Soliton Stability in Multimode Fibers

We numerically investigate the stability of solitons in a multimode fiber in the presence of intermodal nonlinear coupling by solving the coupled nonlinear Schrodinger equations. While individual fundamental and higher order solitons propagating in any mode are stable, simultaneous propagation of solitons in different modes leads to interesting phenomena on account of intermodal nonlinear coupling. Soliton trapping is also observed under certain conditions such that two solitons in different modes travel at the same speed despite considerable intermodal differential group delay between them. Finally the effect on launching the solitons at different wavelengths is investigated.