Sensing based on plasmon-induced transparency in H-shaped graphene-based metamaterials

Abstract Graphene can support surface plasmon polaritons (SPPs) in terahertz band and the graphene SPPs sensors are widely used in the field of terahertz micro- and nano-optical devices. In this paper, we propose an H-shaped graphene metasurface and use finite-difference time-domain (FDTD) method to investigate its generated plasmon-induced transparency (PIT) phenomenon. Our results show that the Fermi energy levels, as well as the certain shape parameters, can effectively modulate the PIT phenomenon of the proposed structure. Interestingly, changing some of these shape parameters can excite two dips into three. In terms of sensing performance, the maximum values of sensitivity and figure of merit (FOM) are 1.4028 THz/RIU and 17.97, respectively. These findings offer valuable guidance for the use of terahertz micro-nano optical graphene SPPs sensors.