Terahertz polarization reflective devices based on one-dimensional grating structure

In this paper, the application of rectangular metal reflective grating as a polarization device is studied using a rigorous coupled-wave analysis method. Three polarization reflection devices are presented in the terahertz band. In addition, data verification is achieved based on the finite element method and the light field distribution of the device is analyzed to explain the physical mechanism. One of these devices splits the planar light into two mutually orthogonal output beams. The efficiency of TE polarization is 98.07%, and the efficiency of TM polarization is 97.86%. Furthermore, the process parameters of the three polarization devices, as well as the influence of incident wavelength and incident angle on efficiencies are also studied in the terahertz band.