Simplified Terahertz Wideband Metamaterial Absorber

Metamaterial absorbers have received a lot of interest due to the fact that at the resonant frequencies they can be impedance matched to free space, thereby providing remarkably high absorption. In this paper, a coplanar broadband metamaterial absorber (MA) is proposed at terahertz frequencies. An appropriate placement of split ring resonators (SRR) with different radii and thicknesses is used to achieve a strong absorption (>99% at 4.016 THz). The structure is further optimized in order to improve the bandwidth (BW) of the absorber (650 GHz, >32% improvement) and to achieve a flatter curve (with a 14.7% improvement). The optimization of the structure results in enhanced absorption of 99.99% at 4.16 THz. Furthermore, owing to its coplanar design it is reasonably easy to manufacture.