Modeling tunable graphene-based filters using leapfrog ADI-FDTD method

An improved one-step leapfrog alternating direction implicit finite difference time domain (leapfrog ADI-FDTD) method is proposed for simulating graphene-based filters operating at THz band, with the Drude model of monolayer graphene and associated auxiliary differential equation (ADE) technique implemented. Numerical results show that the S-parameters of the filter can be adjusted effectively by changing the chemical potential as well as layer number of graphene patch.