The HIE-FDTD Method for Simulating Graphene

The hybrid implicit-explicit finite-difference time domain (HIE-FDTD) method is presented to simulate the graphene layer. By using the auxiliary differential equation (ADE) and Pade fitting method, both the interband and intraband conductivity of the graphene are incorporated into the HIE-FDTD method. The time step increment in the proposed method is not determined by the fine meshes in the graphene layer, so the computational efficiency of this method is greatly improved from that of the conventional finite-difference time domain (FDTD) method, which is well validated by numerical examples. Besides, the numerical simulation also shows that the interband conductivity of the graphene has important effects on the performance of the graphene, especially at higher Terahertz (THz) spectra.