Dual-broadband Terahertz metamaterial absorber using a single asymmetric resonator

Abstract

In this work, we propose a novel dual-broadband terahertz (THz) metamaterial absorber (MA) using a single asymmetric resonator, which is designed by diagonally splitting a single square gold patch with two opposite corner defects. The proposed absorber has the extended absorption bands with absorptivity above 90% in two frequency ranges of 2.36–3.82 THz and 5.37–6.33 THz. The physical origin of dual-broadband absorption is investigated by the impedance matching theory and the electric field distributions. We also investigate the influences of oblique incidence and polarization angles on dual-broadband absorption performance. Compared with other broadband THz MAs based on asymmetric resonators, our dual-broadband THz MA has excellent performances such as simple structure, high absorptivity, broadband and dual-band absorption characteristics.