Theory of giant Raman scattering from semicontinuous metal films

Abstract

The local electric fields in a semicontinuous metal film are shown to exhibit giant fluctuations in the visible and infrared spectral ranges, when the dissipation in metallic grains is small. The field fluctuations result in significantly enhanced Raman scattering from semicontinuous metal films. The scaling analysis is performed to describe giant Raman scattering in the vicinity of the percolation threshold. A theory of Raman scattering from these films is developed. A numerical method based on the theory is suggested and used to calculate Raman scattering from silver semicontinuous films. Results of the simulations are compared with recent experimental observations.