Realization of broadband terahertz metamaterial absorber using an anti-symmetric resonator consisting of two mutually perpendicular metallic strips

Abstract

This paper presents a scheme to achieve a broadband metamaterial absorber in the terahertz region, which is consisted of an anti-symmetric T-shaped resonator (formed by two mutually perpendicular metallic strips) on top of a metallic back layer separated by an insulator dielectric layer. The anti-symmetric T-shaped resonator can have a strong electromagnetic interaction with the incident beam, resulting in four different absorption peaks having adjacent frequencies, and the superposition effect of these adjacent peaks produces a broadband absorption. The resonance bandwidth of greater than 80% absorption can have 0.58 THz ranging from 1.54 to 2.12 THz, and its relative resonance bandwidth is 31.69%. The resonance bandwidth and relative resonance bandwidth can be scaled by controlling the parameters of two mutually perpendicular metallic strips in the anti-symmetric T-shaped resonator. Moreover, the parameter optimization of the anti-symmetric T-shaped resonator can realize five discrete absorption peaks with adjacent frequencies, and their combined effect can obtain not only broadband absorption but also a greater absorption bandwidth compared with the case of broadband absorption having four absorption peaks.

Machine learning assisted hepta band THz metamaterial absorber for biomedical applications

“…As a result, the absorption response shows red shift phenomenon as the h s and a increases 15 . Table 4 compares previously reported studies 10,11,13,15,28,[46][47][48] with proposed MMA in terms of unit cell size, thickness, and resonating frequencies, indicating that the proposed MMA has seven absorption peaks with compact metallic structure, which is superior to previously reported MMA.…”

An ultrathin triple‐band absorber for tuneable THz bio‐sensing

“…Initially, the electrical properties of graphene are chosen from the literature. 19 These properties include chemical potential, μ = 0eV c with relaxation time, τ = 0.1ps r , and temperature T = 300K. To provide the biasing, ion-gel is introduced above this graphene ring with height h = 0.1μm ion .…”

“…Therefore, a single layer of graphene with thickness is grown above SiO 2 whose inner and outer radius are $${r}_{i}$$ = 5 µm and $${r}_{o}$$ = 7 µm, respectively. Initially, the electrical properties of graphene are chosen from the literature 19 . These properties include chemical potential, $${\mu }_{c}=0 \mathrm{eV}$$ with relaxation time, $${\tau }_{r}=0.1 \mathrm{ps}$$, and temperature $$T=300 {\rm{K}}$$.…”

“…Usually, to have more absorption peaks (or the broadening of resonance bandwidths), the absorbers frequently utilize the design methods of multiple‐layer stacked structure and coplanar super‐unit structure. To realize broad bandwidth, two perpendicular antisymmetric resonators are used 19 . As multiple frequency‐band increase, structure deformation as a toothed resonator, 20 split ring resonator, 21 perforated square‐patch, 22 and so on the tenability of the absorber can be changed by changing material conductivity 23 .…”

“…To realize broad bandwidth, two perpendicular antisymmetric resonators are used. 19 As multiple frequencyband increase, structure deformation as a toothed resonator, 20 split ring resonator, 21 perforated square-patch, 22 and so on the tenability of the absorber can be changed by changing material conductivity. 23 This absorber also lacks tenability, unlike the graphene absorber.…”