Tunable terahertz broadband absorber based on a composite structure of graphene multilayer and silicon strip array

We propose a terahertz broadband absorber composed by silicon strips with continuous graphene on top of a metal mirror. The simulation results show that under the combined effect of the Fabry-Perot resonance and the dipole mode oscillation excited in the silicon strip array interacting with graphene, this structure can achieve an ultra-wide absorption band from 0.73 to 1.95 THz with absorbance of 90%. By changing the size of the silicon strips or the Fermi level of graphene, the working band of the absorber can be tuned.