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

¹ State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications - Beijing 100876, China
² School of Science, Beijing University of Posts and Telecommunications - P. O. Box 122, Beijing 100876, China

^a xinglv655@yahoo.com.cn
^b tian.bupt@yahoo.com.cn

Received: 12 September 2011
Accepted: 21 November 2011

Abstract

In an integrable generalization of the nonlinear Schrödinger 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.