A Low-Profile Broadband Terahertz Absorber Based on Graphene

A low-profile (measuring 6 μm × 6 μm) broadband absorber intended for sensing applications at terahertz frequencies is presented in this paper. The proposed design features a dielectric material, a metallic ground plane composed of copper, and a slot-loaded rectangular resonator made with graphene. The proposed absorber showcases exceptional absorption properties, achieving over 90% absorption throughout a broad frequency range of 0–18 THz. At 12.2 THz, the absorption performance is exceptionally high, achieving a remarkable absorption rate of 99.9%. In addition, the proposed absorber features a symmetric design that facilitates it to be polarization insensitive in nature. Moreover, Transverse-Electric (TE) and Transverse-Magnetic (TM) waves are both able to exhibit stable properties when the incidence angle (θ) ≥ 40°.