Nanoplasmonics FDTD Simulations Using a Generalized Dispersive Material Model

This work deals with the use of our recent generalized dispersive material (GDM) model built on Pade approximants that is applied to FDTD simulations of nanoplasmonic structures. In particular, our original formulation is compared to the classical recursive-convolution technique for the Lorentz oscillator using a complex recursive accumulator. The proposed GDM model is then used to simulate the spectral response of an array of 2D gold nanoslits, and the results are successfully validated with frequencydomain solutions. Another simulation example shows the transmission, reflection, and absorption spectra obtained from 3D FDTD parallel calculations of a multi-layer semicontinuous metal film. The numerically simulated results are then compared to data obtained from the optical characterization of a semicontinuous film sample with the same topology, and a comparison of both results demonstrates a good fit. Each example uses a modulated incident pulse with a fixed carrier frequency and a Gaussian envelope.