A Graphene-Based Broadband Metamaterial Absorber

Abstract

This paper presents a broadband terahertz (THz) metamaterial absorber. The unit cell structure of this absorber consists of three layers. The top layer of the structure contains a circular graphene ring. At the center frequency of 2THz, this circular graphene ring has a fractional bandwidth of 67% and absorptivity of more than 90%. The proposed absorber is polarization insensitive because of its fourfold symmetrical structure. The graphene parameter is optimized to get maximum bandwidth. This metamaterial offers TE and TM polarization insensitive up to a 60° incident angle of electro-magnetic wave.