004).

“Mid-ultraviolet light-emitting diode detects dipicolinic acid,” Q.Y. Li, P.K. Dasgupta, H. Temkin, M.H. Crawford, A.J. Fischer, A.A. Allerman, K.H.A. Bogart, S.R. Lee, Appl. Spectroscopy 58, 1360 (2004).

“Electroreflectance studies of Stark shifts and polarization-induced electric fields in InGaN/GaN single quantum wells,” R.J. Kaplar, S.R. Kurtz, D.D. Koleske, A.J. Fischer, J. Appl. Phys. 95, 4905 (2004).

Synergistic Activities

Principal Investigator for the research project “Investigation of Surface Plasmon Mediated Emission from InGaN LEDs using Nano-patterned Metal Films” (funded by the DOE Office of Energy Efficiency and Renewable Energy), 2006-2008.

Principal investigator for the Sandia Laboratory Directed Research and Development project “Enhanced spontaneous emission rate in visible III-nitride LEDs using 3D photonic crystal cavities,” 2006-2009.

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Jim Martin
P.I. for "Nanodots: Nonlinear Luminescence Dynamics." Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Jim Martin is a Distinguished Member of the Technical Staff in the Nanomaterials Sciences Department at Sandia National Laboratories in Albuquerque, NM. Martin received his B.S. in Chemistry in 1976 from the University of Washington.  He received his Ph.D. in Physical Chemistry in 1981 at the University of Washington with Advisors Bruce Eichinger and J. Michael Schurr. His dissertation research was on the “Physical Properties of Polymer Networks,” which combined graph theoretical topological analysis with experimental work using quasielastic light scattering to understand the effect of chemical bonding on the statistical physics of network-forming polymers.

Martin joined Sandia National Laboratories in 1981, and has since conducted theoretical, experimental and simulation research in a number of areas, including: the dynamics of linear and branched polymers in semi-dilute solutions; the fractal aggregation of colloidal suspensions; the statics and dynamics of the sol-gel transition; the nonlinear dynamics of colloidal suspensions subjected to the competing effects of steady or oscillatory shear and ac electric fields; the effect of audio frequency multi-axial ac magnetic fields on the structure and dynamics of particle suspensions; the discovery and development of complex field-structured composites and the investigation of their unique physical properties, including magnetoresistance, piezoresistance, thermoresistance and magnetostriction; the development of these composites as extreme response chemical sensors, strain sensors and actuators; studies of the kinetics of spinodal decomposition in inverse micellar solutions; sintering studies of noble metal nanoparticle superlattices;  investigations into the strong collective magnetism of structured dipolar nanocomposites of superparamagnetic nanoparticles; discovery and explanation of the strong intrinsic mixing of magnetic particle suspensions subjected to vortex magnetic fields; discovery of the formation of vortex lattices in magnetic platelet suspensions subjected to harmonic biaxial magnetic fields; and investigations of the recombination dynamics and luminescence of quantum dots, nanophosphors and acceptor-donor phosphors.  This work has resulted in well over 4000 citations, and is presented in 120 journal articles and five patents.

Selected Publications

“Measuring the Absolute Quantum Efficiency of Luminescent Materials,” L. Shea-Rohwer, J.E. Martin, J. Lumin. 115, 77-90 (2005).

“Lifetime Determination of Materials that Exhibit a Stretched Exponential Luminescent Decay.” L. Shea-Rohwer and J.E. Martin, J. Lumin. 121, 573-587 (2006).

“Luminescence Decay of Broad-Band Emission from CdS Quantum Dots,” L.E. Shea-Rohwer and J.E. Martin, J. Lumin. 127, 499-507 (2007).

“A 1-D Model of the Luminescent Decay of ZnS Phosphors as a Function of Excitation Conditions,” J.E. Martin, L.E. Shea-Rohwer, J. Lumin. 128 (2008).

“Increasing the Quantum Yield of Broad-Band Emission from CdS Quantum Dots by Surface Modification,” L.E. Shea-Rohwer and J.E. Martin, submitted to J. Electrochem Soc.

“Solvo-Thermal Synthesis of YAG:Ce Nanoparticle Dispersions,” M.D. Nyman, L.E. Shea-Rohwer, J.E. Martin and P. Provencio, submitted to Chem. Mat.

“Photoluminescence from Nanosize Gold Clusters,” J.P Wilcoxon J.E. Martin, D. Kelley, Wiedenman, F. Parsapour, J. Chem. Phys. 108, 9137 (1998).

“Optical Properties of Gold and Silver Nanoclusters Investigated by Liquid Chromatography,”  J.P. Wilcoxon J.E. Martin, P. Provencio, J. Chem. Phys. 115, 998-1008 (2001).

“Superlattices of Platinum and Palladium Nanoparticles” J.E. Martin J.P Wilcoxon, J. Odinek, P. Provencio, J. Phys. Chem. B. 106, 971-978 (2002).

“Sintering of Gold and Platinum Nanoclusters,” J.E. Martin J. Odinek J.P. Wilcoxon, R.A. Anderson, P. Provencio, J. Phys. Chem. B 107, 430-434 (2002).

“Control of Interparticle Spacing in Superlattices of Au Nanoparticles,” J.E. Martin, J. Wilcoxon, J. Odinek, P. Provencio, J. Phys. Chem. B. 104, 9475-9486 (2000).

Synergistic Activities

Co-investigator on the project: “Development of White LEDs using Nanophosphor/InP Blends,” (FY2006-2007, DOE/EERE National Energy Technology Lab)

Co-investigator on the project Nanocrystals-Polymer Composites for High Luminous Efficiency LEDs,” (FY 2004, Laboratory-Directed Research and Development Program)

Served on the Editorial Board of the Journal of Chemical Physics.

Served on the Los Alamos Neutron Scattering Center Advisory Committee.

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George Wang
Thrust Leader and P.I. for "Nanowires: Synthesis and Properties of Radial Heterostructures." Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

George Wang is a Principal Member of the Technical Staff in the Advanced Materials Sciences Department at Sandia National Laboratories.  Dr. Wang received his B.S. degree in Chemical Engineering, with Highest Honors, from the University of Texas at Austin in 1997, and M.S. and Ph.D. degrees in Chemical Engineering from Stanford University in 1999 and 2002, respectively, where he was awarded a National Science Foundation Graduate Fellowship and the David Sen-Lin Lee Fellowship.  His thesis work at Stanford focused on the functionalization of semiconductor surfaces using novel organic reactions under ultra-high vacuum.

At Sandia, Dr. Wang’s primary research efforts has focused on the synthesis, characterization, and applications of III-nitride nanowires grown by metal-organic chemical vapor deposition (MOCVD).  In addition, he has led efforts at Sandia in the 3D growth of high quality GaN using novel nanostructuring and selective growth techniques.  Dr. Wang has also investigated parasitic chemistry and Mg doping issues in AlGaInN MOCVD using a combination of insitu experimental techniques and density functional theory calculations.  Currently, Dr. Wang is a Thrust Leader investigating energy conversion processes in low-dimensional structures in the recently awarded 5-year, $18M Solid State Lighting Science Energy Frontier Research Center at Sandia, funded by DOE Basic Energy Sciences.

Recently, Dr. Wang has been responsible for the design, purchase, and start-up of a custom, state-of-the-art $3.5M nanofabrication and characterization system, the Advanced Nanotechnology Tool (ANT).  This world-class system, which came online in 2007 at Sandia’s new MESA facility, significantly bolsters Sandia’s nanoresearch capabilities.

Since 1999, Dr. Wang has authored or co-authored 34 journal publications, which have received over 600 citations, and 2 patents. His work has also received attention in Compound Semiconductor magazine, New Scientist magazine, The Guardian newspaper, Chemical and Engineering News magazine, and has been featured on the covers of Advanced Materials, Nanotechnology, and The Journal of Physical Chemistry B.

Education and Training

Ph. D. in Chemical Engineering, Stanford University, Stanford, CA, 2002

M. S. in Chemical Engineering, Stanford University, Stanford, CA, 1999

B. S. in Chemical Engineering, Highest Honors, The University of Texas at Austin, TX, 1997

Research and Professional Experience

Sandia National Laboratories, Member of the Technical Staff (9/2002 – present)

Stanford University, Graduate Research Assistant, Teaching Assistant (5/1998 – 9/2002)

Motorola, Austin, TX, Yield Engineer/Intern (Summer 1997)

Exxon Co. USA, New Orleans, LA, Reservoir Engineer (Summer 1996)

Selected Publications

“Spatial Distribution of Defect Luminescence in GaN Nanowires,” Q. M. Li, G. T. Wang, Nano Lett., 10, 1554 (2010).

“GaN nanowire surface state observed using deep level optical spectroscopy,” A. Armstrong, Q. Li, Y. Lin, A. A. Talin, G. T. Wang, Appl. Phys. Lett., 96,  (2010).

“Dislocation density reduction in GaN by dislocation filtering through a self-assembled monolayer of silica microspheres,” Q. Li, J. J. Figiel, G. T. Wang, Appl. Phys. Lett., 94,  (2009).

