Asymmetric Transmission of OAM Vortex Waves by Cylindrical Janus Metasurface
Le Jiang, Shixing Yu, Na Kou
Abstract
In this letter, the asymmetric transmission of orbital angular momentum orbital angular momentum (OAM) vortex waves is realized by a cylindrical Janus metasurface. It can generate orbital angular momentum vortex waves with different modes at two opposite propagation directions. Three-layered split rings structure with sequentially 45° rotation is designed to realize the asymmetric transmission and phase modulation at the same time, which can provide one linear polarization conversion of EM wave and a continuous 360° transmission phase shift. We also propose a unit cell distribution scheme for the cylindrical Janus metasurfaces to improve the aperture efficiency. Both simulated and measured results verify the effectiveness of the proposed design. The proposed conformal Janus metasurface can provide theoretical references for applications of vortex electromagnetic communication especially in conformal platforms.