General Info

Contact Information:

Voice (505) 844-7092

Fax (505) 844-4045

Cell (505) 480-4267

Email: jytsao@sandia.gov.

Brief Bio

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 embedded-network models of the evolution of social knowledge – an emerging 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. During 1993-2000, he served as manager of various technical groups at Sandia National Laboratories in the area of compound semiconductor materials and devices. In 1998, he took a sabbatical at the Institute of Materials Research and Engineering in Singapore, where he developed and gave a comprehensive series of twelve lectures on compound semiconductor epitaxy.

Jeff has authored or co-authored over 150 publications, holds 8 U.S. patents, and is author of a 1993 research monograph “Materials Fundamentals of Molecular Beam Epitaxy,” for which he won Martin Marietta’s 1994 Author of the Year and Jefferson Cup awards. He co-authored an influential 1999 white paper outlining the potential of Solid-State Lighting, and edited the comprehensive 2002 U.S. Solid-State Lighting Roadmap. He has helped the Office of Basic Energy Science coordinate two recent workshops and reports: one in 2005 on “Basic Research Needs in Solar Energy Utilization,” and another in 2006 on “Basic Research Needs in Solid-State Lighting.”

Jeff has been active in various professional societies, including the Materials Research Society, for which 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 was elected Fellow of the American Physical Society in 1996.

Full C.V. (Mar 2008)

Family

Jeff is married to Sylvia S. Tsao, and has two children, Emil and Eugene.

Evolutionary epistemology

Galileo’s Stream: A Framework for Understanding Knowledge Production (Jeff Tsao, Kevin Boyack, Mike Coltrin, Jessica Turnley, Wil Gauster) (SAND 2006-7622J) (Research Policy 37, 330-352) (March 2008)

This paper introduces a new framework for understanding knowledge production in which: knowledge is produced in stages (along a research to development continuum) and in three discrete categories (science and understanding, tools and technology, and societal use and behavior); and knowledge in the various stages and categories is produced both non-interactively and interactively.

energy

The World’s Appetite for Light: A Simple Empirical Expression Spanning Three Centuries and Six Continents (Jeff Tsao, Paul Waide) (SAND 2007-4791J) (May 2008 revision, submitted to The Energy Journal)

A simple empirical expression, in which consumption of artificial light depends linearly on the ratio between gross domestic product and cost of light, is found to be consistent with historical and contemporary data spanning three centuries, six continents, and seven orders of magnitude. The implication is that, in recent centuries, the income and price elasticities of demand for artificial light have been roughly unity. Given that lighting accounts for 6.5% of world energy consumption and is poised at the brink of a technology revolution, these elasticities are of great current interest for forecasting future energy consumption and informing public policy.

Some Simple Physics of Global Warming (Jeff Tsao) (March 2008) (SAND 2008-2255P) and notes

These viewgraphs are based on a tutorial lecture given for a high school physics class at the Bosque School in Albuquerque.

Basic Research Needs in Solid-State Lighting (Julie Phillips, Paul Burrows, Chairs) (October 2006)

This report is based on a U.S. Department of Energy Office of Basic Energy Science’s Workshop on Solid-State Lighting (SSL), May 22–24, 2006, chaired by Julie Phillips and Paul Burrows. It examines the gap separating current state-of-the-art SSL technology from an energy efficient, high-quality, and economical SSL technology suitable for general illumination; and identifies the most significant fundamental scientific challenges and research directions that would enable that gap to be bridged.

Solar FAQs (Jeff Tsao, Nate Lewis, George Crabtree) (SAND 2006-2818P) and related informal talk (SAND 2006-2821P) (April 2006)

This white paper asks and answers a series of questions regarding the potential of the sun to supply energy to the world. The questions are drawn in large part from the U.S. Department of Energy Office of Basic Energy Science’s recent report on Basic Research Needs in Solar Energy Utilization. The answers are given in a format suitable for a lay technical audience, and are supplemented by detailed calculations and comprehensive references.

Basic Research Needs in Solar Energy Utilization (Nate Lewis, George Crabtree, Chairs) (October 2005)

This report is based on a U.S. Department of Energy Office of Basic Energy Science’s Workshop on Solar Energy Utilization, April 18–21, 2005, chaired by Nate Lewis and George Crabtree. It examines the challenges and opportunities for the development of solar energy as a competitive energy source and identifies the technical barriers to large-scale implementation of solar energy and the basic research directions showing promise to overcome them.

semiconductor materials and devices

The World of Compound Semiconductors

This is a book started in 2002, worked on for about a year, then abandoned. Its intent was to have been to provide an integrated guide to the science, technology and applications of the compound III-V semiconductors. Its unique aspect was to have been its emphasis and organization around an objective database (linked file is in procite format) of the most highly-cited journal articles and U.S. patents in the field. Comments and avenues for its continuation are most welcome.

Optically-pumped long-wavelength vertical-cavity surface-emitting laser with high modulation bandwidth (MV Ramana Murty, D Xu, CC Lin, CL Shieh, JY Tsao, J Cheng, Appl Phys Lett 86, 061108, 2006)

Electrically pumped long-wavelength VCSEL with air gap DBR and methods of fabrication (CL Shieh, JY Tsao, US Patent 6,696,308, February 24 2004)

Segmented-mirror VCSEL (JY Tsao, CL Shieh, PD Dapkus, J Yang, US Patent 6,594,294, July 15 2003)

Semiconductor Epitaxy: Science, Technology and Applications 40MB (July-November 1998) (SAND 2007-1800P)

This series of twelve lectures was given over four months at the Institute of Materials and Engineering (IMRE) in Singapore. The series began with an overview of materials and device families and properties, and of epitaxy growth techniques such as molecular beam epitaxy (MBE) and chemical-vapor deposition (CVD). Then, the science of epitaxy was discussed, including vapor, surface, thin film and bulk phenomena. Finally, the series ended with an overview of the technology and applications of epitaxy, with attention to particular III/V alloy systems as well as to manufacturing issues.

