FDTD Modeling of Graphene Devices Using Complex Conjugate Dispersion Material Model

Graphene-based devices constitute a pioneering field of research for their extraordinary electromagnetic properties. The incorporation of appropriate models into numerical simulators is necessary in order to take advantage of these properties. In this work, we propose a method to incorporate graphene-sheet models into the FDTD method. The use of vector-fitting techniques expands the permittivity of graphene into a rational function series of complex conjugate pole-residue pairs, which is implemented into FDTD by an auxiliary differential equation formulation. Simple waveguiding problems validate our approach.