Transient quasi-phase matching SRS generation

We present a new, to our knowledge, method of anti-Stokes generation at stimulated Raman scattering in media with variations of third order nonlinearity (X (3)) along longitudinal coordinate. By numerical simulation the quasi-phase matching condition in different media and achievement of high efficiency of transient anti-Stokes conversion are obtained. The dependence of energy conversion from pump into anti-Stokes wave on the relation of input intensity of pump and Stokes waves is computed. We received the models of media in which the efficiency of anti-Stokes generation exceeded 30%. The results of the study can be used for the development of new effective nonlinear-optical devices for laser frequency conversion.