Polarization independent tunable bandwidth absorber based on single-layer graphene

Abstract

As the demand for cognitive understanding of the THz band continues to grow, there is significant potential for practical applications in designing optical devices operating in this frequency range. This paper proposes a polarization-independent tunable bandwidth absorber based on a monolayer graphene, capable of achieving an absorption rate higher than 0.9 in the 3–6 THz band. The absorber exhibits polarization incoherence due to the structural symmetry. Analysis of the electric field distribution indicates that the strong absorption effect of the absorber primarily arises from the coupling of localized surface plasmon resonance (LSPR). The absorber also demonstrates excellent tunability, both in terms of physical and chemical properties, while maintaining optimal absorption performance at a 45° incidence angle. This implies that the absorber holds significant potential for applications in fields such as biomedicine and communications.