Simulation of metallic nano-structures by using a hybrid FDTD-ADI subgridding method

We present a novel hybrid mesh refinement method for the simulation of dispersive metallic structures. Combining the FDTD method and an unconditionally stable ADI-FDTD scheme preserves the Courant limit while providing higher spatial resolution in refined areas. The subgridding method is developed for the simulation of dispersive metals using an auxiliary differential equation approach. The algorithm performs roughly two times faster than a conventional mesh refinement method.