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How technoscientific knowledge advances: A Bell-Labs-inspired architecture

Research Policy

Tsao, Jeffrey Y.; Narayanamurti, Venkatesh

Understanding how science and technology advance has long been of interest to diverse scholarly communities. Thus far, however, such understanding has not been easy to map to, and thus to improve, the operational practice of research and development. Indeed, one might argue that the operational practice of research and development, particularly its exploratory research half, has become less effective in recent decades. In this paper, we describe a rethinking of how science and technology advance, one that is consistent with many (though not all) of the perspectives of the scholarly communities just mentioned, and one that helps bridge the divide between theory and practice. The result is an architecture we call “Bell's Dodecants,” to reflect its six mechanisms and two flavors, and their balanced nurturing at Bell Labs, the iconic 20th century industrial research and development laboratory.

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AI for Technoscientific Discovery: A Human-Inspired Architecture

Journal of Creativity (Online)

Tsao, Jeffrey Y.; Abbott, Robert G.; Crowder, Douglas C.; Desai, Saaketh D.; Dingreville, Remi P.; Fowler, James E.; Garland, Anthony G.; Murdock, Jaimie M.; Steinmetz, Scott T.; Yarritu, Kevin A.; Johnson, Curtis M.; Stracuzzi, David J.; Padmanabha Iyer, Prasad P.

We present a high-level architecture for how artificial intelligences might advance and accumulate scientific and technological knowledge, inspired by emerging perspectives on how human intelligences advance and accumulate such knowledge. Agents advance knowledge by exercising a technoscientific method—an interacting combination of scientific and engineering methods. The technoscientific method maximizes a quantity we call “useful learning” via more-creative implausible utility (including the “aha!” moments of discovery), as well as via less-creative plausible utility. Society accumulates the knowledge advanced by agents so that other agents can incorporate and build on to make further advances. The proposed architecture is challenging but potentially complete: its execution might in principle enable artificial intelligences to advance and accumulate an equivalent of the full range of human scientific and technological knowledge.

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The Structure and Evolution of Science and Technology: A Modern Synthesis (UUR LDRD Final Report)

Tsao, Jeffrey Y.

This project matured a new understanding (a “modern synthesis”) of the structure and evolution of science and technology. It created an understanding and framework for how Sandia National Labs, the Department of Energy, and the nation, might improve their research productivity, with significant ramifications on national security and economic competitiveness.

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Ultra-Wide-Bandgap Semiconductors: Challenges and Opportunities (invited)

Kaplar, Robert K.; Allerman, A.A.; Armstrong, Andrew A.; Crawford, Mary H.; Pickrell, Gregory P.; Dickerson, Jeramy R.; Flicker, Jack D.; Neely, Jason C.; Paisley, Elizabeth A.; Baca, Albert; Klein, Brianna A.; Douglas, Erica A.; Reza, Shahed R.; Binder, Andrew B.; Yates, Luke Y.; Slobodyan, Oleksiy; Sharps, Paul; Simmons, Jerry; Tsao, Jeffrey Y.; Hollis, Mark; Johnson, Noble; Jones, Ken; Pavlidis, Dimitris; Goretta, Ken; Nemanich, Bob; Goodnick, Steve; Chowdhury, Srabanti

Abstract not provided.

AI-Enhanced Co-Design for Next-Generation Microelectronics: Innovating Innovation (Workshop Report)

Descour, Michael R.; Tsao, Jeffrey Y.; Stracuzzi, David J.; Wakeland, Anna K.; Schultz, David R.; Smith, William; Weeks, Jacquilyn A.

On April 6-8, 2021, Sandia National Laboratories hosted a virtual workshop to explore the potential for developing AI-Enhanced Co-Design for Next-Generation Microelectronics (AICoM). The workshop brought together two themes. The first theme was articulated in the 2018 Department of Energy Office of Science (DOE SC) “Basic Research Needs for Microelectronics” (BRN) report, which called for a “fundamental rethinking” of the traditional design approach to microelectronics, in which subject matter experts (SMEs) in each microelectronics discipline (materials, devices, circuits, algorithms, etc.) work near-independently. Instead, the BRN called for a non-hierarchical, egalitarian vision of co-design, wherein “each scientific discipline informs and engages the others” in “parallel but intimately networked efforts to create radically new capabilities.” The second theme was the recognition of the continuing breakthroughs in artificial intelligence (AI) that are currently enhancing and accelerating the solution of traditional design problems in materials science, circuit design, and electronic design automation (EDA).

