Rotation-induced plasmonic chiral quasi-bound states in the continuum  

作　　者：CHUNHUA QIN YADONG DENG TIANSHUO LYU CHAO MENG SÖREN IM SANDE SERGEY I.BOZHEVOLNYI JINHUI SHI FEI DING 

机构地区：[1]Key Laboratory of In-Fiber Integrated Optics of Ministry of Education and Key Laboratory of Photonic Materials and Devices Physics for Oceanic Applications of Ministry of Industry and Information Technology,College of Physics and Optoelectronic Engineering,Harbin Engineering University,Harbin 150001,China [2]Centre for Nano Optics,University of Southern Denmark,DK-5230 Odense,Denmark

出　　处：《Photonics Research》2025年第1期69-79,共11页光子学研究(英文版)

基　　金：National Natural Science Foundation of China(62275061);Villum Fonden(37372,50343);Danmarks Frie Forskningsfond(1134-00010B);China Scholarship Council(202108330079).

摘　　要：Nanoscale light manipulation using plasmonic metasurfaces has emerged as a frontier in photonic research,offering strongly enhanced light-matter interactions with potential applications in sensing,communications,and quantum optics.Here,we unveil the realization and control of chiral quasi-bound states in the continuum(quasi-BICs)by judiciously rotating one of the paired plasmonic bricks and thereby influencing structural asymmetry.By precisely controlling the rotation angle,we enable continuous modulation of the radiation loss in quasi-BICs and transition from a perfect half-wave plate to a good absorber for the left-handed circularly polarized light.This transformation leverages the intrinsic chirality with moderately high circular dichroism of∼0.35 in both simulation and experimental observations,manifesting unprecedented control over the chiral light within subwavelength scales.Theoretical modeling and numerical simulations complement our experimental findings,offering deep insights into underlying mechanisms and the role of symmetry breaking in realizing chiral quasi-BICs.The observed phenomena open new pathways for developing ultra-compact chiral photonic devices with tailored optical properties,including highly sensitive chiral biosensors,circular dichroism spectroscopy,and chiral flat optical components for information processing.

关 键 词：QUASI CHIRAL CIRCULAR 

分 类 号：O53[理学—等离子体物理]