Theory for Nonlinear Mie-Scattering from Spherical Metal Clusters

Abstract

Using classical electrodynamics we determine the angular dependence of the light intensities radiated in second and third harmonic generation by spherical metal clusters. Forward and backward scattering is analyzed in detail. Also resonance effects in the integrated intensities are studied. Our work treats the case of intermediate cluster sizes. Thus it completes the scattering theory fo spherical clusters between Rayleigh-type analysis for small spheres and geometrical optics for spheres much larger than the wavelength for nonlinear optics. Since the particle size sensitivity of Mie-scattering is increased by nonlinearity, the results can be used to extract sizes of small particles from nonlinear optics. (submitted to Phys. Rev. B)