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

TL;DR

This paper introduces a new class of ultrathin high-Q passband filters using all-dielectric metasurfaces that leverage multipolar resonances, with potential applications in antennas and frequency selection.

Contribution

It develops a rigorous analytical model for designing high-Q filters based on multipolar resonances in dielectric metasurfaces, validated by numerical simulations.

Findings

Achieved high-Q resonances in ultrathin dielectric filters.

Demonstrated broadband dielectric mirrors with narrow transmission bands.

Showcased improved out-of-band selectivity in antenna designs.

Abstract

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.