Anisotropic terahertz graphene metamaterial multi-band absorber based on an orthogonal dual-ribbon configuration

Abstract This study presents a dynamically reconfigurable anisotropic graphene-based metamaterial absorber operating across the 0.5–4.7 THz range. The unit-cell design, composed of two orthogonal pairs of graphene ribbons, produces direction- and polarization-dependent electromagnetic responses. Numerical simulations using CST Studio Suite, complemented by an equivalent circuit model (ECM) analyzed in MATLAB, reveal the transverse electric (TE) and transverse magnetic (TM) resonances. At a Fermi energy of 0.6 eV, the absorber demonstrates high tunability and pronounced linear dichroism (LD) up to 99.1%. The structure supports four TE and two TM high-absorption resonances, achieving absorption rates above 94.5% and 82%, with peak values of 99.68% (TE) and 99.92% (TM). These distinct TE/TM spectral fingerprints offer strong potential for polarization-sensitive THz devices, photonic platforms, and Frequency-Encoded Secure Identification (FESID) applications.