Terahertz wideband wave plates designed by stacking multilayered metasurface with different geometries

Abstract The use of metamaterials in terahertz (THz) polarization wave plates is widespread. Metallic metamaterials, however, typically operate within a constrained bandwidth and have a large ohmic loss. All‐dielectric metamaterials could address these issues. To achieve an ultrawide‐band at THz frequencies, a multilayered silicon metasurface with elliptical or rectangular pillars has been employed. According to simulations, the achromatic relative bandwidth of the dielectric metamaterial can remain flat within a broadband with the appropriate structural parameters. Additionally, a scoring system with error analysis is added to help with choosing the geometry of terahertz polarization wave plates with various layers of metasurface. Due to its flexible polarization control capability, the proposed multilayer metasurface may open the door for arbitrary phase delays of incident waves.