Multicontrolled Multiresonance Generation in THz Metamaterial Absorber

A multitunable, ultrathin terahertz (THz) metamaterial absorber is implemented with the hybrid resonator of graphene and phase change material, vanadium dioxide (VO2). The dimensions and geometry of resonator are selected to operate with multiple resonances, which can be controlled electrically, thermally, and by angle of incidence on electromagnetic (EM) wave. The resonances can also be separated and merged to obtain the broad or narrow spectrum for appropriate values of Fermi energy of graphene and thermal conductivity of VO2. The absorber can offer a high thermal sensitivity. The hybrid resonator utilizes the interface of conductive-dispersive boundaries, and hence, the quality factor of the generated resonances can be controlled using the incidence angle. Few generated resonances can be independently tuned using all the tuning factors. Moreover, Brewster’s effect generates few resonance peaks with the specific polarization of the incident wave. The operation of absorber is validated using multiple interference and reflection theory.