Egorov Yuriy, Rubass Alexander
J Opt Soc Am A Opt Image Sci Vis. 2024 Jun 1;41(6):1000-1008. doi: 10.1364/JOSAA.523057.
The work shows that in linearly polarized Laguerre-Gaussian beams passing through an anisotropic medium at an angle to the optical axis of the crystal, the distribution of optical vortices is devoid of axial symmetry. It is shown that the trajectories of movement of polarization singularities in the plane of the Laguerre-Gauss beam are different for different cases of input linear polarization at angles =±45 and there is an exchange of optical vortices, provided that the sign of the topological charge is preserved. It is shown that when the axis of an anisotropic medium is tilted, the movement of optical vortices occurs, accompanied by topological reactions of creation, destruction, or displacement of optical vortices to the periphery of the beam. It is characteristic that at angles of inclination by linear polarization =+45, topological reactions of creation and annihilation occur, and at angles =-45, topological reactions of displacement of optical vortices to the periphery of the beam occur.
该研究表明,当线偏振拉盖尔 - 高斯光束以一定角度穿过与晶体光轴成一定角度的各向异性介质时,光学涡旋的分布缺乏轴对称性。结果表明,对于输入线性偏振角度为±45°的不同情况,拉盖尔 - 高斯光束平面中偏振奇点的移动轨迹不同,并且只要拓扑电荷的符号保持不变,就会发生光学涡旋的交换。研究表明,当各向异性介质的轴倾斜时,会发生光学涡旋的移动,同时伴随着光学涡旋的产生、破坏或向光束周边位移的拓扑反应。其特点是,当线性偏振倾斜角度为 +45°时,会发生产生和湮灭的拓扑反应;当角度为 -45°时,会发生光学涡旋向光束周边位移的拓扑反应。