Quad-band tunable graphene-based metamaterial absorber operating at THz frequencies

A graphene-based metamaterial absorber is presented to act at four resonance frequencies of the far-infrared range. The proposed absorber consists of a graphene-based resonant metasurface at the top, dielectric layer and gold layer as the ground plane at the bottom of the structure. The Results demonstrate that absorption peaks larger than 0.9 can be attained at four resonance frequencies under a transverse magnetic polarized incident wave. Also, resonance frequencies of the structure can be tuned through changing graphene Fermi energy. The conclusions may be beneficial for realizing multi-band next-generation optoelectronic devices based on graphene.