“Nanowire-templated lateral epitaxial growth of low-dislocation density nonpolar a-plane GaN on r-plane sapphire,” Q. Li, Y. Lin, J. R. Creighton, J. J. Figiel, G. T. Wang, Adv. Mat., 21, 2416 (2009). (cover article)

“Elastic moduli of faceted aluminum nitride nanotubes measured by contact resonance atomic force microscopy,” G. Stan, C. V. Ciobanu, T. P. Thayer, G. T. Wang, J. R. Creighton, K. P. Purushotham, L. A. Bendersky, R. F. Cook, Nanotechnology, 20,  (2009). (cover article)

“Photoluminescence, Thermal Transport, and Breakdown in Joule-Heated GaN Nanowires,” T. Westover, R. Jones, J. Y. Huang, G. T. Wang, E. Lai, A. A. Talin, Nano Lett., 9, 257 (2009).

“Three-Dimensional Visualization of Surface Defects in Core-Shell Nanowires,” I. Arslan, A. A. Talin, G. T. Wang, Journal of Physical Chemistry C, 112, 11093 (2008).

“The Role of Collisions in the Aligned Growth of Vertical Nanowires,” Q. Li, G. T. Wang, J. Crys. Growth, 310, 3706 (2008).

“Improvement in Aligned GaN Nanowire Growth using Submonolayer Ni Catalyst Films,” Q. Li, G. T. Wang, Appl. Phys. Lett., 93, 043119 (2008).

“Highly aligned, template-free growth and characterization of vertical GaN nanowires on sapphire by metal-organic chemical vapour deposition,” G. T. Wang, A. A. Talin, D. J. Werder, J. R. Creighton, E. Lai, R. J. Anderson, I. Arslan, Nanotechnology, 17, 5773 (2006).

“Complex formation between magnesocene (MgCp2) and NH3: Implications for p-type doping of group III nitrides and the Mg memory effect,” G. T. Wang, J. R. Creighton, J Phys Chem A, 108, 4873 (2004). (cover article)

Patents

Creighton, J.R. and G.T. Wang, “Method for improving Mg doping during group-III nitride MOCVD” U.S. Patent 7,449,404 (2008)

G.T. Wang, Q. Li, J.R. Creighton, “Nanowire-templated lateral epitaxial growth of non-polar group III Nitrides” U.S. Patent 7,670,933 B1 (2010)

Synergistic Activities

Thrust Leader, $18M DOE BES Energy Frontier Research Center for Solid State Lighting at Sandia National Laboratories (2009-2014).

Principal Investigator for the research project “The Physics of 1D and 2D Electron Gases in III-Nitride Heterostructure NWs” (funded by the Sandia’s LDRD program), 2006-2009.

Principal Investigator for the research project “Low Dislocation GaN via Defect-Filtering, Self-Assembled SiO2-Sphere Layers” (funded by the Sandia’s LDRD program), 2007-2009.

Co-investigatoron the projects: “Greater-Than 50% Efficient Photovoltaic Solar Cells”, 2009-2011, “Impact of Defects on the Electrical Transport, Optical Properties and Failure Mechanisms of GaN Nanowires”, 2007-2010, and “A Discovery Platform for Nanowire Electronics and Photonics,” 2005-2008 (previous three funded by the Sandia’s LDRD program), “Quantum Electronic Phenomena and Structures,” 2005-continuing, (funded by DOE BES),

Principal Investigator for the research project “Nanowire Templated Lateral Epitaxial Growth of Low Dislocation Density GaN” (funded by the DOE Office of Energy Efficiency and Renewable Energy), 2006-2008.

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Research Staff (Sandia National Laboratories)

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Bob Biefeld
Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center
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Weng Chow
Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Weng Chow received the Ph.D. degree in physics from the University of Arizona. He was an Associate Professor of Physics and Astronomy at the University of New Mexico before joining Sandia National Laboratories, where he is a Distinguished Member of the Technical Staff. Weng Chow’s primary research interest is in the application of microscopic theory to optoelectronic device development. Some of this work is described in two texts, Semiconductor-Laser Physics and Semiconductor-Laser Fundamentals: Physics of the Gain Materials. His other interests include laser gyros, phased arrays, coupled lasers, quantum optics and optical ignition of pyrotechnics. Dr. Chow is an Adjunct Professor of Optical Sciences at the University of Arizona, Research Professor at Texas A&M University, and Honorary Professor of Physics at Cardiff University, Wales. He is a fellow of the Optical Society of America, and received the 1998 Dept of Energy, Basic Energy Science/Material Science Award and a 2003 Alexander von Humboldt Forschungspreis.

Education and Training

Colorado State University (BS Physics, 1968)

University of Arizona (MS Physics,1974; Ph.D. Physics,1975)

Max-Planck Institute, Gottingen  (Post-doc, 1975-1977)

Research and Professional Experience

Sandia National Labs. (Distinguished Member of the Technical Staff, 1988-present)

Texas A&M University (Research Professor, 2006-present)

University of Arizona (Adjunct Research Professor of Optical Sciences, 1992-present)

University of Wales, Cardiff  (Honorary Professor of Physics, 2000-present)

Hughes Aircraft Company (Senior Staff Engineer, 1986-1988)

University of New Mexico (Assistant Professor, 1980-1983; Associate Professor, 1983-1986)

University of Arizona (Research Associate, 1978-1980)

Max-Planck Institute, Garching (Scientific Staff, 1977)

Consultant (Ferranti 1982-1983, International Laser Systems 1983-1984, Los Alamos National Labs. 1984-1986 Kirk-Mayer, Inc. 1984-1986, Air Force Weapons Labs.            IPA 1984-1986)

Selected Publications

Semiconductor Laser Physics, W.W. Chow, S.W. Koch and M. Sargent, III, New York: Springer-Verlag (1994).

Semiconductor-Laser Fundamentals: Physics of the Gain Materials, W.W. Chow and S.W. Koch, New York: Springer-Verlag (1999).

“Theory of emission from an active photonic lattice,” W.W. Chow, Phys. Rev. A. 73, 013821 (2006).

“Laser gain properties of AlGaN quantum wells,” W.W. Chow and M. Kneissl, J. Appl. Phys. 98, 114502 (2005).

“Influence of radiative coupling on coherent Rabi intersubband oscillations in multiple quantum wells,” I. Waldmueller, W.W. Chow and A. Knorr, Phys. Rev. B. 73, 035433 (2006).

“Anomaly in the excitation dependence of the optical gain of semiconductor quantum dots,” M. Lorke, W.W. Chow, T.R. Nielsen, J. Seebeck, P. Gartner and F. Jahnke, Phys. Rev. B 74, 035334 (2006).

“Self-induced chaos in a single-mode inversionless laser,” S. Wieczorek and W.W. Chow, Phys. Rev. Lett. 97, 113903/1-4 (2006).

“Circumventing the Manley-Rowe quantum efficiency limit in an optically pumped terahertz quantum-cascade amplifier,” I. Waldmueller, M.C. Wanke, W.W. Chow,
Phys. Rev. Lett. 99, 117401/1-4 (2007).

“Influence of quantum-well-barrier composition on gain and threshold current in AlGaN lasers,” W.W. Chow, M. Kneissl, J.E. Northrup and N. Johnson, Appl. Phys. Lett. 90 101116, (2007).

“Many-body theory of quantum coherence in semiconductor quantum dots,” W.W. Chow, S. Michael and H.C. Schneider, Journ. Modern Optics, 54, 2413-2424 (2007).

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Dan Koleske
Principal Member of the Technical Staff Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Dan Koleske is a Principal Member of the Technical Staff in the Advanced Materials Sciences Department at Sandia National Laboratories in Albuquerque, NM. His primary research interests are the growth of the group-III nitrides using metalorganic chemical vapor deposition.

In 1992, Dr. Koleske received his Ph.D. in physical chemistry at the University of Chicago. As a graduate student, he investigated oxidation on stepped Ni surfaces and surface vibration properties using both helium atom scattering and molecular dynamics techniques.

In Jan. of 1992, Dr. Koleske became a post-doctoral researcher with Dr. Stephen M. Gates at IBM T. J. Watson Research Center in Yorktown Heights, NY. At IBM, he used low energy ion scattering to measure surface kinetic reaction rates for developing atomic layer epitaxy for group IV semiconductors. Most significantly, these studies demonstrated direct surface abstraction between gas phase H and adsorbed H produced H2 via an Eley-Rideal mechanism. Halogen surface abstraction by atomic H was found to be less efficient, implying a “hot” precursor mechanism and not an Eley-Rideal mechanism was operative.

In November of 1993, Dr. Koleske was awarded a National Research Council (NRC)/ Naval Research Laboratory (NRL) Research Associateship. During this associateship he worked with Dr. Richard J. Colton in the Chemistry Division at NRL to develop scanning force microscopy techniques to chemically differentiate regions on a surface using adhesion, friction and contact potential contrast mechanisms. Using the force curve mapping technique, Dr. Koleske developed methods to distinguish chemical and mechanical contributions to nanometer-scale adhesion.

In October of 1995, Dr. Koleske became a staff member in the Thin Film Deposition Section (Code 6861) at the Naval Research Laboratory. Here, he investigated the MOCVD growth of group-III nitride semiconductors, working to optimize growth and investigate growth details. In 1998, he developed a kinetic model to explain GaN growth which is currently used by many groups to select initial growth conditions. Dr. Koleske has also thoroughly investigated GaN decomposition kinetics, resulting in a unified chemical mechanisms explaining nearly 30 years of work on this topic.

