Tunable plasmon-induced transparency based on bright-bright mode coupling between two parallel graphene nanostrips

Tunable plasmon-induced transparency (PIT) is realized for the mid-infrared region only by using two parallel graphene nanostrips. The weak hybridization between the two bright modes results in the novel PIT optical response. The performance of the PIT system can be controlled by changing the geometry parameters of graphene nanostrips. At the same time, the resonance frequency of transparency window can be dynamically tuned by varying the Fermi energy of the graphene nanostrips via electrostatic gating instead of re-fabricating the nanostructures. Moreover, a figure of merit (FOM) value as high as 12 is achieved in the proposed nanostructures based on the performed sensitivity measures. Such proposed graphene-based PIT system may open up avenues for the development of compact elements such as tunable sensors, switchers, and slow-light devices.