Electromagnetic induced transparency in graphene waveguide structure for Terahertz application

Abstract

Electromagnetic Induced transparency (EIT) has been considered as a possible manner to implement plasmonic devices for slow light and sensing applications. In this paper, we proposed a novel design of graphene waveguide structure, which provides a tunable EIT response. Numerical results reveal that the plasmon induced transparency spectral response occurs due to the interference between quasi-dark mode and quasi-bright mode which exist in the loaded graphene resonator of the device. The EIT peak frequency can be tuned by changing the Fermi level of the graphene. An elaborate analysis of the relationship between the transparency frequency and graphene’s Fermi level, in turn, proved the two-dimensional nature of the graphene plasmon. Compared with previous designs, the proposed design can work in the THz frequency and provides a much sharper EIT window which is quite useful for sensing applications.