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Creative Outcome as Implausible Utility

Review of General Psychology

Tsao, Jeffrey Y.; Ting, C.L.; Johnson, Curtis M.

Two perspectives are used to reframe Simonton’s recent three-factor definition of creative outcome. The first perspective is functional: that creative ideas are those that add significantly to knowledge by providing both utility and learning. The second perspective is calculational: that learning can be estimated by the change in probabilistic beliefs about an idea’s utility before and after it has played out in its environment. The results of the reframing are proposed conceptual and mathematical definitions of (a) creative outcome as the product of two overarching factors (utility and learning) and (b) learning as a function of two subsidiary factors (blindness reduction and surprise). Learning will be shown to depend much more strongly on surprise than on blindness reduction, so creative outcome may then also be defined as “implausible utility.”.

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The electrification of energy: Long-term trends and opportunities

MRS Energy and Sustainability

Tsao, Jeffrey Y.; Fouquet, Roger; Schubert, E.F.

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Nurturing transformative U.S. energy research: Two guiding principles

MRS Energy and Sustainability

Tsao, Jeffrey Y.; Narayanamurti, Venkatesh

We raise for debate and discussion what in our opinion is a growing mis-control and mis-protection of U.S. energy research. We outline the origin of this mis-control and mis-protection, and propose two guiding principles to mitigate them and instead nurture research: (1) focus on people, not projects; and (2) culturally insulate research from development, but not science from technology. Energy research is critical to continuing advances in human productivity and welfare. In this Commentary, we raise for debate and discussion what in our view is a growing mis-control and mis-protection of U.S. energy research. This flawed approach originates in natural human tendencies exacerbated by an historical misunderstanding of research and development, science and technology, and the relationships between them. We outline the origin of the mis-control and mis-protection, and propose two guiding principles to mitigate them and instead nurture research: (i) focus on people, not projects; and (ii) culturally insulate research from development, but not science from technology. Our hope is to introduce these principles into the discourse now, so they can help guide policy changes in U.S. energy research and development that are currently being driven by powerful geopolitical winds. Summary: Two foundational guiding principles are proposed to mitigate a growing mis-control and mis-protection of U.S. energy research, and instead to nurture it.

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Quantum Nanofabrication: Mechanisms and Fundamental Limits

Wang, George T.; Coltrin, Michael E.; Lu, Ping L.; Miller, Philip R.; Leung, Benjamin; Xiao, Xiaoyin; Sapkota, Keshab R.; Leonard, Francois L.; Bran Anleu, Gabriela A.; Koleske, Daniel D.; Tsao, Jeffrey Y.; Balakrishnan, Ganesh; Addamane, Sadhvikas; Nelson, Jeffrey S.

Quantum-size-controlled photoelectrochemical (QSC-PEC) etching, which uses quantum confinement effects to control size, can potentially enable the fabrication of epitaxial quantum nanostructures with unprecedented accuracy and precision across a wide range of materials systems. However, many open questions remain about this new technique, including its limitations and broader applicability. In this project, using an integrated experimental and theoretical modeling approach, we pursue a greater understanding of the time-dependent QSC-PEC etch process and to uncover the underlying mechanisms that determine its ultimate accuracy and precision. We also seek to broaden our understanding of the scope of its ultimate applicability in emerging nanostructures and nanodevices.

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Sandia National Laboratories Strategic Context Workshop Series 2017: National Security Futures for Strategic Thinking

Keller, Elizabeth J.; Roll, Elizabeth R.; Aamir, Munaf S.; Bull, Diana L.; Deland, Sharon M.; Haddal, Chad H.; Passell, Howard D.; Foley, John T.; Harwell, Amber S.; Otis, Monique O.; Backus, George A.; Jones, Wendell J.; Bawden, Michael G.; Craft, Richard L.; Kistin, David J.; Martin, Jeffrey B.; McNicol, Bradley R.; Vannoni, Michael G.; Trost, Lawrence C.; Tsao, Jeffrey Y.; Weaver, Karla W.