In June of 2001, Dr. Koleske joined Sandia National Laboratories. At Sandia, Dr. Koleske has continued his research on MOCVD growth of group-III nitride semiconductors, specifically, research on InGaN growth that has applications to improving solid state lighting. He has developed growth methodology that enhances the 3D growth mode and delays the 2D coalescence of GaN films on sapphire. This research led to improved light output of 380 nm LEDs by a factor of 15 compared to previous LEDs fabricated at Sandia. Dr. Koleske has researched on GaN nucleation layer evolution, which is critical to establishing the early stages of growth in GaN heteroepitaxy. Currently, he is researching indium incorporation and correlations between InGaN morphology and luminescence intensity.

Dr. Koleske has been a member of the Executive Committee for Electronic Materials and Processing Division of the AVS Science and Technology Society and is currently chair of the New Mexico AVS Science and Technology Society. He has authored or co-authored over 150 publications, has 2 patents, and has been cited in the literature > 2200 times.

Education and Training

B. S. in Chemistry, University of Wisconsin, Madison, WI, 1984

Ph. D. in Physical Chemistry, University of Chicago, Chicago, IL, 1992

Research and Professional Experience

Sandia National Laboratories, Member of the Technical Staff (5/2001 – present)

Naval Research Laboratory, Staff Member (8/1995 – 5/2001)

Naval Research Laboratory, Post Doc (11/1993 – 8/1995)

IBM T.J. Watson Research Center, Post Doc (1/1992 – 11/1993)

Selected Publications

“Growth model for GaN with comparison to structural, optical, and electrical properties,” D.D. Koleske, A.E. Wickenden, R.L. Henry, W.J. DeSisto and R.J. Gorman, Journal of Applied Physics 84, 1998 (1998).

“Enhanced GaN decomposition in H2 near atmospheric pressures,” D.D. Koleske, A.E. Wickenden, R.L. Henry, M.E. Twigg, J.C. Culbertson and R.J. Gorman, Applied Physics Letters 73, 2018 (1998).

“GaN decomposition in H2 and N2 at MOVPE temperatures and pressures,” D.D. Koleske, A.E. Wickenden, R.L. Henry, J.C. Culbertson and M.E. Twigg, Journal of Crystal Growth 223, 446-483 (2001).

“Improved brightness of 380 nm GaN light emitting diodes through intentional delay of the nucleation island coalescence,” D.D. Koleske, A.J. Fischer, A.A. Allerman, C.C. Mitchell, K.C. Cross, S.R. Kurtz, J.J. Figiel, K.W. Fullmer and W.G. Breiland, App. Phys. Lett. 81, 1940 (2002).

“In-situ measurements of GaN nucleation layer decomposition,” D.D. Koleske, M.E. Coltrin, A.A. Allerman, K.C. Cross, C.C. Mitchell and J.J. Figiel, Appl. Phys. Lett. 82, 1170 (2003).

“Understanding GaN Nucleation Layer Evolution on Sapphire,” D.D. Koleske, M.E. Coltrin, K.C. Cross, C.C. Mitchell and A.A. Allerman, J. Cryst. Growth, 273, 86 (2004).

“Using optical reflectance to measure GaN nucleation layer decomposition layer kinetics,” D.D. Koleske, M.E. Coltrin and M.J. Russell, J. Cryst. Growth, 279, 37 (2005).

Synergistic Activities

Principal Investigator for the research projects: “Novel ScGaN and YGaN Alloys for High-Efficiency Light Emitters” and “Nanostructural Engineering of Nitride Nucleation Layers for GaN Substrate Dislocation Reduction” (funded by the DOE Office of Energy Efficiency and Renewable Energy), 2006-2008.

Co-investigator on the projects: “Improved InGaN Epitaxy Yield by Precise Temperature Measurement”, “Ultrahigh-Efficiency Microcavity Photonic Crystal LEDs”, “Innovative Strain Engineered InGaN Materials of High-Efficiency Green Light Emission”, “Improved InGaN Epitaxial Quality by Optimizing Growth Chemistry”, and “Investigation of Surface Plasmon Mediated Emission from InGaN LEDs Using Nano-Patterned Films” (funded by the DOE Office of Energy Efficiency and Renewable Energy).

Organized Topical Conference on the “Science of Semiconductor White Light” at the AVS 51st and 52nd International Symposium in 2004 and 2005.

Invited talk “Improving Epitaxial Growth for LEDs” at the DOE sponsored “Transformations in Lighting 2008 SSL R&D Workshop” in Atlanta, GA in January 2008.

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Francois Leonard
Principal Member of the Technical Staff Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

François Léonard is a Principal Member of the Technical Staff in the Materials Physics Department at Sandia National Laboratories in Livermore, CA. His primary research interests are in theory and modeling of electronic transport in nanostructures.

Léonard received his Ph.D. in Physics at the University of Toronto, Canada in 1998. He spent two years as a postdoctoral fellow at the IBM T.J. Watson Research Center in Yorktown Heights, NY, where he developed the first theoretical and modeling approaches for electronic transport in carbon nanotube devices. Léonard joined Sandia National Laboratories in 2000, and initiated a program in electronic transport in nanostructures, first in theory and modeling and then adding an experimental component.

In his career, Dr. Léonard has advanced a detailed understanding of electronic transport in carbon nanotubes, nanowires and single molecules. For example, his early work on carbon nanotubes demonstrated that poor electrostatic screening in nanoscale materials affects profoundly the properties of carbon nanotube p-n junctions, Schottky contacts, and field-effect transistors. Recently, he has applied similar concepts to study the properties of III-V nanowires, discovering for instance that space-charge-limited transport is unusually strong in these materials.

Dr. Léonard has authored or co-authored over 40 journal publications, 60 conference presentations (including several invited talks), and a textbook entitled The Physics of Carbon Nanotube Devices, published by William-Andrew (2008).

Education and Training

Bachelor of Science in Physics, McGill University, 1994

Masters of Science in Physics, University of Toronto, 1995

Philosophical Doctorate, University of Toronto, 1998

Research and Professional Experience

Technical Staff, Sandia, CA, 2001-current

Limited Term Employee, Sandia, CA, 2000-2001

Postdoc, IBM T.J. Watson Research Center, 1998-2000

Selected Publications

“Unusually strong space-charge-limited current in thin wires,” A.A. Talin, F. Léonard, B. Swartzentruber, X. Wang and S. Hersee, Phys. Rev. Lett., 101, 076802 (2008).

“Size-dependent effects on electrical contacts to nanotubes and nanowires,” F. Léonard and A.A. Talin, Phys. Rev. Lett. 97, 026804 (2006).

“Energy conversion efficiency in nanotube opto-electronics,” D.A. Stewart and F. Léonard, Nanoletters 5, 219 (2005).

“Photocurrents in nanotube junctions,” D.A. Stewart and F. Léonard, Phys. Rev. Lett. 93, 107401 (2004).

“Negative differential resistance in nanotube devices,” F. Léonard and J. Tersoff, Phys. Rev. Lett. 85, 4767 (2000).

“Role of Fermi-level pinning in nanotube Schottky diodes,” F. Léonard and J. Tersoff, Phys. Rev. Lett. 84, 4693 (2000).

“Novel length scales in nanotube devices,” F. Léonard and J. Tersoff, Phys. Rev. Lett. 83, 5174 (1999).

Synergistic Activities

Panel member, and document writer for the BES Workshop on “Basic Research Needs for Solid-State Lighting,” 2006.

Principal Investigator for the project “Dynamics and Structure of Interfaces and Dislocations” (funded by the DOE Office of Science, Basic Energy Sciences), 2001-current.

Principal Investigator for the project “Controlled Fabrication of Nanowire Sensors” (funded by the Laboratory Directed Research and Development program at Sandia), 2004-2007.

Investigator for the project “Core/shell nanowires”, (funded by the Laboratory Directed Research and Development program at Sandia), 2007-current.

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Willie Luk
Principal Member of the Technical Staff Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Willie Luk is a Principal Member of Technical Staff in the Photonic Microsystems Technologies Department at Sandia National Laboratories in Albuquerque, New Mexico.  His primary research interests are photonic crystals, plasmonics, phononics and metamaterials.

Dr. Luk had spent 12 years in x-ray laser and coherent XUV and VUV radiation generation at the University of Illinois at Chicago under Prof. Rhodes.  The first project he worked on was high power short pulse propagation phenomena in atmosphere after a five span at the University of Wyoming.  Three years ago, he joined the photonic crystal group and worked on thermo-photovoltaic projects using photonic crystals.

Currently, he is working on using photonic crystals and photonic density of states control to enhance radiative yield of quantum emitters with the intent of reaching the strong coupling limit.  In addition, he is working on phononic crystal which is the acoustic analog of photonic crystal and metamaterials.

Dr. Luk was elected as Fellow of the Optical Society of America in 1993.  He has authored 55 refereed journal articles and 50 conference proceedings.

Education and Training

Ph.D. in Physics, State University of New York at Stony Brook, 1981.

B.Sc. in Physics, University of Hawaii at Manoa, 1975.

Research and Professional Experience

Sandia National Laboratories, Principal Member of Technical Staff. 1998-Present.

Assistant Professor of Physics, University of Wyoming, Laramie, Wyoming, 1993-1998.

Research Associate Professor of Physics, University of Illinois, Chicago, Illinois. 1984-1993.

Selected Publications

“CdSe infiltrated TiO2 based onmidirectional photonic crystals for visible light control,” G. Subramania, Y. Lee, B.A. Hemandez-Sanchez, A.J. Fischer, T.S. Luk, I. Brener, P.G. Clem, and T.J. Boyle, Photonics and Nanostructures – Fundamental and Applications, 6, 12 (2008).

