▎ 摘　　要

The asymmetric transmission has fascinated wide interest because of its novel applications. In this paper, we propose and present the design procedure and the simulation results of the tunable dual-band polarization-sensitive graphene chiral metasurface. The resonance wavelength depends on and is controlled by the graphene chemical potential. The two-dimensional chiral response of the structure, circular conversion dichroism (CCD), is tunable and is reached to 0.2. As an application of the tunable chiral structure, a novel tunable polarization-sensitive refractive index sensor with the maximum sensitivities of 7000-10000 nm/RIU is proposed and analyzed. For different kinds of the circularly polarized incident electromagnetic waves, the sensitivities are high and noticeable. This paper exposes a new way to propose other polarization-sensitive structures, such as switches and absorbers in the terahertz (THz) region. In addition, the proposed structure and its application could be useful in polarization-sensitive devices and systems.