Optik Pub Date : 2021-06-15 , DOI: 10.1016/j.ijleo.2021.167452 Zhang Lei , Li Jiu-sheng
Owing to the eigenstates of orbital angular momentum (OAM) are infinite and orthogonal to each other, OAM can improve communication capacity infinitely. In this paper, we propose a terahertz vortex beam generator on transmissive metasurfaces. When the y-polarized terahertz wave illuminates vertically to the metasurface along the -z direction, the proposed metasurface generates terahertz vortex beams with topological charges l = ±1, l = ±2 and l = ±3 at the frequency ranging from 0.3 THz to 0.9 THz. We study the far-field radiation, electric field phase, amplitude characteristics, and mode purity with different topological charges. The simulation results are in good agreements with the theoretical predictions.
中文翻译:
基于透射超表面在太赫兹区域工作的涡流发生器
由于轨道角动量(OAM)的本征态是无限的并且相互正交,OAM可以无限地提高通信容量。在本文中,我们提出了一种在透射超表面上的太赫兹涡旋光束发生器。当y极化太赫兹波沿 - z方向垂直照射超表面时,所提出的超表面会产生具有拓扑电荷l = ±1、l = ±2 和l 的太赫兹涡旋光束 = ±3,频率范围为 0.3 THz 至 0.9 THz。我们研究了不同拓扑电荷的远场辐射、电场相位、振幅特性和模式纯度。模拟结果与理论预测非常吻合。