中国物理B ›› 2023, Vol. 32 ›› Issue (11): 114213-114213.doi: 10.1088/1674-1056/ad0621

所属专题: SPECIAL TOPIC — Celebrating the 100th Anniversary of Physics Discipline of Northwest University

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Topological states switching and group velocity control in two-dimensional non-reciprocal Hermitian photonic lattice

Yu Lin(林宇), Yuandan Wang(王元旦), Junhao Yang(杨俊豪), Yixuan Fu(符艺萱), and Xinyuan Qi(齐新元)   

  1. School of Physics, Northwest University, Xi'an 710127, China
  • 收稿日期:2023-06-30 修回日期:2023-10-23 接受日期:2023-10-24 出版日期:2023-10-16 发布日期:2023-11-03
  • 通讯作者: Xinyuan Qi E-mail:qixycn@nwu.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 12174307).

Topological states switching and group velocity control in two-dimensional non-reciprocal Hermitian photonic lattice

Yu Lin(林宇), Yuandan Wang(王元旦), Junhao Yang(杨俊豪), Yixuan Fu(符艺萱), and Xinyuan Qi(齐新元)   

  1. School of Physics, Northwest University, Xi'an 710127, China
  • Received:2023-06-30 Revised:2023-10-23 Accepted:2023-10-24 Online:2023-10-16 Published:2023-11-03
  • Contact: Xinyuan Qi E-mail:qixycn@nwu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 12174307).

摘要: We proposed a model with non reciprocal coupling coefficients, in which the imaginary parts γ indicate the phase delay or exceed term. The distributions of band structure and the group velocity are both characterized as a function of the coupling. we studied the system's topological states and group velocity control. The results show that the movement and breaking of Dirac points exist in the energy band of the system. By changing the coupling coefficients, the conversion between any topological states corresponds to different Chern number. Topological edge states exist in topological non-trivial systems that correspond to the two different Chern numbers. Besides, it is also found that both the coupling coefficient and the wave vector can cause the oscillation of the pulse group velocity. At the same time, the topological state can suppress the amplitude of the group velocity profiles. Our findings enrich the theory of light wave manipulation in high-dimensional photonic lattices and provide a novel view for realizing linear localization and group velocity regulation of light waves, which has potential application in high-speed optical communication and quantum information fields.

关键词: Dirac point, imaginary coupling, Chern number, group velocity

Abstract: We proposed a model with non reciprocal coupling coefficients, in which the imaginary parts γ indicate the phase delay or exceed term. The distributions of band structure and the group velocity are both characterized as a function of the coupling. we studied the system's topological states and group velocity control. The results show that the movement and breaking of Dirac points exist in the energy band of the system. By changing the coupling coefficients, the conversion between any topological states corresponds to different Chern number. Topological edge states exist in topological non-trivial systems that correspond to the two different Chern numbers. Besides, it is also found that both the coupling coefficient and the wave vector can cause the oscillation of the pulse group velocity. At the same time, the topological state can suppress the amplitude of the group velocity profiles. Our findings enrich the theory of light wave manipulation in high-dimensional photonic lattices and provide a novel view for realizing linear localization and group velocity regulation of light waves, which has potential application in high-speed optical communication and quantum information fields.

Key words: Dirac point, imaginary coupling, Chern number, group velocity

中图分类号:  (Photonic bandgap materials)

  • 42.70.Qs
03.65.Vf (Phases: geometric; dynamic or topological) 42.79.Gn (Optical waveguides and couplers)