▎ 摘　　要

In this paper, a graphene metasurface based on split-ring resonators (SRRs) structure has been proposed and investigated numerically, which can achieve the highly efficiency switchability of anomalous refraction and planar focuing effects. Numerical simulation results indicated that the proposed graphene metasurface could not only realize polarization conversion with a transmission amplitude of about 0.4, but also achieve a full 2 pi phase shift by changing the geometrical parameters of SRRs structure. In addition, the efficiency of the cross polarization transmission is highly depedent on the Fermi energy level of graphene. By elaborating design of a spatially phase profile and arrangment of unit-cell structure, anomalous refraction and planar focusing effect can be achieved, and the efficiencies are also switched by only changing the Fermi energy level rather than the physical size. It could be believed that the effective switchable graphene metasurface would lead a new path for controling the wavefront of THz waves.