“Emissivity measurements of 3D photonic crystals at high temperatures,” T.S. Luk, T. Mclellan, G. Subramania, J.C. Verley, I. El-Kady, Photonics and Nanostructures – Fundamental and Applications, 6, 81 (2008).

“Nano-lithograhically fabricated titanium dioxide based visible frequency three dimensional gap photonic crystal, ” G. Subramania, Y.J. Lee, I. Brener, T.S. Luk, P.G. Clem, Opt. Exp., 15, 13049 (2007).

“Observation of nonlinear optical phenomena in air and fused silica using 100GW, 1.54 mm source,” M.L. Naudeau, R.J. Law, T.S. Luk, T.R. Nelson, S. M. Cameron and J.V. Rudd, Optics Express, 14, 6194 (2006).

“Direct-write embedded waveguides and integrated optics in bulk glass by femtosecond laser pulses,” P. Yang, J.P. Guo, G.R. Burns and T.S. Luk, Opt. Eng., 44, 051104 (2005).

“High-power optical parametric chirped-pulse amplifier system with 1.54 mm signal and 1.064 mm pump,” J.V. Rudd, R.J. Law, T.S. Luk and S.M. Cameron, Opt. Lett., 30, 1974 (2005).

“Femtosecond laser-pulse-induced birefringence in optically isotropic glass,” P. Yang, G.R. Burns, J.P. Guo, T.S. Luk and G.A. Vawter, J. of Appl. Phys., 95, 5280 (2004).

“Propagation of self-focusing laser pulses in atmosphere: experiment versus numerical calculation,” T.A. Pitts, T.S. Luk, J.K. Gruetzner, T.R. Nelson, A. McPherson, S.M. Cameron and A.C. Bernstein, JOSA B: Optical Physics, 21, 2008 (2004).

Synergistic Activities

Principal investigator of “Efficient multi-exciton emission from quantum dots”, funded by Laboratory Directed Research and Development at Sandia National Laboratories.

Co-investigator on “Enhanced spontaneous emission rate in visible III-nitride LEDs using 3D photonic crystal cavities”, “Research on Micro-sized Acoustic Bandgap structures” and “Phonon Manipulation with Phononic Crystals”.

A scientist of Center of Integrated Nanotechology Center (CINT).

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Normand Modine
Principal Member of the Technical Staff Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Normand Modine is a Principal Member of the Technical Staff in the CINT Science Department at Sandia National Laboratories in Albuquerque, NM. He has sixteen years of experience in developing and applying computational techniques to understand the behavior of materials. His primary research interests are using computational techniques to research energy transfer processes, the dynamical behavior of defects, interfaces, and surfaces, and new methodologies for bridging length and time scales in nanoscale and nanostructured systems. Within the general area of energy transfer processes, Modine is particularly interested in the effects of system inhomogeneity on the redistribution of energy.  Examples include the processes by which excited electronic states captured by defects or electrons tunneling through a surface lose energy to local vibrational modes. Modine is also involved in developing predictive simulations of energy transfer between electronic and ionic degrees of freedom (for example, the rate of thermal equilibration between these subsystems) based on the Time-Dependent Density Functional Theory.  Modine has considerable experience in calculating the structure and energetics of defects and reconstructed surfaces, and he is working to extend these approaches to systems that are structurally disordered due to the effects of finite temperatures and/or alloying.  Furthermore, he would like to apply this experience to similar calculations for interfaces and/or surfaces with absorbed organic molecules. Finally, Modine is interested in developing new approaches to bridging length and time scales with emphasis on coupling quantum electronic structure to classical atomistics in order to accurately capture the interplay of local chemistry and collective phenomena.  Modine is one of the principal developers of the Socorro electronic structure software, a full featured, open source, massively parallel code for performing Kohn-Sham Density Functional Theory (DFT) calculations.  This code can be used to calculate relaxed structures, energetics, transition states, and molecular dynamics trajectories for systems involving thousands of atoms and provides a number of unusual advanced capabilities such as time-dependent density functional theory and an optimized effective potential implementation of the exact exchange approximation.

Education and Training

Ph.D. Physics, Harvard University, November 1996, GPA 3.89,  Advisor: Efthimios Kaxiras, Thesis: “Adaptive Basis Approaches to Quantum Spin and Electronic Systems Using Parallel Computers”

A.M. Physics, Harvard University, June 1992

B.S. Physics and B.S. Mathematics, Virginia Polytechnic Institute and State University, June 1990, GPA 3.99

Research and Professional Experience

Principal Member of the Technical Staff, Sandia National Laboratories, October 2003 – Present

Senior Member of the Technical Staff, Sandia National Laboratories, July 2000 -October 2003

Postdoctoral Researcher, Sandia National Laboratories, May 1998 – July 2000

Postdoctoral Researcher, Harvard University, November 1996 – April 1998

Postdoctoral Researcher, Rutgers University, October 1996 – November 1996

Research Staff, Harvard University, July 1996 – October 1996

Research Assistant, Harvard University, Fall 1993 – June 1996

Teaching Fellow, Harvard University, Fall 1994

Undergraduate Research Fellow, Oak Ridge National Laboratory, Summer 1989

Selected Publications

“Socorro electronic-structure software,” A.F. Wright, N.A. Modine, R.A. Lippert, R. Hatcher, A. Tackett, A.E. Mattsson, S.M. Foiles, M. P. Sears, R. P. Muller and S. J. Plimpton, Copyright Sandia Corporation (2002).

“Quantitative modeling of self-interstitial diffusion in silicon,” N.A. Modine, to Phys. Rev. B.

“Theory of the self-interstitial oxygen-interstitial complex in silicon,” N.A. Modine, to be submitted to Phys. Rev. B.

“Comparison of two methods for circumventing the coulomb divergence in supercell calculations for charged point defects,” A.F. Wright and N.A. Modine, Phys. Rev. B 74, 235209 (2006).

“The optimized effective potential with finite temperature,” R.A. Lippert, N.A. Modine and A.F. Wright, J. Phys.: Condens. Matter 18, 4295 (2006).

“Band structure of InGaAsN alloys and effects of pressure,” E.D. Jones, N.A. Modine, A.A. Allerman, S.R. Kurtz, A.F. Wright, S.T. Tozer and X. Wei, Phys. Rev. B 60, 4430 (1999).

“Photoluminescence-linewidth-derived reduced exciton mass for InGaAsN alloys,” E.D. Jones, A.A. Allerman, S.R. Kurtz, N.A. Modine, K.K. Bajaj, S.W. Tozer and X. Wei, Phys. Rev. B 62, 7144 (2000).

“Perturbation-induced compositional instability in epitaxial binary-alloy films,” S.R. Lee and N.A. Modine, Phys. Rev. Lett. 89, 205701 (2002).

“Laser gain and threshold properties of compressive-strained and lattice-matched GaInNAs/GaAs quantum wells,” W.W. Chow, E.D. Jones, N.A. Modine, A.A. Allerman and S.R. Kurtz, Appl. Phys. Lett. 75, 2891 (1999).

“Unusual evolution of the lowest unoccupied state in Ga(As0.5-yP0.5-yN2y),” L. Bellaiche, N.A. Modine and E.D. Jones, Phys. Rev. B 62, 15311 (2000).

Synergistic Activities

Center for Integrated Nanotechnologies Scientist (funded by the DOE Office of Basic Energy Science) (2007-Present).

Co-investigator for the Qualification Alternatives to the Sandia Pulses Reactor (QASPR) Project (funded by NNSA) (2005-Present).

Co-investigator for the “Enhanced Molecular Dynamics for Simulating Thermal and Charge Transport Phenomena in Metals and Semiconductors” project (funded by Sandia LDRD) (2007-present)

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Lauren Rohwer
Principal Member of the Technical Staff Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Lauren Rohwer is a Principal Member of the Technical Staff at Sandia National Laboratories in Albuquerque, NM. Her research interests include the synthesis and characterization of nanoscale luminescent materials with applications to solid-state lighting (SSL). Lauren received her Ph.D. in Materials Science from the University of California, San Diego in 1997.  At UCSD she pioneered the use of combustion synthesis for producing efficient, small particle size oxide phosphors. She joined Sandia National Laboratories in 1997, and began studying the low-voltage cathodoluminescence (CL) of display phosphors.  This work led to the development of a measurement standard for CL luminous efficiency of phosphor powders and films.  She partnered with GE Global Research to study the quantum splitting of Pr3+ ions in oxide hosts for mercury-free fluorescent lighting  Her interest in nanoscale luminescent materials began with studies of II-VI semiconductor quantum dots (QDs) for SSL, leading to the first demonstration of solid-state light sources based on encapsulated CdS QDs. She studied the photoluminescence decay dynamics of QDs and phosphors in the time and frequency domains.  Several interesting discoveries came from this work.  In CdS QDs, the surface ligands strongly affect the functional form of the decay; with trap states giving rise to broadband emission and a stretched exponential decay with long characteristic lifetimes.  The nonexponential decay dynamics of the complex donor-acceptor phosphor ZnS:Cu,Al are a strong function of the excitation conditions.  She co-developed a 1-D model of ZnS phosphors that explains some intriguing experimental observations such as a cross-over from stretched exponential to power law decay due to the development of spatial correlations between electrons and holes. She recently completed a successful program on the development of oxide nanophosphors for SSL.  This program identified three new Eu3+-doped red emitters for blue LED excitation; and achieved transparent nanoparticle dispersions of phosphors such as yellow-green-emitting YAG:Ce.  New luminescent phases of strontium vanadate were also discovered during the course of this program. Lauren served as Chair of the Luminescence and Display Materials Division of the Electrochemical Society.  She is co-editor of the Handbook of Luminescence Display Materials, and Devices, American Scientific Publishers.  She has authored or co-authored over thirty publications and one U.S. Patent.

