Influence of higher-order stimulated Brillouin scattering on the occurrence of extreme events in self-pulsing fiber lasers

We investigate the dynamical behavior of a self-pulsing laser under the influence of stimulated Brillouin scattering (SBS), a system which has previously been shown to favor extreme statistics. Using a laser model coupling a multi-Stokes Brillouin scattering process with the population inversion formalism for the gain and taking into account saturable absorption effects, we demonstrate that different statistical distribution types arise as the nonlinear interactions between the laser and higher-order SBS waves lead to the occurrence of high intensity short pulses. By taking into account up to five Stokes orders, we show that highly skewed statistics and pulses with extreme peak intensities can be obtained, allowing us to describe more accurately the experimental observations and to better apprehend the underlying physics.We also unexpectedly demonstrate that the acoustic noise does not affect the emergence of such extreme events

Experimental observation of a cyclic dynamics of solitons in a fiber laser

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Extreme events generation via cascaded stimulated Brillouin scattering in self-pulsing fiber lasers

International audienceExtreme-amplitude events and rare instabilities are observed for more than a decade in various optical systems. Specifically in dissipative systems, such as Raman fiber lasers, laser diodes or mode-locked lasers, to name a few, long-tailed statistics and highly-localized temporal structures have been observed [1,2]. Recent studies showed that stimulated Brillouin scattering (SBS) can also trigger the generation of extreme events in various configurations, from self-pulsing fiber lasers [3,4] to Q-switched random fiber lasers [5]. It is indeed known that the stochastic nature of SBS can promote the emergence of randomly distributed giant pulses which can induce irreversible damages in fiber laser systems. In order to understand and open the possibility to harness such extreme events, numerical models have then to be developed and refined. In the context of self-pulsed fiber lasers, a few studies taking into account only one or two fundamental Stokes orders have already been reported [6]. Such models describe well the large pulse-to-pulse intensity fluctuations observed in Erbium-doped fiber lasers Q-switched through SBS but they however did not predict any extreme event [6]. We propose here an extension of the model proposed in Ref. [3] by generalizing it to higher Stokes orders to study their impact on extreme dynamics in a self-pulsing laser. Our model is based on the coupled amplitudes equations describing the spatiotemporal dynamics of both the laser and Brillouin waves with their corresponding acoustic fields, as well as the temporal variations of the gain for each wave. We also consider a matter equation to account for the saturable absorption effect which can occur in the un-pumped segment of the active fiber. We show that increasing the number of SBS orders interacting with the gain medium reveals new dynamics enabling the generation of extreme events which are not predicted by the single SBS order model. Pulses with amplitudes 27 times the so-called signific..

Extreme events generation via cascaded stimulated Brillouin scattering in self-pulsing fiber lasers

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Influence of stimulated Brillouin scattering on the dynamics of a self-pulsing fiber laser

International audienc

Influence of stimulated Brillouin scattering on the dynamics of a self-pulsing fiber laser

International audienc

Influence of stimulated Brillouin scattering on the dynamics of a self-pulsing fiber laser

International audienc