Tunable plasmon induced transparency with high transmittance in a two-layer graphene structure

Abstract

A dynamically tunable plasmon induced transparency planar structure with double layers hollow-cross graphene array is proposed in this paper. Due to energy oscillating back and forth between two weak hybridized states made up of upper and lower graphene, a transparent window during two resonance points is generated, and the PIT curve fits well with the Lorentz model. Via tuning the Fermi energy of graphene, a transparent window with the maximum transmissivity of 98.3% and modulation depth of 17.3% can be dynamically manipulated. In addition, the amplitude and frequency of the transmittance can be controlled by electrical doping without changing the structure. The structure provides a new scenario for innovative designs of plasmon-induced transparent structures. The proposed graphene-based PIT metamaterial shows promising applications of slow light technology, switchers, and filters in THz frequencies.