题目：Quantum metrology with nonlinear quantum interferometers
报告人：区泽宇 教授（美国Indiana-Purdue大学）
摘要：
Interferometers usually consist of linear elements such as beam splitters for wave splitting and recombination. These interferometers are widely used for precision measurement. Their sensitivity for phase measurement is limited by the shot noise, which can be suppressed with squeezed states of light. Here, we study a new type of interferometer in which the beam splitting and recombination elements are nonlinear devices. We demonstrate that the phase signal is enhanced while the noise is kept at near vacuum level, thus improving the signal-to-noise ratio compared to a traditional linear interferometer and leading to phase measurement sensitivity beyond the shot noise limit. Combined with squeezed state technique for shot noise suppression, this interferometer promises further improvement in sensitivity. Furthermore, the nonlinear nature of this interferometer can be used to couple a variety of different waves and form new types of hybrid interferometers, opening a door for many applications in metrology.
简介：
区泽宇教授在1984年毕业于北京大学物理系，于1990年在Rochester大学获得博士学位，1990-1992年在加州理工学院做博士后。现任Indiana Purdue大学物理系教授。他在量子光学研究领域有突出的贡献：发明了Hong-Ou-Mandel干涉仪，进行了Bell不等式的验证、EPR佯谬的演示、多光子态的产生等等。已发表文章90多篇，其中PRL有16篇，它引3000多次，其中单篇1200次。著有专著一部。邀请报告70多次。
时间：2013年6月3日（星期一）上午9：00
地点：中科院物理研究所M楼249会议室
联系人：吴令安 研究员（Tel：826489334）
金奎娟 研究员（Tel：82648099）
主办单位：中国科学院光物理重点实验室
