Numerical studies on randomly distributed gold nano-net structures

A randomly distributed gold nano-net is studied numerically via FDTD simulations. The dispersion of gold is implemented through a generalized dispersive material (GDM) model built on Padé approximants. The simulation of the dispersive random nano-net structure demands both fine nanoscale geometry and large span area in order to cover the complexity of interactions at the scattering surface. Along with additional equations for dispersive response this poses a severe challenge in terms of an efficient numerical implementation, especially in 3D. To reduce the simulation time we studied and determined the minimal size of the individual 2D-frames, which can be calculated independently and in parallel on a multiprocessing system. The impact of the individual frame size on accuracy is analyzed for a representative nano-net sample.