In August 2017, Sandia convened five workshops to explore the future of advanced technologies and global peace and security through the lenses of deterrence, information, innovation, nonproliferation, and population and Earth systems.

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Engineering a Better Future: Interplay between Engineering, Social Sciences, and Innovation

Engineering a Better Future: Interplay between Engineering, Social Sciences, and Innovation

Subrahmanian, Eswaran; Odumosu, Toluwalogo; Tsao, Jeffrey Y.

This open access book examines how the social sciences can be integrated into the praxis of engineering and science, presenting unique perspectives on the interplay between engineering and social science. Motivated by the report by the Commission on Humanities and Social Sciences of the American Association of Arts and Sciences, which emphasizes the importance of social sciences and Humanities in technical fields, the essays and papers collected in this book were presented at the NSF-funded workshop ‘Engineering a Better Future: Interplay between Engineering, Social Sciences and Innovation’, which brought together a singular collection of people, topics and disciplines. The book is split into three parts: A. Meeting at the Middle: Challenges to educating at the boundaries covers experiments in combining engineering education and the social sciences; B. Engineers Shaping Human Affairs: Investigating the interaction between social sciences and engineering, including the cult of innovation, politics of engineering, engineering design and future of societies; and C. Engineering the Engineers: Investigates thinking about design with papers on the art and science of science and engineering practice.

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LED lighting efficacy: Status and directions

Comptes Rendus. Physique

Pattison, Paul M.; Hansen, Monica; Tsao, Jeffrey Y.

A monumental shift from conventional lighting technologies (incandescent, fluorescent, high intensity discharge) to LED lighting is currently transpiring. The primary driver for this shift has been energy and associated cost savings. LED lighting is now more efficacious than any of the conventional lighting technologies with room to still improve. Near term, phosphor converted LED packages have the potential for efficacy improvement from 160 lm/W to 255 lm/W. Longer term, color-mixed LED packages have the potential for efficacy levels conceivably as high as 330 lm/W, though reaching these performance levels requires breakthroughs in green and amber LED efficiency. LED package efficacy sets the upper limit to luminaire efficacy, with the luminaire containing its own efficacy loss channels. In this paper, based on analyses performed through the U.S. Department of Energy Solid State Lighting Program, various LED and luminaire loss channels are elucidated, and critical areas for improvement identified. Beyond massive energy savings, LED technology enables a host of new applications and added value not possible or economical with previous lighting technologies. These include connected lighting, lighting tailored for human physiological responses, horticultural lighting, and ecologically conscious lighting. Finally, none of these new applications would be viable if not for the high efficacies that have been achieved, and are themselves just the beginning of what LED lighting can do.

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Visible Quantum Nanophotonics

Subramania, Ganapathi S.; Wang, George T.; Fischer, Arthur J.; Wierer, Jonathan J.; Tsao, Jeffrey Y.; Koleske, Daniel K.; Coltrin, Michael E.; Agarwal, Sapan A.; Anderson, P.D.; Leung, Ben

The goal of this LDRD is to develop a quantum nanophotonics capability that will allow practical control over electron (hole) and photon confinement in more than one dimension. We plan to use quantum dots (QDs) to control electrons, and photonic crystals to control photons. InGaN QDs will be fabricated using quantum size control processes, and methods will be developed to add epitaxial layers for hole injection and surface passivation. We will also explore photonic crystal nanofabrication techniques using both additive and subtractive fabrication processes, which can tailor photonic crystal properties. These two efforts will be combined by incorporating the QDs into photonic crystal surface emitting lasers (PCSELs). Modeling will be performed using finite-different time-domain and gain analysis to optimize QD-PCSEL designs that balance laser performance with the ability to nano-fabricate structures. Finally, we will develop design rules for QD-PCSEL architectures, to understand their performance possibilities and limits.

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Recommended Research Directions for Improving the Validation of Complex Systems Models

Vugrin, Eric D.; Trucano, Timothy G.; Swiler, Laura P.; Finley, Patrick D.; Flanagan, Tatiana P.; Naugle, Asmeret B.; Tsao, Jeffrey Y.; Verzi, Stephen J.

