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arXiv · 2503.13030

Perturbed Nonlinear Evolution of Optical Soliton Gases: Growth and Decay in Integrable Turbulence

Loic Fache·Francois Copie·Pierre Suret·Stéphane Randoux
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Abstract

We present optical fiber experiments investigating the perturbed, non-integrable evolution of soliton gases (SGs) under weak linear damping and gain. By measuring the amplitude and phase of the optical field in a recirculating loop, we determine the spectral distribution of SGs at various propagation distances. We demonstrate that a SG, initially prepared as a soliton condensate with a Weyl distribution, undergoes significant changes in its spectral distribution due to dissipation. Specifically, weak gain leads to the emergence of a nearly monochromatic SG, while weak damping results in a SG with a semicircular spectral distribution at long propagation distances. These observed dissipation-driven changes in the SG's spectral characteristics are not explained by existing hydrodynamic or kinetic theories.

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Loic Fache, Francois Copie, Pierre Suret, Stéphane Randoux. 2025-03-17. Perturbed Nonlinear Evolution of Optical Soliton Gases: Growth and Decay in Integrable Turbulence. https://arxiv.org/abs/2503.13030

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