Dynamics of soliton explosions in passively mode-locked fiber lasers

TL;DR

This study provides a detailed experimental and numerical analysis of soliton explosions in passively mode-locked fiber lasers, revealing how cavity configuration and pump power influence explosion dynamics and introducing the concept of partial explosions.

Contribution

It offers the first detailed experimental and numerical characterization of soliton explosions, including the discovery of partial explosions and their dependence on cavity parameters.

Findings

Explosion frequency can be controlled by pump power.

Explosion characteristics depend on the cavity position of the output coupler.

Numerical simulations agree with experimental results and suggest multi-pulsing instability as a cause.

Abstract

A soliton explosion is an instability whereby a dissipative soliton undergoes a sudden structural collapse, but remarkably returns back to its original shape after a short transient. We recently reported the first experimental observation of this effect in a fiber laser (A. F. J. Runge et al., Optica 2, 36 (2015)). Here, we expand on our initial work, presenting a more detailed experimental and numerical study of the characteristics and dynamics of soliton explosions in passively mode-locked fiber lasers. Specifically, we explore different cavity configurations and gain levels, observing and characterizing explosion events using spectral and temporal real-time single-shot techniques. Our results highlight that the explosion characteristics observed in experiments depend critically on the position in the cavity where the output coupler is located. Furthermore, we find that the frequency at which explosions occur can be controlled by adjusting the pump power. We also identify a new kind of ``partial'' explosion, where strong spectral interference fringes appear on the pulse spectra, but a full collapse is avoided. Finally, we perform numerical simulations based on a realistic iterative cavity map, and obtain results that are in good agreement with experimental measurements. Careful analysis of the simulation results provide strong credence to the interpretation that soliton explosions can be linked to a multi-pulsing instability.