Optimal Modeling of Infinite Graphene Sheets via a Class of Generalized FDTD Schemes

The accurate and fully 3-D analysis of graphene surface conductivity models by means of a frequency-dependent finite-difference time-domain method is introduced in this paper. For the infinite sheet to be consistently simulated, the novel technique uses a set of periodic boundary conditions that lead to a unit cell excited with a spectral scheme in terms of a total-field/scattered-field formulation. On the other hand, graphene itself is modeled through a subcell approach and a complex surface conductivity concept defined by quantum mechanical equations. This conductivity model is next converted to a volume one in order to permit a realistic time-domain study. Numerical outcomes, addressing a variety of applications, reveal a promising coincidence with those acquired from analytical closed-form expressions.