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Footprint of Sandia's August 15 2016 Informal Idea Exploration Session on "Towards an Engineering and Applied Science of Research"

Tsao, Jeffrey Y.; Fleming Lindsley, Elizabeth S.; Heffelfinger, Grant S.; Narayanamurti, Venkatesh; Schneider, Rick; Starkweather, Lynne M.; Ting, Christina T.; Yajima, Rieko; Bauer, Travis L.; Coltrin, Michael E.; Guy, Donald W.; Jones, Wendell J.; Mareda, John F.; Nenoff, T.M.; Turnley, Jessica G.

On August 15, 2016, Sandia hosted a visit by Professor Venkatesh Narayanamurti. Prof Narayanamurti (Benjamin Peirce Research Professor of Technology and Public Policy at Harvard, Board Member of the Belfer Center for Science and International Affairs, former Dean of the School of Engineering and Applied Science at Harvard, former Dean of Engineering at UC Santa Barbara, and former Vice President of Division 1000 at Sandia). During the visit, a small, informal, all-day idea exploration session on "Towards an Engineering and Applied Science of Research" was conducted. This document is a brief synopsis or "footprint" of the presentations and discussions at this Idea Exploration Session. The intent of this document is to stimulate further discussion about pathways Sandia can take to improve its Research practices.

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Creating wide band gap LEDs without P-doping

Device Research Conference - Conference Digest, DRC

Agarwal, Sapan A.; Dickerson, Jeramy R.; Tsao, Jeffrey Y.

Wide band gap semiconductors like AlN typically cannot be efficiently p-doped: acceptor levels are far from the valence band-edge, preventing holes from activating. This means that pn-junctions cannot be created, and the semiconductor is less useful, a particular problem for deep Ultraviolet (UV) optoelectronics.

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Complex Systems Models and Their Applications: Towards a New Science of Verification, Validation & Uncertainty Quantification

Tsao, Jeffrey Y.; Trucano, Timothy G.; Kleban, S.D.; Naugle, Asmeret B.; Verzi, Stephen J.; Swiler, Laura P.; Johnson, Curtis M.; Smith, Mark A.; Flanagan, Tatiana P.; Vugrin, Eric D.; Gabert, Kasimir G.; Lave, Matthew S.; Chen, Wei; Delaurentis, Daniel; Hubler, Alfred; Oberkampf, Bill

This report contains the written footprint of a Sandia-hosted workshop held in Albuquerque, New Mexico, June 22-23, 2016 on “Complex Systems Models and Their Applications: Towards a New Science of Verification, Validation and Uncertainty Quantification,” as well as of pre-work that fed into the workshop. The workshop’s intent was to explore and begin articulating research opportunities at the intersection between two important Sandia communities: the complex systems (CS) modeling community, and the verification, validation and uncertainty quantification (VVUQ) community The overarching research opportunity (and challenge) that we ultimately hope to address is: how can we quantify the credibility of knowledge gained from complex systems models, knowledge that is often incomplete and interim, but will nonetheless be used, sometimes in real-time, by decision makers?

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III-nitride quantum dots for ultra-efficient solid-state lighting

Laser and Photonics Reviews

Wierer, Jonathan J.; Tansu, Nelson; Fischer, Arthur J.; Tsao, Jeffrey Y.

III-nitride light-emitting diodes (LEDs) and laser diodes (LDs) are ultimately limited in performance due to parasitic Auger recombination. For LEDs, the consequences are poor efficiencies at high current densities; for LDs, the consequences are high thresholds and limited efficiencies. Here, we present arguments for III-nitride quantum dots (QDs) as active regions for both LEDs and LDs, to circumvent Auger recombination and achieve efficiencies at higher current densities that are not possible with quantum wells. QD-based LDs achieve gain and thresholds at lower carrier densities before Auger recombination becomes appreciable. QD-based LEDs achieve higher efficiencies at higher currents because of higher spontaneous emission rates and reduced Auger recombination. The technical challenge is to control the size distribution and volume of the QDs to realize these benefits. If constructed properly, III-nitride light-emitting devices with QD active regions have the potential to outperform quantum well light-emitting devices, and enable an era of ultra-efficient solid-state lighting. (Figure presented.) .

