Novel behavior and properties for the nonlinear pulse propagation in optical fibers

In an integrable generalization of the nonlinear Schrodinger equation for nonlinear pulse propagation in monomode optical fibers, certain higher-order nonlinear effects are taken into account. Hereby for such a model, our investigation focuses on the following aspects: a) modulation instability analysis of solutions in the presence of a small perturbation; b) derivation of the infinite conservation laws based on the Lax pair; c) soliton solutions obtained in virtue of the bilinear method with symbolic computation; d) asymptotic analysis and graphical illustration of the solitons. With different choices of the wave numbers in the two-soliton solutions, solitonic characteristics has been discussed. Finally a new type of soliton, namely the "earthwormon", has been proposed in that the moving two-soliton structure looks like an earthworm in slice graphics. Copyright (C) EPLA, 2012