Design of High-Q Passband Filters Implemented Through Multipolar All-Dielectric Metasurfaces

We propose a novel class of ultrathin high-Q passband filters designed by properly combining different multipolar resonances sustained by an all-dielectric metasurface. A rigorous analytical model, based on surface impedance homogenization and accounting for the effects of both dipolar and the quadrupolar contributions to the overall scattering response, is derived and verified through numerical simulations. Then, it is described how it is possible to engineer the interactions between dipoles and quadrupoles in a metasurface made by core-shell spherical elements to design ultrathin and broadband dielectric mirrors with a narrow transmission band. The proposed filters exhibit high Q-factor resonances and can be implemented using realistic materials at either microwave or optical frequencies. Finally, we discuss how the proposed dielectric filters can be used to design self-filtering aperture antennas exhibiting higher out-of-band selectivity compared with those implemented through metallic resonators.

Automated summary

This study proposes a novel approach to design ultrathin high-Q passband filters by utilizing multipolar resonances sustained by all-dielectric metasurfaces. The rigorous analytical model and numerical simulations confirm the effectiveness of the design, which can achieve high Q-factor resonances and be used for self-filtering aperture antennas with higher out-of-band selectivity.