Electrically tunable polarizer based on anisotropic absorption of graphene ribbons

We theoretically demonstrate that an electrically tunable polarizer can be obtained using a periodic array of graphene ribbons supported on a dielectric film on top of a thick piece of metal. The polarizing mechanism originates from anisotropic absorption of the graphene ribbons. The results of fullwave numerical simulations reveal that absorption of 0.0075 for one polarization and 0.9986 for another polarization can be obtained at normal incidence in the THz range. For circular incidence polarization, the corresponding polarizing extinction ratio increases to 65 dB.