Experimental observation of the spatio-temporal dynamics of breather gases in a recirculating fiber loop

TL;DR

This paper presents the first experimental observation of breather gases in optics within a recirculating fiber loop, demonstrating their formation, dynamics, and statistical properties over 1200 km, aligning with theoretical models.

Contribution

It provides the first experimental evidence of breather gases in optics, validating theoretical predictions and enabling new studies of integrable turbulence with solitons.

Findings

Breather gases form through nonlinear fission in a fiber loop.

Spatiotemporal dynamics match nonlinear Schrödinger equation simulations.

Kurtosis doubles during breather gas evolution.

Abstract

We report the first experimental observation of breather gases (BGs) in optics, realized in a recirculating fiber loop enabling virtually lossless propagation over $1200$ km. Initiated by a slowly modulated optical background perturbed by noise, the BGs form through a nonlinear fission process and demonstrate spatiotemporal dynamics that align closely with numerical simulations of the focusing one-dimensional nonlinear Schr\"odinger equation. The minimal dissipation in our setup enables a statistical characterization of the BGs and confirms the theoretically predicted doubling of kurtosis during the evolution of the BGs. These results open new avenues for experimental studies of integrable turbulence involving solitons on finite background.