THEORY OF GIANT RAMAN-SCATTERING FROM SEMICONTINUOUS METAL-FILMS

The local electric fields in a semicontinuous metal film are shown to exhibit giant fluctoations in the visible and infrared spectral ranges , when the dissipation in metallic grains is small. The field fluctuat ions result in significantly enhanced Raman scattering from semicontin uous metal films. The scaling analysis is performed to describe giant Raman scattering in thr vicinity of the percolation threshold. A theor y of Raman scattering from these films is developed. A numerical metho d based on the theory is suggested and used to calculate Raman scatter ing from silver semicontinuous films. Results of the simulations an co mpared with recent experimental observations.