Finite-Difference Time-Domain Modeling of Decay Rates in the Near Field of Metal Nanostructures

Abstract

We test the three-dimensional finite-difference time-domain method for the calculation of decay rates of an emitter placed in close vicinity to metal nanostructures. By choosing analytical solvable systems we asses its accuracy and indicate the issues deriving from near-field coupling, Ohmic losses and staircasing. The latter is found to be the most problematic one, because it gives rise to spurious peaks that survive even for very fine discretizations.