• Advanced Photonics Nexus
  • Vol. 1, Issue 2, 026003 (2022)
Bing-Yan Wei1、2、†,*, Yuan Zhang3, Haozhe Xiong1、2, Sheng Liu1、2、*, Peng Li1、2, Dandan Wen1、2, and Jianlin Zhao1、2、*
Author Affiliations
  • 1Northwestern Polytechnical University, School of Physical Science and Technology, Shaanxi Key Laboratory of Optical Information Technology, Xi’an, China
  • 2Ministry of Industry and Information Technology, Key Laboratory of Light Field Manipulation and Information Acquisition, Xi’an, China
  • 3Chinese Flight Test Establishment, Xi’an, China
  • show less
    DOI: 10.1117/1.APN.1.2.026003 Cite this Article Set citation alerts
    Bing-Yan Wei, Yuan Zhang, Haozhe Xiong, Sheng Liu, Peng Li, Dandan Wen, Jianlin Zhao. Janus vortex beams realized via liquid crystal Pancharatnam–Berry phase elements[J]. Advanced Photonics Nexus, 2022, 1(2): 026003 Copy Citation Text show less

    Abstract

    Emerging as a family of waves, Janus waves are known to have “real” and “virtual” components under inversion of the propagation direction. Although tremendous interest has been evoked in vortex beams featuring spiral wavefronts, little research has been devoted to the vortex beam embedded Janus waves, i.e., Janus vortex beams. We propose a liquid crystal (LC) Pancharatnam–Berry (PB) phase element to demonstrate the realization of the Janus vortex beams and the modulation of the associated orbit angular momentum (OAM) and spin angular momentum (SAM). The generated Janus vortex beams show opposite OAM and SAM states at two distinct foci, revealing a spin-orbit interaction during propagation enabled by the LC PB phase element, which may play special roles in applications such as optical encryption and decryption. Other merits like reconfigurability and flexible switching between Janus vortex beams and autofocusing or autodefocusing vortex beams additionally increase the degree of freedom of manipulating vortex beams. This work provides a platform for tailoring complex structured light and may enrich the applications of vortex beams in classical and quantum optics.
    φ=βr3+2πr/d+mθ,

    View in Article

    α=φ/2=βr3/2+πr/d+qθ,

    View in Article

    M=[cos2αsin2αsin2αcos2α].

    View in Article

    Ein=E0[cosθinsinθin]=E02(eiθin|L+eiθin|R),

    View in Article

    Eout=M·Ein=E02(ei2αeiθin|R+ei2αeiθin|L)=E02[ei(βr3+2πr/d)eimθeiθin|R+ei(βr3+2πr/d)eimθeiθin|L].

    View in Article

    {1z1+1zCAB=1fL1z2+1zCAB*=1fL,

    View in Article

    fCAB=48fL14λ2βπw3d,

    View in Article

    Bing-Yan Wei, Yuan Zhang, Haozhe Xiong, Sheng Liu, Peng Li, Dandan Wen, Jianlin Zhao. Janus vortex beams realized via liquid crystal Pancharatnam–Berry phase elements[J]. Advanced Photonics Nexus, 2022, 1(2): 026003
    Download Citation