Incorporating interband conductivity into ADI-FDTD method to simulate graphene

Abstract

The interband conductivity of graphene approximated by using Pade fit method is incorporated into the alternating-direction implicit finite difference time domain (ADI-FDTD) method to simulate graphene. The accuracy of the Pade fit method is verified. The ADI-FDTD method is unconditionally stable, so its computational efficiency is greatly larger than that of FDTD method, which is validated by numerical example. Besides, it shows that the interband conductivity of graphene has important effect on numerical result at high frequency range, especially when chemical potential is small.