Cross-polarization and co-polarization waves regulation metasurface

Most reported metasurfaces based on pancharatnam berry (PB) phase principle mainly focus on cross-polarization wave regulation, but little discussion on co-polarization wave regulation. In this article, we propose a hollow cross-shaped metal disc metasurface to achieve the modulation of cross-polarization and co-polarization terahertz waves. Under right circularly polarized wave incidence at frequency of 1.4THz, this structure achieves cross-polarization and co-polarization vortex beams with different topological charges, cross-polarization and co-polarization wave deflection beams with different deflection directions, and cross-polarization and co-polarization offset focusing beam. Moreover, the simulation results are consistent with the theoretical calculation predictions. The results indicate that the metasurface can decouple incident circularly polarized waves, regulate cross-polarization and co-polarization reflected waves, and provide a new freedom degree for the control of circularly polarized waves.