Manifestation of super chiral exceptional points in a plasmonic metasurface  

作　　者：HAOJIE LI GUOXIA YANG ANWEN JIANG MIN NI QIANWEN JIA FENGZHAO CAO JIAYI ZHANG BOKUN LYU DAHE LIU JINWEI SHI 

机构地区：[1]Applied Optics Beijing Area Major Laboratory and Key Laboratory of Multiscale Spin Physics,Ministry of Education,School of Physics and Astronomy,Beijing Normal University,Beijing 100875,China

出　　处：《Photonics Research》2024年第12期2863-2872,共10页光子学研究(英文版)

基　　金：National Natural Science Foundation of China(12174031,91950108).

摘　　要：The exceptional point(EP),a degenerate point within non-Hermitian parametric space,has attracted considerable attention,especially for its chiral responses.However,achieving ideal circular dichroism(CD)remains challenging due to the existence of parallel components at the EP.Here,we delve into the theoretical condition required to attain a zero-transmission parallel component.This condition,together with the chiral EP condition,leads to a point characterized by near-unity CD,termed the super chiral EP(SCEP).To illustrate our theoretical framework,we introduce a parity-time symmetric metasurface with gain and loss.The observation of SCEP is demonstrated by tuning both the coupling strength and gain–loss ratio.Furthermore,we explore distinctive properties of SCEP,including phase flip and unidirectional invisibility.Leveraging SCEP and the topological phase transition point,we achieve polarization states across the entire Poincarésurface.This work opens avenues for potential applications in polarizing optical elements,holography,logic gates,chiral molecular detection,ultrasensitive sensing,and polarization-sensitive imaging.

关 键 词：POINCARÉ SURFACE CHIRAL 

分 类 号：O53[理学—等离子体物理] O441.4[理学—物理]