Influence of noise on the propagation of light pulses in optical fibers

The method of path integration is used to solve the problem of the influence of weak noise on nonlinear propagation of an ultrashort light pulse in an optical fiber. A calculation is made of the correlation function and pulse intensity. It is shown that the coherent properties of a pulse deteriorate in a nonlinear medium. Noise also increases the pulse duration by an amount depending on the interaction length. It follows that steady-state propagation of pulses cannot be expected in the presence of noise.