On the study of pulse evolution in ultra-short pulse mode-locked fiber lasers by numerical simulations

In this contribution we highlight several aspects concerning the numerical simulation of ultra-short pulse mode-locked fiber lasers by a non-distributed model. We show that for fixed system parameters multiple attractors are accessible by different initial conditions especially in the transient region between different mode-locking regimes. The reduction of multiple attractors stabilizing from different quantum noise fields to a single solution by gain ramping is demonstrated. Based on this analysis and model, different regimes of mode-locking obtained by varying the intra-cavity dispersion and saturation energy of the gain fiber are revised and it is shown that a regime producing linearly chirped parabolic pulses known from selfsimilar evolution is embedded in the wave-breaking free mode-locking regime. (C) 2007 Optical Society of America