Multiple OAM vortex beams generation using 1-bit metasurface

In this paper, a novel method to generate multiple orbital angular momentum (OAM) vortex beams is proposed using a 1-bit metasurface. Through carefully adjusting the phase shift of each element, mirror-symmetrical OAM vortex beams are generated in targeted directions by a 1-bit metasurface under plane-wave illumination. Moreover, the topological charges of the generated vortex beams arc opposite. Based on this phenomenon, dual-beam, four-beam, and full-space OAM vortex waves are respectively studied and generated by conducting full-wave simulations. Finally, a prototype of the proposed metasurface is fabricated and measured in an anechoic chamber. The measurement results show that multiple OAM vortex beams are successfully generated and detected, verifying the effectiveness of the proposed method. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement