光电化学系列学术报告（三十七）2011-9-5

 报告题目：Hot Electrons and Hot Plasmons for Photovoltaics

 报告人：Prof. David J. Norris

                 Optical Materials Engineering Laboratory, ETH Zurich, Zurich Switzerland

 时间：2011年9月5日（星期一） 下午 16:30—17:30

地点：物理所B 楼404 会议室

报告摘要：

In this talk, Prof. Norris will discuss two recently observed phenomena with implications for photovoltaic devices. First, it is well known that conventional silicon solar cells lose a significant fraction of their absorbed energy when electrons are excited high into the conduction band cool to the band edge. Although colloidal semiconductor nanocrystals (or quantum dots) had been proposed as a route to slow down this cooling so the excess energy of these hot electrons could be captured, no experiments had yet demonstrated this effect. He will describe recent experiments that show the first step of this process — extraction of hot electrons from PbSe quantum dots. Second, he will discuss the thermal emission of periodically structured metals. In particular, we examine simple metallic films with surfaces that are patterned with a series of circular concentric grooves (a bull’s eye pattern). Due to thermal excitation of surface plasmons, a single beam of light can be emitted from these films in the normal direction that is amazingly narrow, both in terms of its spectrum and its angular divergence. Thus, metallic films can generate highly directional beams of light by a simple thermal process. Finally, he will discuss a general and simple route to fabricate such films that also has implications for other plasmonic approaches to solar cells.

报告人介绍：

David J. Norris is a Professor of Materials Engineering at ETH Zürich and Director of Optical Materials Engineering Laboratory in Department of Mechanical and Process Engineering. He received his B.S. from University of Chicago in 1990 and Ph.D. at MIT in 1995. After a National Science Foundation postdoctoral Fellowship at University of California, San Diego, he joined the NEC Research Institute in Princeton in 1997. In 2001, he moved to the University of Minnesota as an Associate Professor, and was a Professor In 2006. He was Director of Graduate Studies in Chemical Engineering from 2004 to 2010. In 2010, he moved to ETH Zürich as full professor. Prof. Norris’s main research focuses on semiconductor Nanocrystals and thermal Plasmonics. Applications include photovoltaic and thermophotovoltaic solar cells, respectively. Prof. Norris is a Fellow of the American Physical Society, the American Association for the Advancement of Science. He also served as editor for Photonics and Nanostructures and a member of the editorial board for Chemistry of Materials and Advanced Functional Materials. He has published over 80 research papers, including Nature, Science, Phys. Rew. Lett., Nature Mater., Adv. Mater. etc. and applied 6 patents.

Norris教授参观实验室