Optics and Photonics Society of Iran

In this paper we investigate the properties of graphene and its effect on a flat plasmonic waveguide. At first dielectric function of graphene by chemical potential (Fermi energy) changes was reviewed, then the dependence of the refractive index graphene to the chemical potential is also discussed. In practice chemical potential of graphene can be altered by applying various methods including applying voltage. Indeed by applying voltage an additional population of electrons is injected to graphene that lead to increase Fermi energy level and therefore a phenomenon named Pauli blocking will alter the imaginary part of electrical permittivity (or equivalently imaginary part of refractive index) of graphene. Because of relation between the absorption of light and imaginary part of refractive index of graphene, the absorption of light by graphene can manipulated dynamically by applying time-varying voltage. Finally a planar plasmonic waveguide with a graphene layer was designed and simulated, that graphene layer was exposed to surface plasmon polariton and waveguide behavior by changing the chemical potential was evaluated. By increasing the chemical potential in a specific interval, power transmission waveguide found a significant increase.