Fig. 2.

Simulation of a single film-coupled nanoparticle. Left: Relative electron surface density showing the exited surface plasmon polariton propagating over the metal film. Right (top): A plane wave is incident at 75° from normal on the nanoparticle. Right (bottom): A close-up of the near-fields surrounding the nanosphere; note the large field amplitude directly below the sphere. Looking closer yet, it can be seen that the fields penetrate into the nanosphere a distance on the order of the Thomas-Fermi screening length.