Observation of stimulated surface-enhanced Raman scattering through grating excitation of surface plasmons

Abstract

We report on an experiment with surface-enhanced Raman scattering on gratings overcoated by copper phtalocyanine that shows that, because of the resonant excitation of surface plasmons, a stimulated Raman scattering process occurs. The corresponding threshold value of the pump power is rather low, of the order of 40 mW. This observation was made with a thin (5-nm) film of copper phtalocyanine. The theoretical study is developed by coupled-mode analysis that makes full use of the electromagnetic resonant feature of this nonlinear interaction.