Dynamically switching the asymmetric transmission and monodirectional absorption of circularly polarized waves using cascade composite resonator-graphene meta-surfaces

We propose a reconfigurable hybrid graphene meta-surface for modulating circularly polarized (CP) waves with dual functionalities of asymmetric transmission (AT) and monodirectional absorption. Such a meta-surface consists of three cascade dielectrics covered with identical metallic resonators and different patterned graphene sheets over the front and the back sides, respectively. The left-handed CP incidences will be transformed into right-handed CP counterparts efficiently with an AT-parameter of 0.8, and the state of transmission will be contrary when the incident CP waves are from the opposite direction. On the other hand, the proposed cascade composite resonator-graphene meta-surface can also function as a super monodirectional absorber to trap the forward incident CP waves at the same frequency range when we simply tune the Fermi energy of graphene. The proposed design should pave the way for building up more advanced meta-devices with multiple functionalities to manipulate CP waves.