| Utilizing the anomalous polarization effect of resonant domain gratings, in this paper, we developed a metallic grating with fused silica (SiO2) as the substrate and aluminum (Al) as the metal for the grating lines. The grating demonstrates unusual polarization properties for transmitted TE-polarized light and reflected TM-polarized light, with a period of 261 nm, near the incident wavelength of 266 nm. When the light source is vertically incident to the grating, the transmittance of TE polarized light can achieve 82%, and the extinction ratio can reach 220. In order to further improve the extinction ratio of the grating, in this paper, a layer of medium is added on the SiO2 substrate, and Al2O3 and Si3N4 are selected as the medium layer materials. Analysis of the simulation results indicates that when Al2O3 is employed as the dielectric layer material, the grating's extinction ratio reaches 240. When Si3N4 is used, the extinction ratio rises to 396. Additionally, the transmittance of TE-polarized light consistently exceeds 60%. The anomalously polarized grating has a wide range of potential applications in photolithography polarization systems, optical filtering, and other fields. |
