中国物理B ›› 2023, Vol. 32 ›› Issue (1): 14201-014201.doi: 10.1088/1674-1056/ac728d

• • 上一篇    下一篇

Evolution of polarization singularities accompanied by avoided crossing in plasmonic system

Yi-Xiao Peng(彭一啸)1, Qian-Ju Song(宋前举)2,†, Peng Hu(胡鹏)1, Da-Jian Cui(崔大健)3, Hong Xiang(向红)1,‡, and De-Zhuan Han(韩德专)1,§   

  1. 1 Chongqing University, Chongqing 400044, China;
    2 School of Science, Southwest University of Science and Technology, Mianyang 621010, China;
    3 Chongqing Key Laboratory of Core Optoelectronic Devices for Quantum Communication, Chongqing Optoelectronics Research Institute, Chongqing 400060, China
  • 收稿日期:2022-02-19 修回日期:2022-05-20 接受日期:2022-05-24 出版日期:2022-12-08 发布日期:2022-12-23
  • 通讯作者: Qian-Ju Song, Hong Xiang, De-Zhuan Han E-mail:qjsong@cqu.edu.cn;xhong@cqu.edu.cn;dzhan@cqu.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 12074049 and 12047564), the Fundamental Research Funds for the Central Universities, China (Grant Nos. 2020CDJQY-Z006 and 2020CDJQYZ003), and the Research Foundation of SWUST (Grant No. 21zx7141).

Evolution of polarization singularities accompanied by avoided crossing in plasmonic system

Yi-Xiao Peng(彭一啸)1, Qian-Ju Song(宋前举)2,†, Peng Hu(胡鹏)1, Da-Jian Cui(崔大健)3, Hong Xiang(向红)1,‡, and De-Zhuan Han(韩德专)1,§   

  1. 1 Chongqing University, Chongqing 400044, China;
    2 School of Science, Southwest University of Science and Technology, Mianyang 621010, China;
    3 Chongqing Key Laboratory of Core Optoelectronic Devices for Quantum Communication, Chongqing Optoelectronics Research Institute, Chongqing 400060, China
  • Received:2022-02-19 Revised:2022-05-20 Accepted:2022-05-24 Online:2022-12-08 Published:2022-12-23
  • Contact: Qian-Ju Song, Hong Xiang, De-Zhuan Han E-mail:qjsong@cqu.edu.cn;xhong@cqu.edu.cn;dzhan@cqu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 12074049 and 12047564), the Fundamental Research Funds for the Central Universities, China (Grant Nos. 2020CDJQY-Z006 and 2020CDJQYZ003), and the Research Foundation of SWUST (Grant No. 21zx7141).

摘要: The evolution of polarization singularities supported in a one-dimensional periodic plasmonic system is studied. The lateral inversion symmetry of the system, which breaks the in-plane inversion symmetry and up-down mirror symmetry simultaneously, yields abundant polarization states. A complete evolution process with geometry for the polarization states is traced. In the evolution, circularly polarized points (C points) can stem from 3 different processes. In addition to the previously reported processes occurring in an isolated band, a new type of C point appearing in two bands simultaneously due to the avoided band crossing, is observed. Unlike the dielectric system with a similar structure which only supports at-$\varGamma$ bound states in the continuum (BICs), accidental BICs off the $\varGamma$ point are realized in this plasmonic system. This work provides a new scheme of polarization manipulation for the plasmonic systems.

关键词: polarization singularities, topological charge, avoided crossing, inversion symmetry

Abstract: The evolution of polarization singularities supported in a one-dimensional periodic plasmonic system is studied. The lateral inversion symmetry of the system, which breaks the in-plane inversion symmetry and up-down mirror symmetry simultaneously, yields abundant polarization states. A complete evolution process with geometry for the polarization states is traced. In the evolution, circularly polarized points (C points) can stem from 3 different processes. In addition to the previously reported processes occurring in an isolated band, a new type of C point appearing in two bands simultaneously due to the avoided band crossing, is observed. Unlike the dielectric system with a similar structure which only supports at-$\varGamma$ bound states in the continuum (BICs), accidental BICs off the $\varGamma$ point are realized in this plasmonic system. This work provides a new scheme of polarization manipulation for the plasmonic systems.

Key words: polarization singularities, topological charge, avoided crossing, inversion symmetry

中图分类号:  (Wave optics)

  • 42.25.-p
73.20.Mf (Collective excitations (including excitons, polarons, plasmons and other charge-density excitations)) 42.79.Dj (Gratings) 78.67.Pt (Multilayers; superlattices; photonic structures; metamaterials)