- Tarr-Coyne Professor of Applied Physics and of Electrical Engineering
- Participant, Nanoscale Science and Engineering Center
Our ability to modulate the materials at nanometer length scales allows us to modify the electronic or photonic energy states of that material, thus transforming their properties and applications.
For example, modulating the dielectric constant of materials like GaAs, GaN or diamond, at the length scale of a wavelength, can produce exquisitely tuned optical filters, waveguides or a means to slow or store light itself. We can engineer the number and signature energies of the optical states of such ‘nanophotonic’ structures, and match them to optical sources, such as quantum dots, quantum wells or color centers in diamond.
The results so far include lasers with record low threshold values, triggered single photon sources, enhanced extraction of light from InGaN light emitting diodes, and new, coupled light-matter states. The implications are far-ranging: from energy-efficient optical sources to exploration of quantum information processing.
Sculpting nanostructures from solid state materials requires tools and processes that have high spatial precision, but which themselves introduce the minimum damage to the material.
Our group has focused on developing such techniques, while at the same time exploring the ‘bottom-up’ formation of heterogeneous materials from nanoscale building blocks. Creating new materials from composites of semiconducting, insulating and metallic nanoparticles allows the formation of truly three-dimensional structures that can display improved functionality, such as broad, engineered optical absorption, or distributed carrier collection for a large area, efficient optical absorber.
Important issues here are related to the nature of the interfaces between the nanoparticles, and controlling the ‘hierarchical’ architecture that determines the positions of the components. We have explored a variety of techniques, including a method of templating materials on a biological structure (virus), where the materials-specific linkers are specially identified peptides. We have used these to form metal-semiconductor hybrid materials.
Positions & Employment
Harvard School of Engineering and Applied Sciences
- January 2009-Present: Gordon McKay Professor of Applied Physics and Electrical Engineering
University of California at Santa Barbara, College of Engineering
- Dec. 2000–Jan. 2009: Scientific Co-Director California Nanosystems Institute
- July 2000-June 2001: Director, Institute for Quantum Engineering, Science and Technology (iQUEST)
- July 1994–July 2000: Director, Center for Quantized Electronic Structures (QUEST, an NSF Science and Technology Center)
- March 1994–June 2001: Director, Santa Barbara component of NSF National Nanofabrication Users Network
- July 1992-Aug. 1994: Chair, Department of Electrical and Computer Engineering
- 1989-July 1992: Vice-Chair Department of Electrical and Computer Engineering
- 1984-2009: Professor, Electrical and Computer Engineering
- 1984-1987: Associate Director, Center for Robotic Systems in Microelectronics (an NSF Engineering Research Center)
- 1981-1984: Supervisor, VLSI Patterning Processes
- 1975-1981: Member of Technical Staff
Other Experience & Professional Membership
- Elected National Academy of Sciences, 2008
- Elected Academica Sinica, Taiwan, 2004
- Elected National Academy of Engineering, 2002
- Fellow of the AAAS, 1998
- Fellow of the APS, 1995
- Fellow of the IEEE, 1994
- Named NSF Distinguished Teaching Scholar, 2005
- Co-recipient, Outstanding Faculty Teacher, Dept. of ECE, 2005
- UCSB Faculty Research Lecturer, 2005
- AAAS Lifetime Mentor Award, 2000
- UCSB Academic Senate Distinguished Teaching Award, 1999
- Honorary Doctor of Engineering, University of Glasgow, June 1995
- Tau Beta Pi Outstanding Faculty Teacher in Dept. of ECE, 1989-90