Unveiling soliton booting dynamics in ultrafast fiber lasers

TL;DR

This paper investigates the detailed buildup process of ultrafast soliton pulses in fiber lasers, revealing different dynamics in anomalous and normal dispersion regimes through advanced experimental and theoretical methods.

Contribution

It provides the first comprehensive analysis of soliton booting dynamics in ultrafast fiber lasers using spatio-temporal reconstruction and dispersive Fourier transform techniques.

Findings

Different booting dynamics for conventional and dissipative solitons.

Spectral interference patterns with relaxation oscillations observed near mode-locking.

Transient structured soliton formation influences spectral pattern distributions.

Abstract

Ultrafast fiber lasers play important roles in many aspects of our life for their various applications in fields ranging from fundamental sciences to industrial purposes. Passive mode-locking technique is a key step to realize the ultrafast soliton fiber lasers. However, the booting dynamics of the soliton fiber lasers have not yet been well understood. Herein, we reveal the soliton buildup dynamics of ultrafast fiber lasers operating both in anomalous and net-normal dispersion regimes. Based on the advanced experimental methodologies of spatio-temporal reconstruction and dispersive Fourier transform (DFT), the soliton booting dynamics are analyzed in the time and spectral domains. It was found that the booting dynamics of conventional and dissipative solitons operating in the anomalous and net-normal dispersion regimes, respectively, are different from each other due to the different pulse shaping mechanisms. In particular, the spectral interference pattern with strong relaxation oscillation behavior was observed near the mode-locking transition for conventional soliton, while no relaxation oscillation of spectral pattern was obtained for dissipative soliton. We firstly revealed that the spectral pattern distributions are induced by the transient structured soliton formation during the pulse shaping from the noise background. The experimental results were verified by the theoretical simulations. The obtained results would provide a general guideline for understanding the soliton booting dynamics in ultrafast fiber lasers, and will prove to be fruitful to the various communities interested in solitons and fiber lasers.