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The art of research: Opportunities for a science-based approach

Lecture Notes in Computer Science

Silva, Austin R.; Avina, Glory E.; Tsao, Jeffrey Y.

Research, the manufacture of knowledge, is currently practiced largely as an “art,” not a “science.” Just as science (understanding) and technology (tools) have revolutionized the manufacture of other goods and services, it is natural, perhaps inevitable, that they will ultimately also be applied to the manufacture of knowledge. In this article, we present an emerging perspective on opportunities for such application, at three different levels of the research enterprise. At the cognitive science level of the individual researcher, opportunities include: overcoming idea fixation and sloppy thinking, and balancing divergent and convergent thinking. At the social network level of the research team, opportunities include: overcoming strong links and groupthink, and optimally distributing divergent and convergent thinking between individuals and teams. At the research ecosystem level of the research institution and the larger national and international community of researchers, opportunities include: overcoming GPA and performance fixation, overcoming narrow measures of research impact, and overcoming (or harnessing) existential/social stress.

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Light-emitting diode technology status and directions: Opportunities for horticultural lighting

Acta Horticulturae

Tsao, Jeffrey Y.; Pattison, P.M.; Krames, Michael R.

Here, light-emitting diode (LED) technology has advanced rapidly over the last decade, primarily driven by display and general illumination applications ("solid-state lighting (SSL) for humans"). These advancements have made LED lighting technically and economically advantageous not only for these applications, but also, as an indirect benefit, for adjacent applications such as horticultural lighting ("SSL for plants"). Moreover, LED technology has much room for continued improvement. In the near-term, these improvements will continue to be driven by SSL for humans (with indirect benefit to SSL for plants), the most important of which can be anticipated.

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The art of research: Opportunities for a science-based approach

Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)

Silva, Austin R.; Avina, Glory E.; Tsao, Jeffrey Y.

Research, the manufacture of knowledge, is currently practiced largely as an “art,” not a “science.” Just as science (understanding) and technology (tools) have revolutionized the manufacture of other goods and services, it is natural, perhaps inevitable, that they will ultimately also be applied to the manufacture of knowledge. In this article, we present an emerging perspective on opportunities for such application, at three different levels of the research enterprise. At the cognitive science level of the individual researcher, opportunities include: overcoming idea fixation and sloppy thinking, and balancing divergent and convergent thinking. At the social network level of the research team, opportunities include: overcoming strong links and groupthink, and optimally distributing divergent and convergent thinking between individuals and teams. At the research ecosystem level of the research institution and the larger national and international community of researchers, opportunities include: overcoming performance fixation, overcoming narrow measures of research impact, and overcoming (or harnessing) existential/social stress.

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Influence of pH on the Quantum-Size-Controlled Photoelectrochemical Etching of Epitaxial InGaN Quantum Dots

Journal of Physical Chemistry C

Xiao, Xiaoyin; Lu, Ping L.; Fischer, Arthur J.; Coltrin, Michael E.; Wang, George T.; Koleske, Daniel K.; Tsao, Jeffrey Y.

Illumination by a narrow-band laser has been shown to enable photoelectrochemical (PEC) etching of InGaN thin films into quantum dots with sizes controlled by the laser wavelength. Here, we investigate and elucidate the influence of solution pH on such quantum-size-controlled PEC etch process. We find that although a pH above 5 is often used for PEC etching of GaN-based materials, oxides (In2O3 and/or Ga2O3) form which interfere with quantum dot formation. At pH below 3, however, oxide-free QDs with self-terminated sizes can be successfully realized.

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The Social Science and Engineering of Research Practice

Science Magazine

Odumosu, T.B.; Tsao, Jeffrey Y.; Crabtree, G.W.; Narayanamurti, V.

The verdict is in: the methods of science can significantly enhance the effectiveness of creative teams. Just ask employers like Google and Facebook who are applying ideas from the social sciences to improve the performance of their organizations.1 Over the last few decades, social scientists, including psychologists, sociologists and anthropologists, have made important strides in developing a scientific understanding of how creative individuals and creative communities operate.

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The Blue LED Nobel Prize: Historical context, current scientific understanding, human benefit

Annalen der Physik

Tsao, Jeffrey Y.; Han, Jung; Haitz, Roland H.; Pattison, P.M.

