Tunable plasmonic optical responses and the sensing application in graphene-based metasurface

It is meaningful that the sensing performance is achieved in a simple graphene structure. In this paper, we proposed a simple graphene-based metasurface structure which contain a graphene ribbon and U-shaped graphene pattern, showing outstanding sensing performance in terahertz band. The transmission spectrum with three dips is excited in our proposed structure calculated by the finite-difference time domain (FDTD) simulation method. The results show that the transmission spectrum with three dips can be effectively tuned by the Fermi energy. Intriguingly, the tri-frequency detection of the sensing performance is focused on the proposed graphenebased metasurface. The maximum of sensitivity and figure of merit(FOM) for the sensing performance are 3.4269 THz/RIU and 21.92, respectively. These research results may pave the way for the development of optical terahertz sensing devices.