Education and Training

B. S. in Physics, University of Massachusetts, Amherst, MA, 1990 M. S. in Materials Science & Engineering, Virginia Tech, Blacksburg, VA, 1993 Ph. D. in Materials Science, University of California, San Diego, La Jolla, CA, 1997

Research and Professional Experience

Sandia National Laboratories, Member of the Technical Staff (6/1998 – present) Sandia National Laboratories, Limited Term (4/1997 – 6/1998)

Selected Publications

“Solvothermal synthesis of YAG:Ce nanoparticle dispersions,” M.D. Nyman, L.E. Shea-Rohwer, J.E. Martin and P. Provencio, submitted to Chemistry of Materials (2008). “A 1D model of the photoluminescent decay of ZnS phosphors as function of excitation conditions,” J. E. Martin and L.E. Shea-Rohwer, J Lumin. 128, 9, 1407-20 (2008). “Increasing the quantum yield of broadband emission from CdS quantum dots by surface modification,” L.E. Shea-Rohwer, J. E. Martin, submitted to J. Electrochem. Soc. (2008). “Research challenges to ultra-efficient inorganic solid-state lighting,” J.M. Phillips, M.E. Coltrin, M.H. Crawford, A.J. Fischer, M.R. Krames, R. Mueller-Mach, Y. Ohno, L.E. Shea-Rohwer, J.A. Simmons and J.Y. Tsao, Laser & Photon. Rev. 1, 4, 307-33 (2007). “Luminescence decay of broadband emission from CdS quantum dots,” L.E. Shea-Rohwer and J. E. Martin, J. Lumin., 127, 2, 499 (2007). “Lifetime determination of materials that exhibit a stretched exponential luminescent decay,” J. E. Martin and L.E. Shea-Rohwer, J. Lumin., 121, 2, 573 (2006). “Measuring the absolute quantum efficiency of luminescent materials,” L.E. Shea-Rohwer and J. E. Martin, J. Lumin., 115, 3-4, 77 (2005). “Improving the efficiency of a blue-emitting phosphor by an energy transfer from Gd3+ to Ce3+,” E.J. Bosze, G.A. Hirata, L.E. Shea-Rohwer, and J. McKittrick, J. Lumin., 104, 1-2, 47 (2003). “Development of phosphors for LEDs,” L.E. Shea-Rohwer and A.M. Srivastava, Electrochemical Society Interface, 12,2, 36 (2003).

Synergistic Activities

Principal Investigator for the research project “Development of White LEDs Based on Nanophosphor-InP Blends” (funded by the DOE National Energy Technology Laboratory), 2006-2008. Principal Investigator for the research project “Nanocrystal-Polymer Composites for High Luminous Efficiency LEDs” (funded by Sandia’s Laboratory Directed Research & Development Program) 2003-2004. Co-investigator on the Solid-State Lighting Grand Challenge (funded by Sandia’s Laboratory Directed Research & Development Program) 2000-2003. Chair of the Luminescence and Display Materials Division of the Electrochemical Society, 2003-2005. Co-organizer of the 2nd International Symposium on Inorganic & Organic Luminescent Materials for Light-Emitting Diodes (Electrochemical Society 2003).

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Eric Shaner
P.I. for "Surface Plasmonic Intermediates to Exciton-Photon Interactions." Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Eric Shaneris a Senior Member of the Technical Staff in the Semiconductor Materials & Device Sciences Department at Sandia National Laboratories in Albuquerque, NM. His current research interests span terahertz to visible frequencies including a strong focus on plasmonic interactions with semiconductor materials. Shaner received his Ph.D. in Electrical Engineering from Princeton University in 2004.  He joined Sandia National Laboratories that same year as a post-doc, and was converted to staff in 2005.

Education and Training

B. S. in Physics, St. John Fisher College, 1997 Ph. D. in Electrical Engineering, Princeton University, Princeton, NJ 2004

Research and Professional Experience

Sandia National Laboratories, Member of the Technical Staff (2005 – present) Engineering Consultant to Orchid Bioscience, Princeton, NJ (5/1999-1/2003)

Selected Publications

“Electrically tunable extraordinary optical transmission gratings,” E.A. Shaner, J.G. Cederberg and D. Wasserman, Appl. Phys. Lett. 91, 181110 (2007). “Midinfrared doping-tunable extraordinary transmission from sub-wavelength Gratings,” D. Wasserman, E.A. Shaner and J.G. Cederberg, Appl. Phys. Lett. 90, 191102 (2007). “Enhanced responsivity in membrane isolated split-grating-gate plasmonic terahertz detectors,” E.A. Shaner, M.C. Wanke, A.D. Grine, S.K. Lyo, J.L. Reno and S.J. Allen, Appl. Phys. Lett. 90, 181127 (2007). “Multiple wavelength anisotropically polarized mid-infrared emission from InAs quantum dots,” D. Wasserman, C. Gmachl, S.A. Lyon and E.A. Shaner, Appl. Phys. Lett. 88, 191118 (2006). “A Far-Infrared Spectrometer-on-a-Chip using Plasmon Modes in a Quantum-Well Transistor,” E.A. Shaner, A.D. Grine, M.C. Wanke, M. Lee, J.L. Reno, S.J. Allen, IEEE Photonics Technology Letters 18, 18, 1925 (2006). “Single-quantum-well grating-gated terahertz plasmon detectors,” E.A. Shaner, M. Lee, M.C. Wanke, A.D. Grine, J.L. Reno and S.J. Allen, Appl. Phys. Lett. 87, 193507 (2005). E.A. Shaner and S.A. Lyon, “Picosecond time-resolved two-dimensional ballistic electron transport,” Phys. Rev. Lett.93, 037402 (2004).

Synergistic Activities

Principal Investigator for the project “InAs quantum dot emitters utilizing planar photonic crystal technology” (funded by the DOE Office of Energy Efficiency and Renewable Energy), 2006-2008.

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Ganesh Subramania
Member of the Technical Staff Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Ganesh Subramania is a Member of Technical Staff in Photonics Microsystem Technology department of Sandia National Laboratories in Albuquerque, NM. He received his Bachelor of Technology in Electrical Engineering (1992) from the Indian Institute of Technology , Chennai, India, and M.S  in Condensed Matter Physics (1994) and Ph.D in Electrical engineering and Applied Physics ( 2000) from Iowa State University.  His doctoral dissertation work involved the design, fabrication and characterization of visible frequency photonic crystals. This work  first demonstrated photonic crystal with photonic bandgap in the visible frequency which  was  fabricated  using  simultaneous self-assembly of  submicron polystyrene spheres  and nanoparticle titanium dioxide resulting in subsequent US patent award  2002.  He joined the Department of Material Science at MIT as postdoctoral associate in 2000 and worked on biocompatible photonic crystals.  He joined Sandia in 2001 as a post doctoral associate. His work involved fabricating GaAs / AlGaAs based 2D photonic crystal based high quality factor low mode volume nanocavities for enhanced non-linear effect and switching. During this period he also developed a multi-level electron beam lithography approach to  fabricate complete bandgap photonic crystals with sub-0.5 mm period for bandgaps in the near infrared to the visible frequency.  This resulted in the demonstration of the first titanium dioxide based logpile photonic crystal with bandgap near 500nm wavelength. As a staff member from 2004 he continued his work on developing novel photonic crystal structures and utilize their unique properties for active control and manipulation of light for energy efficiency light sources.

His current interest involves exploring light matter interaction inside nanostructured environments like photonic crystals and metamaterials  such as spontaneous emission control of  nano light sources (e.g. CdSe quantum dots and  GaN nanopost LEDs); weak and strong coupling; non-classical light generation.

Education and Training

B.Tech, Electrical and Electronics Engineering,   Indian Institute of Technology, Madras, India, 1992

M.S., Condensed Matter Physics, Iowa State University Ames, IA 1994

Ph.D., Co-major in Electrical Engineering and Applied Physics, Iowa State University Ames,  2000

Research and Professional Experience

Sandia National Laboratories, Albuquerque, NM,  Member of Technical Staff,  2004-present

Sandia National Laboratories, Albuquerque, NM,  Post doctoral associate, 2001-2004.

Massachusetts Institute of Technology,   Cambridge, MA  , Post doctoral associate, 2000-2001.

Selected Publications

“CdSe infiltrated TiO2 based omnidirectional photoniccrystals for visible light control,”  G. Subramania, Y.J. Lee, B.A. Hernandez-Sanchez, A.J. Fischer, T.S. Luk, I. Brener, P.G. Clem and T. Boyle, Photonics and Nanostructures: Fundamentals and Applications, 6, 12 (2008).

“Emissivity measurements of 3D photonic crystals at high temperatures,” T.S. Luk T. Mclellan, G. Subramania, J.C. Verley, I. El-Kady, Photonics and Nanostructures: Fundamentals and Applications, 6, 81 (2008).

“Nano-lithographically fabricated  titanium dioxide based visible frequency three dimensional gap photonic crystal,” G. Subramania, Y-J. Lee, I. Brener, T.S. Luk and P.G. Clem, Opt. Exp., 15, 13049 (2007).

