Confinement and manipulation of photons using microcavities have triggered intense research interest in both fundamental and applied photonics for more than one decade. Prominent examples are ultrahigh-Q whispering gallery microcavities which confine photons by means of continuous total internal reflection along a curved and smooth surface. The long photon lifetime, strong field confinement, and in-plane emission characteristics make them promising candidates for enhancing light-matter interactions on a chip. In the first part of this talk, I will introduce some representative photonics applications of ultrahigh-Q microcavities, such as cavity quantum electrodynamics, cavity optomechanics, ultralow-threshold microlasing (microcomb), and highly sensitive optical sensing. In the second part, I will focus on the single-nanoparticle detection by using whispering gallery microcavities, which is highly desirable for applications in various fields, such as in early-stage diagnosis of human diseases and in environmental monitoring.

   北京大学研究员，博士生导师。研究方向为微纳光学与量子光学，主要从事高品质因子光学微腔的实验和理论研究。近年在PNAS，Phys. Rev. Lett.，Advanced Materials和Laser & Photonics Reviews 等国际主流杂志发表研究论文100余篇，他引2000余次，h因子29。研究成果5 次入选期刊封面，20余次被Phys.org、Optics & Photonics News和Materials Views等国际著名科技媒体亮点评述，入选了“2010年度中国光学重要成果”、“2014年度中国高校十大科技进展”和“北京市自然科学基金资助项目优秀成果汇编”等。担任国际学术刊物《Photonics Research》编委。