NONPARAXIAL PROPAGATION OF PARAMETRIC SPATIAL SOLITONS

摘要

Parametric interaction among pump, signal and idler Gaussian beams in the PPLN material using 2D BPM based on finite-difference implicit Crank-Nicholson scheme is numerically investigated. Pade (1,1) approximants have been successfully introduced for the three coupled nonlinear nonparaxial propagation equations. The NL-PML boundary conditions to tilted propagation of spatial solitons in periodically poled second order nonlinear materials were successfully applied. It is demonstrated that the NL -PML is extremely effective in absorbing out-going spatial solitons that impinge the boundary for a wide angular spectrum of wave propagation. Using of sufficiently smooth conductivity profiles and termination of NL-PML media by controlled TBC offer further significant improvement in the accuracy of the numerical solutions of nonparaxial propagation of spatial solitons at the grazing angles.