Dual-polarization two-dimensional valley photonic crystals

作     者：Xin-Tao He Jian-Wei Liu Fu-Long Shi Ke Shen Wen-Jie Chen Xiao-Dong Chen Jian-Wen Dong 

作者机构：School of PhysicsState Key Laboratory of Optoelectronic Materials and TechnologiesSun Yat-sen UniversityGuangzhou510275China 

出 版 物：《Science China(Physics,Mechanics & Astronomy)》 (中国科学：物理学、力学、天文学（英文版）)

年 卷 期：2022年第65卷第8期

页      面：102-109页

核心收录：

学科分类：08[工学] 0705[理学-地理学] 0804[工学-仪器科学与技术] 0803[工学-光学工程] 0701[理学-数学] 

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.12074443,62035016,and 11904421) Guangdong Basic and Applied Basic Research Foundation(Grant No.2019B151502036) Guangzhou Science,Technology and Innovation Commission(Grant Nos.201904010223,202002030322,and 202102020693) the Fundamental Research Funds for the Central Universities(Grant Nos.20lgzd29,20lgjc05,and 2021qntd27)。 

主　　题：topological photonics valley photonic crystals polarization 

摘      要：The recent realization of valley physics in photonic systems has enriched the topological phases of light with protected edge modes and shown applications in designing high-performance photonic devices. However, the widely reported valley Hall effect of light in two-dimensional systems is limited to one single polarization. Here, we present dual-polarization two-dimensional valley photonic crystals by simultaneously opening two frequency accidental degenerate Dirac cones. Two band gaps with different polarizations are characterized by opposite-valley Chern numbers, which are confirmed by the opposite-phase vortex distributions of bulk modes and opposite Berry curvatures. This situation results in the polarization-dependent refraction of bulk and edge modes, which locate in opposite valleys. The polarization-independent topological valley transport is also demonstrated. Our work shows the flexible control of light in topological photonic systems with a polarization degree of freedom and has applications in polarization multiplexing photonic devices.