Experimental Observation of Vector Bound States in the Continuum

• DOI: 10.1002/adom.202203118
• Publication Date: 2023-03-24T08:12:54Z
• Authors: Huizhen Zhang; Weixuan Zhang; Shaohu Chen; Pengfei Duan; Junjie Li; Lei Shi; Jian Zi; Xiangdong Zhang
• Keywords: Coalescence (physics)

Abstract Bound states in the continuum (BICs) provide an important way for creating photonic devices reliant upon optical modes with high Q‐factors. However, current experimental implementations of BICs crystal (PhC) slabs only possess a certain polarization, which fundamentally restricts their use to surface‐enhanced applications assisted by scalar‐polarized near fields. In this work, vector PhC are theoretically designed and experimentally realized. theory, symmetry‐protected can be constructed tuning geometric parameters slab, where coalescence eigenfrequencies pair TE‐ TM‐like appears. It is found that homogeneous superchiral fields three orders magnitude larger than circular polarized lights achieved, quasi‐BICs. Furthermore, Si 3 N 4 fabricated band structures measured. shown polarizations coalesce each other at suitable value diameter array holes, indicating realization BICs. This work field ultrasensitive detections molecular chirality.