Versatile orbital angular momentum vortex beam generator based on reconfigurable reflective metasurface

In this paper, a versatile orbital momentum (OAM) vortex beam generator based on reconfigurable reflective metasurface is proposed. The multiple OAM beams, high-order OAM beam, and mixed OAM modes beam can be effectively generated by the real-time reconfigurable reflective metasurface according to the external dynamic requirements. A prototype with 16 x 16 varactor-tuning metasurface and a programmable board with 256 independent channels are fabricated and measured to launch four vortex beams with different modes. Theoretical analyses and experiments show that the reconfigurable reflective metasurface is an efficient way to dynamically generate versatile OAM vortex beams for radio frequency applications. (C) 2018 The Japan Society of Applied Physics