Ultra-wideband polarization rotation reflective metasurface based on monolayer rhombus hollow structure

A novel broadband polarization rotation (PR) reflective Metasurface (PRRM) with a high polarization conversion ratio (PCR) is proposed in this paper. The PRRM consists of a periodic array of rhombus hollow structures (RHSs), which can rotate an incident linearly polarized wave by 90°. As the RHS stimulates four resonances, a very wide operating frequency band is obtained. The surface current distributions on the structure are discussed to reveal the physical mechanism. In the frequency band of 14.2-36 GHz (a relative bandwidth of 86.9%), an incident linearly polarized wave is converted into its cross polarization with the PCR greater than 90%. To evaluate the energy loss, the Energy reflectivity ratio (ERR) is also calculated, and the ERR is greater than 90% within the band. The PCR of the RHS is also studied by simulating oblique incidence and different loss tangent of the dielectric substrate. The prototypes of the PRRMs are fabricated and measured. The measured results are in good agreement with the simulated ones, which indicates the validity of the designed structures.