Influence of optical losses on the dynamics of nonlinear propagation of pulses in single-mode fiber waveguides

The results are reported of numerical experiments on nonlinear dynamics of ultrashort pulses in fiber waveguides. The quantitative criteria for a structural instability of solitons in such waveguides are derived. A study is made of the influence of the optical losses on the dynamics of formation and decay of bound soliton states in fiber waveguides. It is shown that the main contribution to the rms duration of a multisoliton pulse does not come from a narrow central peak but from the pedestal of the pulse, which gives rise to additional difficulties in the development of high-transmission-rate fiber-optic communication lines utilizing solitons.