Accurate sensing with dual-band absorber based on graphene doped lattice for terahertz frequencies

Dual-band absorbers using identical shaped graphene doped lattice, with high absorbance coefficients are investigated in this paper. A dynamically tunable dual-band terahertz metamaterial absorber is proposed based on a hybrid graphene-doped frequency selective surface (FSS) structure. The unit cell incorporates concentric square graphene ring resonators and a planar graphene sheet sandwiched between dielectric layers, supported by a metallic backing. These resonators are responsible for the resonance effect and enable dual-band operation. By adjusting the chemical potential of graphene through external gate voltage, the absorption peaks can be dynamically tuned, demonstrating strong spectral flexibility. Simulation results show a maximum absorption of ۹۹.۶۳% at ۳۲.۴۲ THz. Additionally, the impact of different dielectric substrates on the tunability and bandwidth separation is studied, revealing further structural reconfigurability. The proposed absorber also maintains high absorption efficiency under oblique incidence, indicating robust angular stability. These features make the structure a strong candidate for advanced THz sensing and stealth applications.

کلیدواژه ها:

Graphene doped ، Ring resonator ، Frequency selective surface ، Terahertz Metasurfaces ، Absorption coefficient ، Tunable absorber