|
Arbitrary order exceptional point induced by photonic spin–orbit interaction in coupled resonators
点击次数：
论文类型：期刊论文
发表刊物：Nature Comm
所属单位：光电学院，国家光电研究中心
刊物所在地：美国
学科门类：工学
项目来源：自然科学基金
文献类型：J
卷号：832
期号：10
页面范围：1-10
关键字：无
DOI码：10.1038/s41467-019-08826-6
发表时间：2019-02-19
教研室：c716
摘要：Many novel properties of non-Hermitian systems are found at or near the exceptional points—branch points of complex energy surfaces at which eigenvalues and eigenvectors coalesce. In particular, higher-order exceptional points can result in optical structures that are ultrasensitive to external perturbations. Here we show that an arbitrary order exceptional point can be achieved in a simple system consisting of identical resonators placed near a waveguide. Unidirectional coupling between any two chiral dipolar states of the resonators mediated by the waveguide mode leads to the exceptional point, which is protected by the transverse spin–momentum locking of the guided wave and is independent of the positions of the resonators. Various analytic response functions of the resonators at the exceptional points are experimentally manifested in the microwave regime. The enhancement of sensitivity to external perturbations near the exceptional point is also numerically and analytically demonstrated.
备注：无