Energy disturbance-induced collision between soliton molecules and switch dynamics in fiber lasers: periodic collision, oscillation and annihilation

The collision dynamics of soliton molecules (SMs) demonstrate significant complexity. In this study, a carbon black/graphene oxide composite material is utilized as a saturable absorber. By enabling precise control of intracavity polarization and loss states, it is demonstrated that soliton molecule collisions can effectively function as switches for different soliton states. Post-collision energy perturbations destabilize the equilibrium between nonlinear and dispersive effects, leading to phenomena including periodic collisions, oscillations, and soliton annihilation. Theoretical simulations reveal the mechanism of state switching driven by soliton collisions and show that precise control over collision processes and subsequent state transitions can be achieved by tuning small-signal gain, pulse saturation energy, and second-order group velocity dispersion. These findings provide what we believe to be novel perspectives for the optimization of nonlinear optical devices and the study of soliton dynamics.