Tunable broadband angular selectivity for s-polarized terahertz incidences

While achieving broadband angular selectivity for p-polarized wave has been well studied, it is still challenging for s-polarized wave. The reason is that at high frequencies such as terahertz spectrum, the permeability of materials has always approached unity. Here, we propose a solution to implement broadband angular selectivity for s-polarized incidences by combining an effective anisotropic diamagnetic medium and a staggered photonic structure. The diamagnetic medium is constructed with periodically arranged metallic rings, exhibiting negligible frequency dispersion in an ultra-wide terahertz band. By incorporating temperature-dependent dielectric into staggered structure, a thermally tunable broadband angular selectivity system is presented, with an adjustable selective angle ranging from 0° to 40°. Full-wave simulations verify the effectiveness of the proposed approach, breaking through the polarization limitation of the existing angular selectivity technology. The proposed approach is simple, robust, and scalable from microwave to terahertz frequencies.