Wavelength dependence of the retardation effects in silver nanoparticles followed by polarization resolved hyper Rayleigh scattering

We have experimentally investigated the polarization resolved hyper Rayleigh scattering response from an aqueous suspension of silver nanoparticles the diameter of which is 40 nm. In the spectral region, where the harmonic frequency is in resonance with the dipolar mode of the surface plasmon resonance of the particles, the results unambiguously demonstrate that the origin of the response stems from the breaking of the centrosymmetrical geometry of the particles. (c) 2005 Elsevier B.V. All rights reserved.