The authors, Jeffrey Y. Tsao, Jung Han, Roland H. Haitz, and P. Morgan Pattison, on behalf of a large and growing community of scientists and technologists working in III-N semiconductor materials, physics and devices, and of users of the applications they enable congratulate Professors Akasaki, Amano and Nakamura (AAN). The path that connects scientific understanding with tools and technologies is rarely linear. Prevailing scientific understanding often enables and unleashes new tools and technologies. But prevailing scientific understanding is imperfect, and technology researchers must often step, as did AAN, outside its confines for their breakthroughs. the importance of technology breakthroughs is particularly evident in semiconductors: in recent decades, more and more Physics Nobel Prizes have been awarded for technology breakthroughs, and of these by far the most have been for semiconductors.

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Photoelectrochemical etching of epitaxial InGaN thin films: Self-limited kinetics and nanostructuring

Electrochimica Acta

Xiao, Xiaoyin; Fischer, Arthur J.; Coltrin, Michael E.; Lu, Ping L.; Koleske, Daniel K.; Wang, George T.; Polsky, Ronen P.; Tsao, Jeffrey Y.

We report here the characteristics of photoelectrochemical (PEC) etching of epitaxial InGaN semiconductor thin films using a narrowband laser with a linewidth less than ∼1 nm. In the initial stages of PEC etching, when the thin film is flat, characteristic voltammogram shapes are observed. At low photo-excitation rates, voltammograms are S-shaped, indicating the onset of a voltage-independent rate-limiting process associated with electron-hole-pair creation and/or annihilation. At high photo-excitation rates, voltammograms are superlinear in shape, indicating, for the voltage ranges studied here, a voltage-dependent rate-limiting process associated with surface electrochemical oxidation. As PEC etching proceeds, the thin film becomes rough at the nanoscale, and ultimately the self-limiting etch kinetics lead to an ensemble of nanoparticles. This change in InGaN film volume and morphology leads to a characteristic dependence of PEC etch rate on time: an incubation time, followed by a rise, then a peak, then a slow decay.

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The potential of ill-nitride laser diodes for solid-state lighting [Advantages of III-Nitride Laser Diodes in Solid-State Lighting]

Physica Status Solidi C

Wierer, Jonathan W.; Tsao, Jeffrey Y.

III-nitride laser diodes (LDs) are an interesting light source for solid-state lighting (SSL). Modelling of LDs is performed to reveal the potential advantages over traditionally used light-emitting diodes (LEDs). The first, and most notable, advantage is LDs have higher efficiency at higher currents when compared to LEDs. This is because Auger recombination that causes efficiency droop can no longer grow after laser threshold. Second, the same phosphor-converted methods used with LEDs can also be used with LDs to produce white light with similar color rendering and color temperature. Third, producing white light from direct emitters is equally challenging for both LEDs and LDs, with neither source having a direct advantage. Lastly, the LD emission is directional and can be more readily captured and focused, leading to the possibility of novel and more compact luminaires. These advantages make LDs a compelling source for future SSL.

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The Energy Frontier Research Center for Solid-State Lighting Science: Exploring New Materials Architectures and Light Emission Phenomena

Journal of Physical Chemistry C

Coltrin, Michael E.; Subramania, Ganapathi S.; Tsao, Jeffrey Y.; Wang, George T.; Wierer, Jonathan W.; Wright, Jeremy B.; Armstrong, Andrew A.; Brener, Igal B.; Chow, Weng W.; Crawford, Mary H.; Fischer, Arthur J.; Koleske, Daniel K.; Martin, James E.; Rohwer, Lauren E.

Abstract not provided.

Comparison between blue lasers and light-emitting diodes for future solid-state lighting: Comparison between blue lasers and light-emitting diodes

Laser & Photonics Reviews

Wierer, Jonathan W.; Tsao, Jeffrey Y.

