Polarization-Controlled Shared-Aperture Metasurface for Generating a Vortex Beam With Different Modes

Electromagnetic waves carrying orbital angular momentum (OAM) have drawn much attention in the fields of radar detection and wireless communication. In such applications, vortex beams with multiple OAM modes need to be transmitted and received at the same time. This communication introduces the shared-aperture concept into metasurfaces for generating OAM vortex beams with different modes. Two independent geometry phase profiles on the same aperture are utilized to modulate the phase of two orthogonal linear-polarization waves. The alliance of polarization and orbit provides a routine to generate two different OAM modes simultaneously and achieves higher aperture efficiency than the conventional shared-aperture schemes. In this manner, different OAM modes can be separated easily by hardware. The simulated results validate the proposed method and structure.