Evolution of femtosecond pulses in single-mode fibers having higher-order nonlinearity and dispersion

Using computer simulations, we examine the effects of higher-order dispersive and nonlinear propagation processes on the spectral and time development of ultrashort, high-intensity pulses propagating in single-mode optical fibers having normal dispersion. Our results indicate that both the cubic-dispersion term and the shock term of the nonlinear Schrödinger equation contribute to asymmetry in the pulse power spectrum and cause highly nonlinear chirp.