Subcell modeling of a plasmonic Drude nanosphere

A subcell model is presented that mimics the low frequency response of a Drude nanosphere. The approach is based on the observation that the inclusion of a dielectric sphere into a finite-difference time-domain cell requires to appropriately tailor the cell´s material properties utilizing an effective medium approach. A circuit based methodology is employed that allows to easily incorporate the effective medium model in the finite-difference time-domain method. The theoretically derived results are supported by numerical experiments.