标 题：Non-magnetic optical isolators: what works and what does not?
时 间：2019 年 11 月 12 日 14 : 30 - 16 : 30
地 点：南五楼 612 室
报告人：Jacob B. Khurgin 教授
美国物理学会（APS）和 美国光学学会（OSA）会士
邀请人：李德慧 教授
报告摘要：
Optical Isolator is a key component of photonic circuits and systems. An optical isolator requires non-reciprocal propagation i.e. breaking time inversion symmetry. Time symmetry cannot be broken in a linear optical system without magnetic field and/or gain and loss, hence all the practical isolators at this point are based on Faraday (magneto optic) effect which makes it difficult to develop isolators for planar integrated photonic circuits. Therefore, in recent years a strong effort has been mounted to develop non-magnetic isolators. A number of schemes had been proposed and demonstrated, such as devices with temporal modulation, acousto-optic and opto-mechanical isolators, various nonlinear schemes and parity time schemes with gain and loss.
In this talk we review performance characteristics of all these schemes and find them lacking any advantages in comparison to magnetic isolators. Most of the proposed schemes are severely limited in bandwidth and require high power consumption. Moreover, often they are not true optical isolators but are “optical diodes” in the sense that they do not offer full isolation.
We then make a case for the optical isolator based on second and third order nonlinearities that have good isolation and high dynamic range and offer detailed analysis of this exciting family of devices. Initial “proof of concept” experimental results will also be presented.
报告人介绍:
Jacob B. Khurgin 教授，美国物理学会（APS）和美国光学学会（OSA）会士，分别于1977年和1979年在俄罗斯圣彼得堡的精细机械和光学研究所获得了光学学士和硕士学位，1987年获得纽约大学电子物理学博士学位，1988年加入约翰霍普金斯大学。Jacob B. Khurgin 教授致力于光学和固体电子学交叉领域的研究，包括半导体纳米结构光学、非线性光学器件、激光、光通信、微波光子学和凝聚态物理等方向。Jacob B. Khurgin 教授曾担任60多次学术会议的技术项目委员会成员和多所大学的客座教授，包括普林斯顿大学、加州大学洛杉矶分校、布朗大学、苏黎世联邦理工学院和巴黎高等师范学院等。迄今为止，Jacob B. Khurgin 教授已经发表了文章340多篇和授权专利约40项，总引用次数超过12000次，H-因子58。担任著名光学杂志 Optica 的副主编和多种期刊审稿人，包括《科学》、《自然》和《国家科学院学报》等。
