Tunable all-graphene-dielectric single-band terahertz wave absorber

Abstract

We propose an all-graphene-dielectric tunable terahertz absorber composed of a graphene microstructure layer, a dielectric spacer layer and a metallic ground plane. The absorption performance and internal mechanism of the absorber have been comprehensively analyzed. When E f changes from 0 eV to 0.6 eV, the absorption peak changes from 0.48 THz to 1.579 THz. In addition, we present a novel equivalent circuit model to analyze the mechanism of the absorber. The numerical calculation results are basically consistent with the result of the equivalent circuit model. Our work provides a reference for the design and theoretical study of all-graphene terahertz devices.

Design of an Ultra-thin Hepta-band Metamaterial Absorber for Sensing Applications

“…However, these approaches suffer from technical difficulties due to larger size and thickness which limits practical applications. In addition, proposed absorber utilizing single metallic structure demonstrates seven absorption peaks with polarization insensitive characteristics which is better than previously reported MMA [10,12,14,30,32].…”

“…The real (Z) and imaginary (Z) should be nearly one and zero, respectively, as impedance of the MMA must be equal to free space impedance to achieve perfect absorption [10,28]. [40].…”

“…Metamaterial absorber (MMA) has drawn significant attention in THz range due to its perfect absorption properties which are difficult to find in natural materials. The first MMA was demonstrated by Landy et al which attracts considerable attention [9] and since then, different kinds of MMAs have been proposed including single [10], dual- [11][12][13], triple- [14], quad- [15], penta-band [16], broadband [17], tunable [18] and polarization insensitive [11] absorbers. Among these, multi-band MMA with polarization insensitive characteristics have found great attention due to their use in applications such as materials detection [19], sensing of harmful gas [20] and spectroscopic imaging [21].…”

Recent progress in two-dimensional materials for terahertz protection

“…Therefore, the electromagnetic shielding effectiveness (EMI SE) could be written in dB as follow [16,34,35]: Because of the obvious SPPs in the THz band [30], graphene had been widely studied for THz protection [38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54]. However, the atomic monolayer graphene is almost transparent to THz wave, so the overall intrinsic absorption of monolayer graphene is highly limited [14,15].…”

Graphene-Assisted Narrow Bandwidth Dual-Band Tunable Terahertz Metamaterial Absorber

“…Landy et al reported a metamaterial absorber with perfect absorption characteristics for the first time [21]. Since then, various metamaterial absorbers operating in various frequency regions were achieved, from microwave to infrared range [22][23][24]. In terahertz region, Tao et al demonstrated the first narrowband absorber [25].…”