Backward and forward quasi-phase-matched SRS in nonlinear periodical structures

From wave Maxwell equation we derive a system of differential equations described multiwave backward and forward stimulated Raman scattering with diffraction effects. The results of numerical simulations of this system are quantity and quality agreed with experimental results. The numerical simulations of quasi-phase matched forward and backward SRS showed that the influence of backward SRS on QPM structure realization results in the small difference between layers length of optimal QPM stmcture and small decreasing of resulting anti-Stokes conversion efficiency (~25%at backward and forward SRS, ~3O% at forward SRS). The oscillations of optimal layers length are partially connected with backward SRS influence and with insufficient precision of layers length determination due to high computational complexity of this task.