The theoretical study of high-order dissipation soliton molecules evolution in a passively mode-locked fiber laser

Abstract

High-order solitons represent a special form of soliton. Due to the complexity of their spatial structure and dynamic evolution, they have important applications in communication systems such as wavelength division multiplexing and secure communication. However, compared to traditional solitons, research on the spectral evolution of high-order solitons is still insufficient. In this paper, through precise control of laser parameters, the dynamic evolution process from stable dissipative single soliton to complex dissipative 8-order soliton molecules in passively mode-locked fiber lasers was successfully simulated. This demonstrates the complexity of solitons interaction and reveals the regularity of soliton molecules order with variations in four parameters: the small signal gain coefficient, nonlinear coefficient, gain bandwidth and the polarization controller angle. Through deep analysis of the order of soliton molecules, pulse shape and spectral shape of dissipative soliton molecules, we showcase the potential of fine-tuning laser parameters to achieve high-order dissipative soliton molecules. This work provides important references for the optimization design and expanded applications of lasers, further driving the development of high-performance, high-efficiency fiber laser technology.