“Planarization for three-dimensional photonic crystals and other multi-level nanoscale structures,” G. Subramania, Nanotechnology 18, 3, 035303 (2007).

“Complete three dimensional gap photonic crystals in the near infrared and visible wavelengths for sensing applications,” G. Subramania, Y.J. Lee, J.C. Verley, J.G. Fleming, I. El-Kady,  T.S. Luk, P.G. Clem, I. Brener,  SPIE proceedings 6322, 32204-32204 (2006).

“Fabrication of three-dimensional photonic crystal with alignment based on electron beam lithography,” G. Subramania and S.Y. Lin, Applied Physics Letters l.85, 21, 5037-9 (2004).

“Tuning the microcavity resonant wavelength in a two-dimensional photonic crystal by modifying the cavity geometry,” G. Subramania, S.Y. Lin, J.R. Wendt and J.M. Rivera, Applied Physics Letters, 83, 22, 4491-3 (2003).

“Structural characterization of thin film photonic crystals,” G. Subramania, K. Constant, R. Biswas, M.M. Sigalas and K.M. Ho, Physical Review B, 6323, 23, 5111 (2001).

“Optical photonic crystals fabricated from colloidal systems,”  G. Subramania, K.Constant, R. Biswas, M.M. Sigalas and K.M. Ho, Applied Physics Letters, 74, 26, 3933-3935 (1999).

“Fabrication of photonic bandgap materials using ceramic processing techniques,” K.Constant, G. Subramania, R. Biswas and K.M. Ho.  US Patent No. 6,339,030 (awarded on Jan 15 2002).

Synergistic Activities

Conference Chair for SPIE  “Active Photonic Crystal” conference 2007-present.

Co-PI for the Sandia Laboratory Directed Research and Development project, “Enhanced spontaneous emission rate in visible III-nitride LEDs using 3D photonic crystal cavities”, 2006-2009

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Jonathan Wierer
Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center
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Postdocs and Students

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Rohan Kekatpure
Post Doc Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center
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Sasha Neumann
Grad Student Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center
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Troy Ribaudo
Grad Student Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center
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Minah Seo
Post Doc Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center
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Prashanth Upadhya
Post Doc Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center
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Jeremy Wright
Grad Student Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center
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Public Outreach

Photo of Alyssa Christy
Alyssa Christy
Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Alyssa Christy is a member of the Partnerships Development and Business Intelligence department at Sandia National Laboratories. She received a M.A. (2009) in Rhetoric and Writing and a B.A. (2007) in English, with a minor in Business from the University of New Mexico. Alyssa joined the labs in 2009 and is currently involved in public outreach activities for the SSLS EFRC.

 

Education and Training

M.A. in Rhetoric and Writing, University of New Mexico, Albuquerque, NM, 2009

B.A. in English (suma cum laude), University of New Mexico, Albuquerque, NM, 2007

Research and Professional Experience

Sandia National Laboratories, Business Planner (11/2009 – present)

University of New Mexico, Part Time Instructor, Freshman Composition and Technical Writing (8/2009 – 12/2009)

University of New Mexico, Teaching Assistant, Freshman Composition (8/2007 – 5/2009)

Plunkett Research, Staff Writer (Summer 2007)

Freelance Editor (8/2007 – present)

Freelance Layout Designer (8/2008 – present)

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Rene Sells
Principal Member of Laboratory Staff Sandia National LaboratoriesSolid-State Lighting Science Energy Frontier Research Center

Rene Sells is a Principal Member of Laboratory Staff in the Partnerships Development and Business Intelligence Department at Sandia National Laboratories in Albuquerque, NM. She received her B.A. (1998) in Journalism and Mass Communication and M.B.A (2002) in Marketing Management from the University of New Mexico. Rene joined the labs in 2001 and is currently the business development lead within the partnerships group for basic science and energy related programs. She actively works with representatives from private companies, universities and government agencies who are interested in partnering with Sandia.

Education and Training

B.A. in Journalism and Mass Communications, University of New Mexico, Albuquerque, NM, 1998.

M.B.A. in Marketing Management, University of New Mexico, Albuquerque, NM, 2002.

Research and Professional Experience

Sandia National Laboratories, Member of Laboratory Staff (7/2002 – present)

Sandia National Laboratories, Business Development Intern (5/2001 – 7/2002)

Charter Companies, Marketing Specialist (8/1998 – 5/2001)

Daily Lobo Reporter, University of New Mexico (8/1997 – 5/1998)

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External Research Partners

Photo of Harry Atwater
Harry Atwater
Howard Hughes Professor and Professor of Applied Physics and Materials Science California Institute of Technology

Harry Atwater is currently Howard Hughes Professor and Professor of Applied Physics and Materials Science at the California Institute of Technology. Atwater received his S.B. (1981), S.M. (1983), and Ph.D. (1987) in Electrical Engineering from the Massachusetts Institute of Technology.

His research interests center around photovoltaics, nanophotonics, and photoelectrochemical devices for solar fuel production. He is a early pioneer in surface plasmon photonics; he gave the name to the field of plasmonics in 2001; developments in this field were recently featured in his article about plasmonics in the May 2007 of Scientific American.

Professor Atwater is founder and chief technical advisor for Aonex Corporation. He has consulted extensively for industry and government, and has actively served the materials community in various capacities, including Material Research Society Meeting Chair (1997), Materials Research Society President (2000), AVS Electronic Materials and Processing Division Chair (1999). In 2001 he served as a Gordon Conference Chair, and in 2008 he will serve as Chair for the Gordon Research Conference on Plasmonics. He currently serves as Director of Caltech’s Center for Science and Engineering of Materials (an NSF MRSEC; http://www.csem.caltech.edu), and is also Director of the Caltech Center for Sustainable Energy Research(http://www.ccser.caltech.edu). He serves on the Director’s Review Committee, Chemistry and Materials Science Division, Lawrence Livermore National Laboratory; and the Board of Trustees, Gordon Research Conferences. He has served on the Department of Energy, Office of Science, Division of Materials Sciences Visiting Committee; Stanford University Department of Materials Science and Engineering Visiting Committee; National Science Foundation Division of Materials Research Visiting Committee. Atwater is founder and chief technical advisor for Aonex Corporation. He is also an editorial board member for Surface Review and Letters.

Atwater has been honored by awards including the Joop Los Fellowship from the Dutch Society for Fundamental Research on Matter, 2005; A.T. & T. Foundation Award, 1990; NSF Presidential Young Investigator Award, 1989; IBM Faculty Development Award, 1989-1990; Member, Bohmische Physical Society, 1990; IBM Postdoctoral Fellowship, 1987.

Education and Training

Massachusetts Institute of Technology, Electrical Engineering, S.B. 1981

Massachusetts Institute of Technology, Electrical Engineering, S.M. 1983

Massachusetts Institute of Technology, Electrical Engineering, Ph.D.1987

Harvard University Postdoctoral Fellow 1988

Research and Professional Experience

Howard Hughes Professor and Professor of Applied Physics and Materials Science, California Institute of Technology (2001)

Gordon McKay Professor of Applied Physics, Harvard University (2002-2003)

Professor of Applied Physics and Materials Science, California Institute of Technology (1999-2001)

Associate Professor of Applied Physics, California Institute of Technology (1994-1999)

Assistant Professor of Applied Physics, California Institute of Technology (1988-1994)

IBM Postdoctoral Fellow, Harvard University (1987-88)

Graduate Assistant, Massachusetts Institute of Technology (1981-1987)

Selected Publications

“GaInP/GaAs dual junction solar cells on Ge/Si epitaxial templates,” M. J. Archer, D.C. Law, S. Mesropian, M. Haddad, C.M. Fetzer, A.C. Ackerman, C. Ladous, R.R. King and H.A. Atwater, Applied Physics Letters 92 (2008).

“Macroporous silicon as a model for silicon wire array solar cells,” J.R. Maiolo, H.A. Atwater and N.S. Lewis, Journal of Physical Chemistry C 112, 6194-6201 (2008).

“Improved electrical properties of wafer-bonded p-GaAs/n-InP interfaces with sulfide passivation,”.K. Nakayama, K. Tanabe and H.A. Atwater, Journal of Applied Physics 103 (2008).

“Quantitative determination of optical transmission through subwavelength slit arrays in Ag films: Role of surface wave interference and local coupling between adjacent slits,” D. Pacifici, H.J. Lezec, H.A. Atwater and J. Weiner, Physical Review B 77 (2008).

“Universal optical transmission features in periodic and quasiperiodic hole arrays,” D. Pacifici,  H.J. Lezec, L.A. Sweatlock, R.J. Walters and H.A. Atwater, Optics Express 16, 9222-9238 (2008).

“Optical cavity modes in gold shell colloids,” J.J. Penninkhof, L.A. Sweatlock, A. Moroz, H.A. Atwater,  A. van Blaaderen and A. Polman, Journal of Applied Physics 103 (2008).

“InGaN/GaN multi-quantum well and LED growth on wafer-bonded sapphire-on-polycrystalline AlN substrates by metalorganic chemical vapor deposition,” T. Pinnington, D.D. Koleske, J.M. Zahler, C. Ladous, Y.B. Park, M.H. Crawford, M. Banas, G. Thaler, M.J. Russell, S.M. Olson and H.A. Atwater, Journal of Crystal Growth 310, 2514-2519 (2008).

