Stochastic instability of chirped optical solitons in media with periodic amplification

We consider the propagation of chirped optical pulses in media with periodic amplification. The process is described by means of a variational approach. The nonlinear resonances and chaotic oscillations of the pulse width are studied. The stochastic instability with respect to the evolution of the width and the stochastic decay of pulses under periodic amplification are predicted. The decay length is calculated and compared with numerical simulations. The application for long-haul optical communications lines with amplifiers is discussed.