Materials Fundamentals of Molecular Beam Epitaxy (Academic Press, 1993) and figures (SAND 2007-1801P)

This book gathers together the basic materials science principles that apply to MBE, and treats in great depth its most important aspects. Throughout, it makes use of thermodynamic and statistical calculations based on intuitive and physically motivated semi-empirical models.

Solid-State Lighting

Ultra-Efficient Solid-State Lighting: Performance Frontier, Progress, Challenges (Jeff Tsao) (Nov 2008) (SAND 2008-7752P) and notes

This talk was given at the 21^st Annual Meeting of the IEEE Lasers & Electro-Optics Society in Newport Beach, CA.

Research challenges to ultra-efficient inorganic solid-state lighting (Julie Phillips, Mike Coltrin, Mary Craford, Art Fischer, Mike Krames, Regina Mueller-Mach, Gerd Mueller, Yoshi Ohno, Lauren Rohwer, Jerry Simmons, Jeff Tsao) (SAND 2007-5470J) and figures (Laser and Photonics Reviews 1, 307-333 (November 2007)

This review article discusses approaches to inorganic solid-state lighting that could conceivably achieve ultra-high (70% or greater) efficiency, and the significant research questions and challenges that would need to be addressed if one or more of these approaches were to be realized.

International trends in solid state lighting: analyses of the article and patent literature (Kevin Boyack, Jeff Tsao, Ann Miksovic, Mark Huey) (SAND2008-4564) and figures (October 2006)

This report analyzes a comprehensive dataset of English-language articles and U.S. patents published or issued in the knowledge domain of electroluminescent materials and phenomena. A number of analyses were performed, including: identification of knowledge sub-domains of historical and recent importance, and trends over time of the contributions of various nations and continents to the knowledge domain and its sub-domains.

Solid-State Lighting: a Case Study in Science and Technology Evolution (Jeff Tsao) (July 2006) (SAND 2006-4047A)

This talk was given at the 2006 China International Forum on Solid-State Lighting (CIFSSL) in Shenzhen, China.

Technology Footprinting and Solid-State Lighting (Jeff Tsao, Kevin Boyack, Mark Huey, Ann Miksovic, June 2006) (SAND 2006-7621P)

This work was sponsored by the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Building Technologies Program. This set of viewgraphs explores the development of a tool that might be called “technology footprinting,” and the preliminary application of that tool to solid-state lighting.

Solid-State Lighting: the Potential and the Challenges (Jeff Tsao) (August 11-12 2005) (SAND 2005-4894A)

These two lectures were given in two half-days at the Institute of Materials Research and Engineering (IMRE) in Singapore.

Evolution of Solid-State Lighting: Market Pull and Technology Push (Jeff Tsao) (April 2005) (SAND 2008-2251C) and notes

This talk was given at the 2005 China International Forum on Solid-State Lighting (CIFSSL) in Xiamen, China.

Solid-State Lighting: Lamps, Chips and Materials for Tomorrow (Jeff Tsao) (IEEE Circuits and Devices Magazine Vol 20 Issue 3 pp 28-37, May-June 2004) (SAND 2003-3018J)

The aims of this article were twofold. First, a brief overview of conventional and SSL lighting technologies was given. Second, a description was given of some of the simplest but most important lamp, chip, and materials design choices that would need to be made if SSL technology is to fulfill its promise for general illumination.

Final Report on Grand Challenge LDRD Project: A Revolution in Lighting -- Building the Science and Technology Base for Ultra-Efficient Solid-State Lighting (SAND 2004-2365, May 2004)

This SAND report was the final report on Sandia’s Grand Challenge LDRD SSL Project This project is considered one of Sandia’s most successful GCLDRDs. This report reviews not only technical highlights, but also the genesis of the idea for SSL, the initiation of the SSL GCLDRD, and the goals, scope, success metrics, and evolution of the SSL GCLDRD over the course of its life.

Solid-State Lighting: Roadmap (Jeff Tsao) (Laser Focus World Vol 39 Issue 5 pp S11-S14, May 2003) (SAND 2003-0556J)

A summary of the 2002 SSL roadmap, with a special emphasis on energy savings projections.

Light Emitting Diodes (LEDs) for General Illumination (Jeff Tsao, Ed.) (November 2002) (SAND 2002-3408P)

This report was the first comprehensive SSL technology roadmap, and provided quantitative enumeration of key technology targets, prioritization of research challenges, and key decisions related to competing approaches. It also discussed lighting systems issues necessary to achieve mass penetration of LEDs in the marketplace.

Solid-State Lighting: Illumination through Semiconductor Science Website

A website, actively maintained from December 2001 through September 2006, whose intent was “to gather together information relevant to solid-state lighting, and to help stimulate the development of the science and technology foundation necessary to enable the promise and potential of solid-state lighting.”

The Case for a National Research Program on Semiconductor Lighting (Roland Haitz, Fred Kish, Jeff Tsao, Jeff Nelson, October 1999) (SAND 2000-1612)

This white paper was the first to discuss the vast technological and energy-savings potential of solid-state lighting technology.