Plasmon Induced Transparency in Graphene-based Side Coupled two Rectangular Nano-cavities-like structures

We investigate numerically the plasmon analogue of electromagnetic induced transparency (EIT) in a compact graphene-based waveguide coupled to two rectangular nano-cavities-like structures made out of graphene nanoribbons. The cavities are placed symmetrically on each side of the bus waveguide, giving rise to a V-like state in analogy with three level atomic systems. In this configuration, the cavities are directly coupled to the waveguide, and consequently both play the role of the bright mode. By slightly detuning the Fermi energy level of the cavities, we show the possibility of generating a narrow transparency window, that's, the plasmon induced transparency (PIT). The resonance peak occurs as a consequence of destructive interference between the cavities acting like coupled radiative oscillators. We also demonstrate that by appropriately shifting (symmetrically) the Fermi energy levels of the cavities, one could dynamically tune the resonance peak frequency. The proposed structure may help the design of highly integrated optical devices. (C) 2019 Elsevier Ltd. All rights reserved.