Abstract:
In this study, the generalized coupled nonlinear Schr¨odinger-KdV (NLS-KdV) system is
investigated to obtain new optical soliton solutions. This system appears as a model for
reciprocity between long and short waves in various of physical settings. Different kind of
new soliton solutions including dark, bright, combined dark-bright, singular and combined
singular soliton solutions are obtained using two effective methods namely, the extended
sinh-Gordon equation expansion method and the solitary wave ansatz method. In addition,
the modulation instability analysis of the system is presented based on the standard linear-
stability analysis. The behaviours of obtained solutions are expressed by 3D graphs.
