Time: 10:00am, 26th Nov, 2009( Thursday)
Location: Conference Room 440, the 3rd Academic Building, Yuquan Campus, Zhejiang University
Nanostructured Materials and Optics: Enabling a New Era of Optoelectronic Technologies
Connie J. Chang-Hasnain
Dept. of Electrical Engineering and Computer Science
University of California, Berkeley, CA 94720
email: cch@eecs.berkeley.edu
Abstract
There are intense interests in semiconductor structures with dimensions at the two ends of the nanometer regime. Materials with size on the order of a few nanometers are critical because their physical properties may be altered by its dimensions. In particular, they offer a tremendous opportunity to engineer properties of optoelectronic materials. On the other hand, materials that have sub-optical-wavelength dimensions are of enormous interests because they open up a new window to re-examine the wave guiding properties. In this talk, I will provide a brief overview of our activities in these areas.
I will discuss the synthesis and characteristics of III-V compound nanoneedles that are monolithically grown on Si and sapphire despite of a very large lattice mismatches, 4% and 33%, respectively. The structures show excellent crystalline and optical quality. The nanoneedles are promising for ultrahigh gain avalanche photo detectors, low threshold lasers on Si and high efficiency solar cells. This new material enables the opportunities of making highly efficient optoelectronic devices on Si. They will find applications for optical interconnects, field emission tips, AFM probe tips and atto-liter liquid delivery.
For the hundred-nm regime structures, we recently discovered a novel high index contrast subwavelength grating (HCG) structure, which showed an unprecedented effects on optical wave guiding and reflection properties. I will discuss new integrated optics using HCG as a platform. The HCG grating brings guided-wave optics to a totally untrespassed regime and will find many useful applications in lasers, filters, waveguides, bio/chemical and gas sensors and detectors.
Biography Connie Chang-Hasnain is the John R. Whinnery Chair Professor in the Electrical Engineering and Computer Sciences Department at the University of California, Berkeley. She received a B.S. from the University of California, Davis (1982), and M.S. (1984) and Ph.D. (1987) degrees from the University of California, Berkeley, all in electrical engineering and computer sciences. Prior to joining the Berkeley faculty, Dr. Chang-Hasnain was a member of the technical staff at Bellcore (1987–1992) and an Assistant Professor of Electrical Engineering at Stanford University (1992–1996). She currently serves as Chair of the Nanoscale Science and Engineering (NSE) Graduate Group and is a Chang Jiang Scholar Endowed Chair at Tsinghua University from the Peoples Republic of China, Ministry of Education 2009.
Prof. Chang-Hasnain’s research interests have been in vertical cavity surface emitting lasers, MEMS tunable optoelectronic devices and nanostructured materials and nano-optoelectronic devices. Prof. Chang-Hasnain co-authored over 400 research papers in technical journals and conferences, seven book chapters and 36 patents.
She was named a Presidential Faculty Fellow, an NSF National Young Investigator, a Packard Fellow, a Sloan Research Fellow, and Outstanding Young Electrical Engineer of the Year by Eta Kappa Nu. She received numerous awards for her research contributions, including the 1994 IEEE LEOS Distinguished Lecturer Award, 2000 Curtis W. McGraw Research Award from the American Society of Engineering Education, 2003 IEEE LEOS William Streifer Scientific Achievement Award, 2005 Gilbreth Lecturer Award from National Academy of Engineering, 2007 Nick Holonyak Jr Award from the Optical Society of America, 2008 National Security Science and Engineering Faculty Fellowship, 2009 Guggenheim Memorial Fellowship, and 2009 Humboldt Research Award from the Alexander von Humboldt Stiftung Foundation. Prof. Chang-Hasnain is a Fellow of the IEEE, OSA and IEE. She is an Honorary Member of A.F. Ioffe Institute. Since 2007, she is the Editor-in-Chief of the Journal of Lightwave Technology.