Metasurface with dual functions of circular polarized wave asymmetric transmission and unidirectional wave absorption

The metasurface is used for solving the problems that an existing asymmetric transmission metasurface is single in function and low in circularly polarized wave regulation and control efficiency, and comprises three layers of dielectric substrates which are sequentially arranged from top to bottom and do not make contact with one another. The upper surfaces of the three dielectric substrates are respectively printed with L-shaped and quasi-C-shaped metal resonance units which are periodically arranged, the longitudinal edges of the two metal patches are unequal in length, and the transverse edges of the two metal patches are opposite to each other; graphene patches are printed on the lower surfaces of the first dielectric substrate and the second dielectric substrate respectively, and a graphene floor is printed on the lower surface of the third dielectric substrate; in the process that the Fermi level of graphene is increased from 0 eV to 0.8 eV, the function of the metasurface is gradually converted from as