Wide-angle wideband polarization-insensitive perfect absorber based on uniaxial anisotropic metasurfaces
Journal
Optical Materials Express
Journal Volume
10
Journal Issue
5
Pages
1193-1203
Date Issued
2020
Author(s)
Abstract
A wide-angle, wideband, and polarization-insensitive metamaterial (MM) absorber was studied based on the theoretical concept of uniaxial perfect matching layer (UPML) in the terahertz range. The MM absorber was designed as a multi-layered anisotropic array structure consisting of a conductive VIA, a bi-layered slot-FSS, and a split-ring resonator (SRR) separated by porous silica spacers. Each component is optimized to approach the required macroscopic uniaxial property for satisfying the reflection-less boundary condition. The SRRs and VIAs were found to play an important role in maintaining large absorption when the angle of oblique incidence increases under transverse electric (TE) and transverse magnetic (TM) polarization, respectively. The absorption achieves 90% in the frequency regime of 0.9 to 10.5 THz, corresponding to a bandwidth of 168% to the central frequency, and retains such high performance up to 60° oblique incidence for both TE and TM waves. © 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement.
SDGs
Other Subjects
Anisotropy; Polarization; Silica; Terahertz waves; Central frequency; Frequency regimes; Oblique incidence; Perfect matchings; Polarization-insensitive; Split-ring resonators (SRR); Transverse electrics; Transverse magnetic polarization; Ring gages
Type
journal article