Wideband finite-difference time-domain modeling of graphene via recursive fast fourier transform

An efficient method based on the recursive fast Fourier transform (FFT) to incorporate both the intraband and interband conductivity terms of Graphene into the finite-difference time-domain (FDTD) method is proposed. As it only requires numerical values of the conductivity, it not only does not force any restriction of the conductivity models, but also can directly take into account material properties obtained from measurement. It reduces the total computational cost from O(N
²
) to O(Nlog
²
N).