Second-harmonic generation taking into account dispersion of nonlinear susceptibility

Second-harmonic generation in the field of an ultrashort pulse and the prop agation of extremely short pulses in a medium with quadratic nonlinearity a re analyzed. Second-harmonic generation is analyzed taking into account the effect of second- and third-order group velocity dispersion and dispersion of nonlinear susceptibility up to the second order. Corrections, whose ord er of smallness is determined by the parameter (omega (L)t(p))(-1), where t p is the pulse duration and wt is the carrier frequency of the pump wave, a re obtained. For a large phase mismatch, two new solutions are found that d escribe the stationary evolution of solitary pump and second-harmonic waves in the regions of both anomalous and normal group velocity dispersions. (C ) 2000 MAIK "Nauka/Interperiodica".