Terahertz cut-wire-pair metamaterial absorber

摘要

Metamaterial absorbers are usually made of resonant structures backed by a metallic reflector, relying solely on the ohmic and dielectric losses generated by magnetic resonance. In this work, we apply an alternate approach to obtain absorption by overlapping magnetic and electric resonances in a conventional cut-wire-pair metamaterial. A terahertz absorber is designed following that approach achieving up to 99% absorption in simulations without employing a reflector, while the fabricated prototype absorbs up to 82% (excluding the loss of the silicon wafer) of the incident waves at 56 THz. The results empirically confirm that perfect absorption can be obtained using resonance superposition. In addition, the high absorption strength and the possibility to permit the transmission of the proposed metamaterial absorber make it different from other conventional ones.