0000000000290652
AUTHOR
Alioune Niang
Spatiotemporal Dynamics in Multimode Nonlinear Optical Fibers
International audience
Multidimensional shaping of spatiotemporal waves in multimode nonlinear fibers
Recent experiments have shown that nonlinear wave propagation in multimode optical fibers leads to complex spatio-temporal phenomena. In this talk, we introduce new approaches for the control and optimization of nonlinear beam reshaping in the spatial, temporal and spectral dimensions. The first approach applies to spatial beam self-cleaning the technique of transverse wavefront shaping, which permits to launch an optimized input mode combination, that results in the stable generation of a whole nonlinear mode alphabet at the fiber output. The second approach introduces a longitudinal tapering of the core diameter of multimode active and passive fibers, which permits to generate ultra-wideb…
Rains of solitons in a figure-of-eight passively mode-locked fiber laser
International audience; We report experimental observation of rains of solitons in figure-of-eight fiber laser passively mode-locked through nonlinear optical loop mirror. Soliton pulses are created from an extended noisy background and drift until they reach a condensed phase comprising several tens of aggregated solitons. The observation of this dynamics tends to strengthen the idea of the universality of the collective behavior of solitons.
Spatial Beam Evolution in Nonlinear Multimode Fibers
We discuss some recent results illustrating the role of input wave-front shaping, propagation dynamics and output beam diagnostics in order to observe spatial beam cleaning in nonlinear multimode fibers and amplifiers.
Manipulating dissipative soliton ensembles in passively mode-locked fiber lasers
International audience; We review our recent experimental and theoretical results addressing the dynamics of large numbers of solitons interacting in presence of a background in passively mode-locked erbium-doped fiber lasers. We first characterize experimentally the soliton rain complex dynamics, and then we focus on ordered soliton patterns. We report that, for suitable experimental parameters, a continuous wave can impose harmonic mode locking. Two levels of modeling for a mode-locked laser subjected to the external injection of a continuous wave are developed to support the latter observation. The first one is based on a scalar master equation, while the second one takes into account th…