时间：2014年12月26日（星期五）下午14：30
地点：材料科学与工程学院光通信材料研究所302会议室

报告摘要：
       Optical sensing with ultrahigh sensitivity of single nanoscale objects is strongly desirable for applications in various fields, such as in early-stage diagnosis of human diseases and in environmental monitoring. High-Q microcavities, which can significantly enhance light-matter interactions, provide ideal platforms for label-free, ultrasensitive detection of single nano-objects. In this talk, we report the experimental demonstration of single nanoparticle detection using either resonance mode broadening or microcavity Raman laser splitting. For the latter, by monitoring the step changes in beat frequency of the two split Raman mode lasing, detection of single 20-nm-radius nanoparticles is realized in an aqueous environment. Since Raman scattering occurs in most materials under practically any pump wavelength, this split-mode Raman laser provides a more practical sensing platform.

附报告人简介
       Dr. Yun-Feng Xiao received the B.S. and Ph.D. degrees in physics from University of Science and Technology of China in 2002 and 2007, respectively. After a postdoctoral research at Washington University in St. Louis, he joined the faculty of Peking University in 2009, and was promoted to Associate Professor with tenure in 2014. During the past few years, he was awarded the Excellent Young Scientist by National Natural Science Foundation of China (NSFC) in 2012, The Rao Yutai First Prize in Fundamental Optics in 2013. His research interests lie in the fields of whispering-gallery microcavity optics and photonics. He has authored or co-authored more than 80 refereed journal papers with over 1500 citations, and has delivered over 30 invited talks/seminars in international/national conferences.