Broadband and high-efficiency reflective polarization rotator using metamaterials

A wideband and high-efficiency 90°polarization rotator based on ultrathin planar metamaterial is presented. It consists of the metallic hexagonal patches on the top layer of the dielectric substrate and a metallic film on the bottom layer. Initially, the explanation of the physical mechanism for the polarization rotator is presented according to the anisotropy media theory. Thereafter, we have discussed the influences of the structure dimension on the performance of the proposed polarization rotator. And finally, the structure is also fabricated. Results of the test show that it exhibits over 90％ polarization conversion ratio from 841GHz to 113GHz in the condition of normal incidence.