Spatial soliton scattering in a quasi phase matched quadratic media in presence of cubic nonlinearity

We consider the propagation, fusion and scattering of solitary pulse in a quasi phase mached quadratic media in presence of cubic nonlinearity. The chief motivation is to analyze the mutual influence of phase matching, quadratic and cubic nonlinearities in the evolution of solitary pulse and its robustness. It is observed that the scenario of scattering changes considerably due to the presence of cubic nonlinearity, which is seen to favour the event of trapping of the pulses and their fusion is more favoured in the purely quadratic situation. The basic properties of the pulses, such as width, chirp etc. are also analyzed during their propagation along the fibre. The behaviour of these parameters is seen to be more controlled only in presence of cubic nonlinearity. Lastly we have also studied with some periodic amplification in the system. In this situation the QPM (quasi phase matched) system in absence of cubic term shows much better behaviour.