Transient soliton dynamics in a mode-locked fiber laser: from stationary to pulsation.

We report the experimental observation of the transformation process from a stationary soliton to a pulsating soliton in a mode-locked fiber laser. The detailed soliton dynamics, including soliton parameter changings and sideband variation in the transition, are analyzed by the dispersive Fourier transformation technique. This Letter unveils the great enhancement of intracavity periodic perturbations resulting from the slight increase of soliton intensity induced soliton modulation instability, leading to the occurrence of parametric sidebands and multi-periodic pulsing instability. Our experimental results can shed some light on the intrinsic mechanism of soliton pulsation, as well as contribute to the study of soliton stability and laser dynamics.