Replica symmetry breaking in a Rayleigh backscattering-based random fiber laser

Abstract

Replica symmetry breaking (RSB) phase transition is observed in disordered photonics systems. The key requirements to observe RSB are provided by random lasers, i.e., gain and disorder. However, in a random fiber laser (RFL) with scattering provided by Rayleigh scattering of light, the condition of quenched disorder is not established due to environment perturbations. Here, RSB is observed in a Rayleigh backscattering-based RFL, where light scattering is due to the inhomogeneity of the optical fiber refractive index. This is done by using short-cavity erbium-RFL with reduced interaction with the environment. Spectral characterization is made, and narrow mode linewidths are demonstrated. The intensity dynamics and laser mode behavior are analyzed showing the presence of gain competition. The results indicate a connection between the replica symmetry or RSB, Lévy-like behavior of intensities, and the presence or not of correlated laser intensity fluctuations.