Control of the Surface Plasmon Resonance of Two Configurations of Nanoparticles: Simple Gold Nanorod and Gold/Silica Core/Shell

We report on the study of optical properties of ellipsoidal nanoparticles forms using Gans’s theory and Drude model; we introduce important parameters such as surrounding medium, shell thickness. Nanorods shaped nanoparticles are distinguished of others forms by the appearance of two peaks corresponding to their plasmonic bands: transverse mode placed in the visible region and the longitudinal mode located toward longer wavelength. The simulation results show a strong dependence of core/shell ratio and surrounding medium on longitudinal resonance. Nano shell nanoparticles composed with a big core (gold) aspect ratio are more shifted with increasing of silica layer