Switchable and tunable terahertz metamaterial absorber based on graphene and VO2 resonator with ultra-broadband and multi-band absorption

Abstract

Vanadium dioxide (VO2) and graphene have been combined to create new design possibilities for high-performance metamaterial devices, which offer an alluring foundation for electromagnetic absorption applications. The structure under investigation, which is based on patterned graphene-vanadium dioxide and metamaterial absorbers, is capable of achieving both broadband and multi-band absorption. Also, the offered structure is tunable and switchable in the proposed wide-band range. We theoretically suggest a switchable and tunable graphene and VO2 resonator-based Broadband and Multi-band terahertz (THz) metamaterial absorber. The proposed absorber can achieve more than 99% absorption while operating in multi-band absorption mode at 2.26, 6.68, and 7.71 THz. Moreover, it can achieve absorption of more than 90% when operating in broadband mode, which has a bandwidth of 8.74 THz within the frequency range of 2.76–11.5 THz. In the 3.12–11.01 THz frequency band, this absorption percentage is 98%. The absorption spectra can be tailored by altering the chemical potential of the graphene layer and the conductivity of VO2. The suggested absorber also has a wide incidence angle insensitivity. As a result, the suggested absorber can be considered a good choice for various THz frequency range applications.