Solid-state lighting (SSL) is now the most efficient source of high color quality white light ever created. Nevertheless, the blue InGaN light-emitting diodes (LEDs) that are the light engine of SSL still have significant performance limitations. Foremost among these is the decrease in efficiency at high input current densities widely known as “efficiency droop.” Efficiency droop limits input power densities, contrary to the desire to produce more photons per unit LED chip area and to make SSL more affordable. Pending a solution to efficiency droop, an alternative device could be a blue laser diode (LD). LDs, operated in stimulated emission, can have high efficiencies at much higher input power densities than LEDs can. In this article, LEDs and LDs for future SSL are explored by comparing: their current state-of-the-art input-power-density-dependent power-conversion efficiencies; potential improvements both in their peak power-conversion efficiencies and in the input power densities at which those efficiencies peak; and their economics for practical SSL.

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A case for Sandia investment in complex adaptive systems science and technology

Johnson, Curtis M.; Backus, George A.; Brown, Theresa J.; Colbaugh, Richard C.; Jones, Katherine A.; Tsao, Jeffrey Y.

This white paper makes a case for Sandia National Laboratories investments in complex adaptive systems science and technology (S&T) -- investments that could enable higher-value-added and more-robustly-engineered solutions to challenges of importance to Sandia's national security mission and to the nation. Complex adaptive systems are ubiquitous in Sandia's national security mission areas. We often ignore the adaptive complexity of these systems by narrowing our 'aperture of concern' to systems or subsystems with a limited range of function exposed to a limited range of environments over limited periods of time. But by widening our aperture of concern we could increase our impact considerably. To do so, the science and technology of complex adaptive systems must mature considerably. Despite an explosion of interest outside of Sandia, however, that science and technology is still in its youth. What has been missing is contact with real (rather than model) systems and real domain-area detail. With its center-of-gravity as an engineering laboratory, Sandia's has made considerable progress applying existing science and technology to real complex adaptive systems. It has focused much less, however, on advancing the science and technology itself. But its close contact with real systems and real domain-area detail represents a powerful strength with which to help complex adaptive systems science and technology mature. Sandia is thus both a prime beneficiary of, as well as potentially a prime contributor to, complex adaptive systems science and technology. Building a productive program in complex adaptive systems science and technology at Sandia will not be trivial, but a credible path can be envisioned: in the short run, continue to apply existing science and technology to real domain-area complex adaptive systems; in the medium run, jump-start the creation of new science and technology capability through Sandia's Laboratory Directed Research and Development program; and in the long run, inculcate an awareness at the Department of Energy of the importance of supporting complex adaptive systems science through its Office of Science.

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A brief history of Sandia National Laboratories and the Department of Energy%3CU%2B2019%3Es Office of Science : interplay between science, technology, and mission

Tsao, Jeffrey Y.; Simmons, J.A.; Collis, Samuel S.; McIlroy, Andrew M.

In 1957, Sandia National Laboratories (Sandia) initiated its first programs in fundamental science, in support of its primary nuclear weapons mission. In 1974, Sandia initiated programs in fundamental science supported by the Department of Energy's Office of Science (DOE-SC). These latter programs have grown to the point where, today in 2011, support of Sandia's programs in fundamental science is dominated by that Office. In comparison with Sandia's programs in technology and mission applications, however, Sandia's programs in fundamental science are small. Hence, Sandia's fundamental science has been strongly influenced by close interactions with technology and mission applications. In many instances, these interactions have been of great mutual benefit, with synergies akin to a positive 'Casimir's spiral' of progress. In this report, we review the history of Sandia's fundamental science programs supported by the Office of Science. We present: (a) a technical and budgetary snapshot of Sandia's current programs supported by the various suboffices within DOE-SC; (b) statistics of highly-cited articles supported by DOE-SC; (c) four case studies (ion-solid interactions, combustion science, compound semiconductors, advanced computing) with an emphasis on mutually beneficial interactions between science, technology, and mission; and (d) appendices with key memos and reminiscences related to fundamental science at Sandia.

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Solid-state lighting : the III-V Epi Killer App

Tsao, Jeffrey Y.

Throughout its history, lighting technology has made tremendous progress: the efficiency with which power is converted into usable light has increased 2.8 orders of magnitude over three centuries. This progress has, in turn, fueled large increases in the consumption of light and productivity of human society. In this talk, we review an emerging new technology, solid-state lighting: its frontier performance potential; the underlying advances in physics and materials that might enable this performance potential; the resulting energy consumption and human productivity benefits; and the impact on worldwide III-V epi manufacture.

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Results 1–100 of 122
Results 1–100 of 122