Influence of weak temporal nonlinear dispersion and weak second order dispersion on picosecond pulse propagation in optical fiber with cubic nonlinearity

摘要

Using computer simulation, we investigate an optical wave formation in optical fiber with cubic nonlinearity under the influence of time dispersion of nonlinear response. We show possibility of attosecond pulses train formation at the shock wave front. This train takes place if time dispersion ofnonlinear response influences significantly on laser pulse propagation in optical fiber. The influence of frequency modulation is considered as well. Our analysis is based on original transform of well-known generalized nonlinear Schrodinger equation with temporal derivation from nonlinear response. We analyze the influence of weak temporal dispersion and weak second order dispersion on propagation of picosecond (or femtosecond) pulse with low intensity in nonlinear optical fiber. Under such conditions the formation of train sub-pulses, which duration is from ten to fifty times shorter than input pulse duration, are obtained. We investigate dependence of distance of train pulse formation on dispersion coefficient, coefficients characterizing nonlinearity and dispersion of nonlinear response. For computer simulation we use conservative difference schemes, which allow us to make simulation with big accuracy.