Bright and dark solitary wave soliton solutions for the generalized higher order nonlinear Schrödinger equation and its stability

The higher order nonlinear Schrödinger (NLS) equation describes ultra-short pluse propagation in optical fibres. By using the amplitude ansatz method, we derive the exact bright, dark and bright-dark solitary wave soliton solutions of the generalized higher order nonlinear NLS equation. These solutions for the generalized higher order nonlinear NLS equation are obtained precisely and efficiency of the method can be demonstrated. The stability of these solutions and the movement role of the waves are analyzed by applying the modulation instability analysis and stability analysis solutions. All solutions are exact and stable.