Terahertz dual-tunable absorber based on hybrid gold-graphene-strontium titanate-vanadium dioxide configuration

Abstract

A terahertz dual-tunable polarization-independent metamaterial absorber based on hybrid gold-graphene-strontium titanate (STO)-vanadium dioxide (VO2) configuration is proposed. The results show that the absorption rate of absorber can achieve 98.3% at 0.2 THz. Moreover, both the absorption frequency and absorption rate of the absorber can be dual-tuned by varying the chemical potential of graphene and temperature of STO and VO2. Additionally, the performance of the absorber is theoretically analyzed by using the coupled mode theory (CMT) and impedance matching theory (IMT). Finally, the changes in the absorber's absorption spectra are discussed when the depth of STO and VO2 layers is modified. This work provides a theoretical basis for the designs of dual-tunable absorbers and filters, and also offers a new method for switching and modulation of THz radiation.