The Ohio State University

Abstract: 

Energy consumption in our society is increasing rapidly. A significant fraction of the energy is lost in the form of heat. In this talk we introduce solid-state devices that allow direct conversion of heat into electricity. We describe fundamental and practical limits of conventional thermoelectric power generation. Novel metal-semiconductor nanocomposites are developed where the heat and charge transport are modified at the atomic level. Theoretical calculation of the electronic transport taking into account quantum corrections due to superlattices and nanoparticle scattering is presented. Theory and experiment are compared in the case of rare-earth ErAs nanoparciles in InGaAlAs semiconductor matrix as well as in ZrN/ScN multilayer films. Potential to reach energy conversion efficiencies exceeding 15-20% is discussed. We also describe how similar principles can be used to make micro refrigerators on a chip and remove hot spots in integrated circuits. Recent calculations show that nanostructued SiGe material could be used to achieve on chip cooling by more than 20C and cooling power density exceeding 1kW/cm2.

Bio:

Ali Shakouri is a professor of electrical engineering at University of California Santa Cruz. He received his Ph.D. from California Institute of Technology in 1995. His current research is on nanoscale heat and current transport in semiconductor devices, high resolution thermal imaging, micro refrigerators on a chip and waste heat recovery. He is also working on a new sustainability curriculum in collaboration with colleagues in engineering and social sciences. He has initiated an international summer school on renewable energy sources in practice. He is the director of the Thermionic Energy Conversion center, a multi university research initiative aiming to improve direct thermal to electric energy conversion technologies. He is the author or co-author of more than 200 journal and conference papers. He received the Packard Fellowship in Science and Engineering in 1999, the NSF CAREER award in 2000 and the UCSC School of Engineering FIRST Professor Award in 2004.

The seminar will be held in E001 Scott Laboratory and hosted by Professor Bharat Bhushan.