“A comparison between the behavior of nanorod array and planar Cd(Se, Te) photoelectrodes,” J.M. Spurgeon, H.A. Atwater and N.S. Lewis, Journal of Physical Chemistry C 112, 6186-6193 (2008).

“Repeated epitaxial growth and transfer of arrays of patterned, vertically aligned, crystalline Si wires from a single Si(111) substrate,” J.M. Spurgeon, K.E. Plass, B.M. Kayes, B.S. Brunschwig, H.A. Atwater and N.S. Lewis, Applied Physics Letters 93 (2008).

“Surface plasmon polariton modes in a single-crystal Au nanoresonator fabricated using focused-ion-beam milling,” E.J.R. Vesseur, R. de Waele, H.J. Lezec, H.A. Atwater, F.J.G. de Abajo and A. Polman., Applied Physics Letters 92 (2008).

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Steve Brueck
Director of the Center for High Technology Materials University of New Mexico

Steve Brueck is the director of the Center for High Technology Materials and is a professor of electrical and computer engineering and a professor of physics and astronomy at the University of New Mexico. As CHTM director, he manages research and education programs that cross optoelectronics, microelectronics and nanoscience. Optoelectronics, uniting optics and electronics, and is found in CHTM’s emphasis on semiconductor laser sources, optical modulators, detectors and optical fibers. Microelectronics applies semiconductor technology to the fabrication of electronic and optoelectronic devices for information and control applications. A clear necessity for advanced research is a nanoscale fabrication capability. His group has developed interferometric lithography with a demonstrated large-field 45 nm half-pitch capability for periodic structures and imaging interferometric lithography for arbitrary patterns to the same scales. He works closely with industry, particularly SEMATECH, in the development of immersion techniques. He is also site director of the UNM National Nanotechnology Infrastructure Network node, an NSF-funded nanotechnology user facility. He is also a former research staff member of MIT Lincoln Laboratories. He is a member of the American Physical Society, the Materials Research Society, and SPIE; a fellow of the Institute of Electrical and Electronics Engineers, a fellow of the Optical Society of America and a fellow of the American Association for the Advancement of Science. His expertise includes nano science/technology, materials, electronics, and physics. He has over 350 refereed publications, 200 invited talks, and 34 patents.

Education and Training

Columbia University, Electrical Engineering, B.S., 1965

Massachusetts Institute of Technology, Electrical Engineering, M.S., 1967

Massachusetts Institute of Technology, Electrical Engineering, PhD. 1971

Research and Professional Experience

Postdoctoral research associate, MIT Lincoln Laboratory (1971-1973)

Member Technical Staff, MIT Lincoln Laboratory (1973-1985)

Professor, Electrical Engineering and Physics, University of New Mexico (1985-2006)

Distinguished Professor, Electrical Engineering and Physics, UNM (2006-present)

Director, Center for High Technology Materials, University of New Mexico (1986-present)

Selected Professional Activities

Fellow of OSA, IEEE and AAAS

Chair, EIPBN, 2008

CLEO Steering Chair, 2001 – 2003

General co-chair CLEO, 2000

Program co-chair CLEO, 1998

Founding Editor, IEEE Journal of Selected Topics in Quantum Electronics, 1995

Editor, IEEE Journal of Quantum Electronics, 1989-1994

Associate Editor, Optics Letters, 1984-1986

Honors, Awards, and Society Offices

IEEE LEOS Board of Governors, 1989-1991

Outstanding Faculty Researcher, College of Engineering, University of New Mexico, 1991

IEEE Third Millennium Medal

Distinguished Professor, University of New Mexico

Norbert Kreidl Memorial Lecturer, New Mexico Materials Association, 2007

Selected Publications

A. Raub, D. Li, A. Frauenglass and S. R. J. Brueck, Fabrication of 22-nm Half-Pitch Silicon Lines by Single-Exposure Self-Aligned Spatial-Frequency Doubling, Jour. Vac. Sci. Tech. B25, 2224-2227 (2007).

 

S. C. Lee, D. L. Huffaker and S. R. J. Brueck, Faceting of a Quasi-Two-Dimensional GaAs Crystal in Nanoscale Patterned Growth, Appl. Phys. Lett. 92, 023103 (2008).

 

Y-J. Oh, T. C. Gamble, D. Leonhardt, C-H. Chung, S. R. J. Brueck, C. F. Ivory, G. P. Lopez, D. N. Petsev and S. M. Han, Monitoring FET Flow Control and Wall Adsorption of Charged Fluorescent Dye Molecules in Nanochannels Integrated into a Multiple Internal Reflection Infrared Waveguide, Lab on a Chip 8, 251-258 (2008).

 

W. Pan, S. K. Lyo, J. L. Reno, J. A. Simmons, D. Li and S. R. J. Brueck, Negative Differential Conductance in Two-Dimensional Electron Grids, Appl. Phys. Lett. 92, 052104 (2008).

 

D. Xia, Z. Ku, D. Li and S. R. J. Brueck, Formation of Hierarchical Particle Arrays and Nanoparticle Patterns with Colloidal Lithography and Two-Step Self-Assembly: Microspheres atop Nanospheres, Chem. of Mater. 20, 1847-1854 (2008).

 

Y. Kuznetsova, A. Neumann and S. R. J. Brueck, Imaging Interferometric Microscopy, Jour. Opt. Soc. Amer. A25, 811-822 (2008).

 

R. D. R. Bhat, N. C. Panoiu, S. R. J. Brueck and R. M. Osgood, Jr., Enhancing the Signal-to-Noise Ratio of an Infrared Detector with a Circular Metal Grating, Opt. Exp. 16, 4588 – 4596 (2008).

 

L. Xue, S. R. J. Brueck and R. Kaspi, High Power, Continuous Wave, Single Longitudinal Mode Operation of an Opticallly Pumped DFB Laser at  ~ 3.64 m, Phot.. Tech. Lett. 20, 727 (2008).

 

A. Neumann, Y. Kuznetsova and S. R. J. Brueck, Structured Illumination for the Extension of Imaging Interferometric Microscopy, Opt. Exp. 16, 6785-6793 (2008).

 

D. Xia, T. C. Gamble, E. Mendoza, S. J. Koch, X. He, G. P. Lopez and S. R. J. Brueck, DNA Transport in Hierarchically Structured Colloidal Nanoparticle Porous-Wall Nanochannels  Nano Lett. 8, 1610-1618 (2008).

Synergistic Activities

National Academy Panels: Nanophotonics, DIA Threat Warning

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David Kelley
University of California at Merced
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Lincoln Lauhon
Morris E. Fine Junior Professor of Materials and Manufacturing Northwestern UniversityMaterials Science and Engineering

Lincoln Lauhon is the Morris E. Fine Junior Professor of Materials and Manufacturing in the Department of Materials Science and Engineering at Northwestern University. His multidisciplinary research group pursues advances in the synthesis and characterization of new nanostructured materials with a focus on one-dimensional semiconductor nanowires.  Recently, Dr. Lauhon’s group demonstrated a technique to map the composition of a single semiconductor nanowire in three dimensions with single atom sensitivity and sub-nm resolution.  The group also combines electronic transport measurements of nanowire devices with scanned probe microscopy to establish new methods for quantifying the electronic properties of materials on the nanoscale.  By developing new approaches to the integrated analysis of nanostructure composition and properties, the Lauhon group is establishing a basis for engineering new materials with extraordinary electronic, optical, and magnetic properties.  Dr. Lauhon received the National Science Foundation CAREER award in 2005, the Department of Materials Science and Engineering “Teacher of the Year” award in 2006, an Alfred P. Sloan Research Fellowship in Chemistry in 2007, and was named a Camille Dreyfus Teacher-Scholar in 2008.

Prior to joining Northwestern in July of 2003, Dr. Lauhon pursued postdoctoral research with Professor Charles Lieber in the Department of Chemistry and Chemical Biology at Harvard University.  At Harvard, Dr. Lauhon developed new methods for synthesizing novel semiconductor nanostructures and built unique nanoscale devices enabled by advances in synthesis.  In total, the publications describing these advances have been cited over 2200 times.  Dr. Lauhon obtained his Ph.D. in Physics from Cornell University in 2000 under the guidance of Professor Wilson Ho.  He was awarded the Nottingham Prize at the 60th Physical Electronics Conference for work included in his thesis, entitled “The Initiation and Characterization of Single-Molecule Excitations with a Scanning Tunneling Microscope”.  Dr. Lauhon obtained a B.S. in Physics with Highest Honors from the University of Michigan in 1993.  While at Michigan, he studied magnetic anisotropy in metallic superlattices with Professor Roy Clarke.

Education and Training

University of Michigan, Physics, B.S. w/ Highest Honors, 1993

Cornell University, Physics, PhD, 2000

Harvard University, Chemistry, Postdoctoral Fellowship, 2000-2003

Research and Professional Experience

Professor, Morris E. Fine Junior Professor of Materials and Manufacturing, Northwestern university (2006 to Present)

Assistant Professor, Department of Materials Science and Engineering, Northwestern University (2003 to Present)

Selected Publications

“High-resolution detection of Au catalyst atoms in silicon nanowires,” J.E. Allen, E.R. Hemesath, D.E. Perea, J.L. Lensch-Falk, Z.Y. Li, F. Yin, M.H. Gass, P. Wang, A.L. Bleloch, R.E. Palmer, L.J. Lauhon, Nature Nanotechnology 3, 168 (2008).

