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arXiv · 1811.01232

Designing Dual-Band Absorbers by Graphene/Metallic Metasurfaces

Saeedeh Barzegar-Parizi·Amin Khavasi
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Abstract

This article presents a novel approach for designing dual-band absorbers based on graphene and metallic metasurfaces for terahertz and mid-infrared regimes, respectively. The absorbers are composed of a two-dimensional (2D) array of square patches deposited on a dielectric film terminated by a metal plate. Using an analytical circuit model, we obtain closed-form relations for different parameters of the structure to achieve the dual-band absorber. Two absorption bands with obtained absorptivity of 98% at 0.55 and 1.54 THz for the graphene-based structure and 7 and 25 THz for the metallic-based case are achieved. We demonstrate that the graphene-based absorber remains as dual-band for a wide range of the Fermi level. Furthermore, the proposed dual-band absorbers have a polarization-insensitive characteristic remaining over a wide range of incident angles. The most important advantage of this device is its simplicity compared to previously reported structures.

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Saeedeh Barzegar-Parizi, Amin Khavasi. 2018-11-03. Designing Dual-Band Absorbers by Graphene/Metallic Metasurfaces. https://doi.org/10.1109/jqe.2019.2901992

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