Soliton aspects of the inhomogeneous coupled nonlinear Schrödinger equation in optical fibre

The inhomogeneous coupled nonlinear Schrödinger (ICNLS) equations which describe the propagation of two fields in a nonuniform fibre medium are considered. The integrable forms of the ICNLS equation are identified from the Painlevé singularity structure analysis. The variable transformations which connect the integrable forms of the ICNLS equation and the coupled nonlinear Schrödinger equations (CNLS) are presented. With the help of the linear eigenvalue problem and Bäcklund transformation, a single-soliton solution is generated explicitly.