“Dendritic nanowire growth mediated by a self-assembled catalyst,” S.J. May, J.G. Zheng, B.W. Wessels and L. J. Lauhon, Advanced Materials 17, 598-602 (2005).

“Syntaxial growth of Ge/Mn-germanide nanowire heterostructures,” J. L. Lensch-Falk, E. R. Hemesath and L. J. Lauhon, Nano Letters, in press (2008).

“Ferromagnetic self-assembled MnAs quantum dots on InAs nanowires,” D.G. Ramlan, S.J. May, J.G. Zheng, J.E. Allen, B.W. Wessels and L.J. Lauhon, Nano Letters 6, 50 (2006).

“Three-dimensional nanoscale composition mapping of a semiconductor nanowire,” D.E. Perea, J.E. Allen, S.J. May, B.W. Wessels, D.N. Seidman and L.J. LauhonNano Letters 6, 151 (2006).

“Quantitative Measurement of the Electron and Hole Mobility-Lifetime Products in Semiconductor Nanowires,” Y. Gu, J.P. Romankiewicz, J.K. David, J.L. Lensch and L.J. Lauhon, Nano Letters 6, 948 (2006).

“Near-field scanning photocurrent microscopy of a nanowire photodetector,” Y. Gu, E.S. Kwak, J.L. Lensch, J.E. Allen, T.W. Odom and L.J. Lauhon, Appl. Phys. Lett. 87, 043111 (2005).

“Epitaxial core-shell and core-multishell nanowire heterostructures,” L.J. Lauhon, M.S. Gudiksen, C.L. Wang and C.M. Lieber, Nature 420, 57-61 (2002).

“Growth of nanowire superlattice structures for nanoscale photonics and electronics,” M.S. Gudiksen, L.J. Lauhon, J. Wang, D.C. Smith and C.M. Lieber, Nature 415, 617-620 (2002).

“Logic gates and computation from assembled nanowire building blocks,” Y. Huang, X.F. Duan, Y. Cui, L.J. Lauhon, K.H. Kim and C.M. Lieber, Science 294, 1313-1317 (2001).

Synergistic Activities

Co-organizer, MRS Fall 2008 Symposium LL on Nanowires

MRSEC IRG-4 Co-Director (2007-present)

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Rohit Prasankumar
Technical Staff Member Los Alamos National Laboratory (LANL)Center for Integrated Nanotechnologies (CINT)

Rohit Prasankumar is a Technical Staff Member in the Center for Integrated Nanotechnologies (CINT) at Los Alamos National Laboratory. His primary research interests are in the measurement of dynamics in complex functional materials with high temporal and spatial resolution over a broad spectral range, with additional interests in the development and application of novel techniques for characterizing nanophotonic devices including metamaterials and photonic crystal microcavities.

Dr. Prasankumar received a B.S. in Electrical Engineering with High Honors from the University of Texas at Austin (1997) and the M.S. (1999) and Ph.D. (2003) degrees in Electrical Engineering from MIT.  His thesis work, completed in 2003, concentrated on designing, fabricating, and characterizing novel non-epitaxially grown silica films doped with semiconductor quantum dots for self-starting mode-locking in solid state lasers.  He also developed and implemented novel ultrafast solid-state laser designs aimed at reducing the cost of femtosecond laser sources.

Dr. Prasankumar became a postdoctoral research associate at LANL in August 2003, focusing on ultrafast mid-to-far-infrared dynamics in semiconductor nanostructures and strongly correlated compounds. He performed mid-IR studies on correlated electron materials such as the colossal magnetoresistance pyrochlore Tl2Mn2O7 and the charge-ordered manganite Nd0.5Sr0.5MnO3, discovering unique carrier dynamics related to charge-spin correlations as well as ferromagnetic and charge ordering. In addition, his experiments on semimetallic ErAs:GaAs nanoislands demonstrated their viability as a novel THz detection system.

Since becoming a staff member in early 2006, Dr. Prasankumar has worked on a wide range of projects, both independently and in collaboration with CINT users.  His primary focus has been the measurement of ultrafast carrier dynamics in semiconductor nanostructures across multiple spatial and temporal dimensions.  In particular, he has initiated a significant effort at CINT to explore carrier dynamics in one-dimensional nanostructures, revealing the dominance of surface effects and defect states over carrier relaxation in these systems.  Additional projects have focused on the measurement of carrier dynamics in solar cell devices and the experimental demonstration of optical nanocircuits.

Dr. Prasankumar has authored or co-authored 21 journal publications and proceedings and 58 conference presentations (including 18 invited talks) since 1999.

Education and Training

B. S. in Electrical Engineering, The University of Texas at Austin, 1997

M. S. in Electrical Engineering, Massachusetts Institute of Technology, 1999

Ph. D. in Electrical Engineering, Massachusetts Institute of Technology, 2003

Research and Professional Experience

Los Alamos National Laboratory, Technical Staff Member (2/2006 – present)

Los Alamos National Laboratory, Postdoctoral Research Associate (8/2003 – 2/2006)

MIT, Graduate Research Assistant, Teaching Assistant (8/1997 – 6/2003)

Undergraduate Research Assistant. The University of Texas at Austin (6/1995-5/1997)

Lawrence Livermore National Laboratory, Undergraduate Research Fellow (Summer 1996)

Undergraduate Intern, Entergy Corporation (6/1994-8/1994)

Selected Publications

“Ultrafast electron and hole dynamics in germanium nanowires,” R.P. Prasankumar, S.G. Choi, S.A. Trugman, S.T. Picraux and A.J. Taylor, Nano Lett. 8, 1619 (2008).

“Ultrafast carrier dynamics in an InAs/InGaAs quantum-dots-in-a-well heterostructure,” R.P. Prasankumar, R.S. Attaluri, R.D. Averitt, J. Urayama, N. Weisse-Bernstein, P. Rotella, A. Stintz, S. Krishna and A. J. Taylor, Opt. Exp. 16, 1165 (2008).

“Enhanced photosusceptibility near Tc for the light-induced insulator-to-metal phase transition in vanadium dioxide,” D.J. Hilton, R. P. Prasankumar, S. Fourmaux, A. Cavalleri, D. Brassard, M.A. El Khakani, J.C. Kieffer, A.J. Taylor and R.D. Averitt, Phys. Rev. Lett. 99, 226401 (2007).

“Phase inhomogeneities in the charge-and-orbital ordered manganite Nd0.5Sr0.5MnO3 revealed through polaron dynamics,” R.P. Prasankumar, S. Zvyagin, K.V. Kamenev, G. Balakrishnan, D. Mck. Paul, A.J. Taylor and R.D. Averitt, Phys. Rev. B: Rapid Comm. 76, 020402(R) (2007).

“On photo-induced phenomena in complex materials: Probing quasiparticle dynamics using infrared and far-infrared pulses,” D. J. Hilton*, R. P. Prasankumar*, S.A. Trugman, A.J. Taylor and R.D. Averitt, invited review article, J. Phys. Soc. Jpn. 75, 011006 (2006). (*both authors contributed equally to this work)

“Coupled charge-spin dynamics in the magnetoresistive pyrochlore Tl2Mn2O7 probed using ultrafast midinfrared spectroscopy,” R.P. Prasankumar, H. Okamura, H. Imai, Y. Shimakawa, Y. Kubo, S.A. Trugman, A.J. Taylor and R.D. Averitt, Phys. Rev. Lett. 95, 267404 (2005).

“Carrier dynamics in self-assembled ErAs nanoislands embedded in GaAs measured by optical pump-THz probe spectroscopy,” R. P. Prasankumar, A. Scopatz, D.J. Hilton, A.J. Taylor, R.D. Averitt, J. Zide and A.C. Gossard, Appl. Phys. Lett. 86, 201105 (2005).

“High speed femtosecond pump-probe spectroscopy by use of a two-dimensional smart pixel detector array,” S. Bourquin, R.P. Prasankumar, U. Morgner, F. X. Kärtner, J. G. Fujimoto, T. Lasser and R. P. Salathe, Opt. Lett. 28, 1588 (2003).

“Self-starting mode locking in a Cr:forsterite laser using non-epitaxially grown semiconductor-doped silica films,” R.P. Prasankumar, C. Chudoba, J.G. Fujimoto, P. Mak and M.F. Ruane, Opt. Lett. 27, 1564 (2002).

“Self-starting mode locking and Kerr-lens mode locking of a Ti:Al2O3 laser by use of semiconductor-doped glass structures,” I.P. Bilinsky, R.P. Prasankumar and J.G. Fujimoto, J. Opt. Soc. Am. B 16, 546 (1999).

Synergistic Activities

Principal Investigator for the research project “Tracking Carrier Dynamics in Nitride-Based Nanowires and Nanophotonic Devices” (funded by the National Nanotechnology Enterprise Development Center), (2007-2009).

Co-investigator on the project: “Quantum Electronic Phenomena and Structures” (funded by the DOE Office of Basic Energy Sciences), (2006-present).

Member of the organizing committee for the Nanowire Symposium at the CINT User Workshop, (2008).

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Jim Speck
University of California at Santa Barbara
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External Advisory Board

Photo of Dan Dapkus
Dan Dapkus
University of Southern California
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Colin Humphreys
Cambridge University
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Arto Nurmikko
Brown University
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Tom Picraux
Los Alamos National Laboratory (LANL)
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Fred Welsh
Radcliffe Advisors, Inc.
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