Application of Graphene-Based Metasurface Plasma-Induced Transparency in Terahertz Band Optical Switches

In this paper, a monolayer graphene-based metasurface that can achieve plasma-induced transparency (PIT) is proposed. This metasurface consists of a horizontal strip and a pair of vertical ribbons. The simulation results of Finite-Difference Time-Domain (FDTD) method perfectly match with the theoretical results based on Coupled-mode Theory (CMT). Based on the dynamic modulation characteristics of graphene, an optical switch is studied with a vibration amplitude of 94.7%, 89.59% and 89.58%, corresponding to frequencies of 3.34 THz, 3.86 THz and 4.36 THz, respectively. The proposed graphene-based metasurface has potential applications in mid-infrared photoconducting devices, this work has a certain theoretical significance for the development of terahertz dynamic integrated photonic devices.