Manipulating plasmonic waves transporting on graphene with graphene nanoribbon

In this work, we simulate and analyze the influence of the short graphene nanoribbon on transporting of graphene plasmonic waves (GPWs) on an infinite graphene monolayer by a finite element method (FEM). We find that plasmonic waves transporting along one atomic-thick graphene are sensitive to short nanoribbons which are arranged near the infinite graphene sheet. There are two main different mechanisms for modulating GPWs transport on graphene sheet: One is that Fabry-Perot resonance of plasmonic waves on graphene nanoribbons, which function as the resonant line cavity; another is the formation of standing waves on the infinite graphene sheet based on GPWs reflecting at the end of graphene nanoribbon. Owing to tunability of the chemical potential μc of the doped graphene nanoribbon, we are also able to actively control plasmonic waves by gate voltage or chemical doping. The optical properties are also sensitive to the structural details of the system, namely width and distance modulation. It provides an additional handle to control plasmonic waves transferring and could find its application in designing infrared and THz plasmonic devices.