Omni-directional, broadband and polarization-insensitive thin absorber in the terahertz regime

TL;DR

This paper proposes a thin, broadband, polarization-insensitive terahertz absorber that uses magnetic polaritons in layered structures to achieve nearly omni-directional perfect absorption in a compact form.

Contribution

It introduces a novel multilayer design that enhances absorption bandwidth via hybridized magnetic polaritons, significantly reducing absorber thickness.

Findings

Achieves near-perfect absorption in a thin layer

Enhances bandwidth by stacking layers with different geometries

Operates effectively for both TE and TM polarizations

Abstract

A nearly omni-directional THz absorber for both transverse electric (TE) and transverse magnetic (TM) polarizations is proposed. Through the excitation of magnetic polariton in a metal-dielectric layer, the incident light is perfectly absorbed in a thin thickness which is about 25 times smaller than the resonance wavelength. By simply stacking several such structural layers with different geometrical dimensions, the bandwidth of this strong absorption can be effectively enhanced due to the hybridization of magnetic polaritons in different layers.