Terahertz Perfect Absorber Based on Asymmetric Open-Loop Cross-Dipole Structure

Abstract

Equipped with multiple and unique features, a terahertz absorber exhibits great potential for use in the development of communication, military, and other fields where achieving perfect broadband absorption has always been a challenge. We present a metamaterial terahertz (THz) absorber comprising a cross-dipole patch, four symmetric square patches and an asymmetric open-loop patch with a good perfect absorption rate for TE and TM polarizations. The average absorption of more than 96% occurs in the frequency range from 2.4 THz to 3.8 THz, in which the absorptance peak can reach 99.9%, as indicated by simulated results. Our design has broad potential applications in THz couplers, as well as in fields like biology and security.