0000000000011174

AUTHOR

Ph. Grelu

Dark spatial solitary waves in a cubic-quintic-septimal nonlinear medium

We consider the evolution of light beams in nonlinear media exhibiting nonlinearities up to the seventh order wherein the beam propagation is governed by the cubic-quintic-septimal nonlinear Schr\"odinger equation. An exact analytic solution that describes dark solitary wave propagation is obtained, based on a special ansatz. Unlike the well-known $\text{tanh}$-profile dark soliton in Kerr media, the present one has a functional form given in terms of ``${\text{sech}}^{2/3}$''. The requirements concerning the optical material parameters for the existence of this localized structure are discussed. This propagating solitary wave exists due to a balance among diffraction, cubic, quintic, and s…

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Dipole soliton solution for the homogeneous high-order nonlinear Schrödinger equation with cubic–quintic–septic non-Kerr terms

Abstract We consider a high-order nonlinear Schrodinger equation with third- and fourth-order dispersions, cubic–quintic–septic nonlinearities, self-steepening, and instantaneous Raman response. This equation models describes ultra-short optical pulse propagation in highly-nonlinear media. The ansatz solution of Choudhuri and Porsezian (in Ref. [16]) is adapted to investigate solutions composed of the product of bright and dark solitary waves. Parametric conditions for the existence of the derived soliton solutions are given and their stabilities are numerically discussed. These exact solutions provide insight into balance mechanisms between several high-order nonlinearities of different na…

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Near-field control of optical bistability in a nanocavity

Micro- and nanocavities allow for strong light confinement in very small volume [1]. They give opportunities for new experiments such as cavity quantum electrodynamics, waveguiding, light slowing or trapping…[2] The increase of the electromagnetic (EM) field in the cavity enhances the interaction between light and matter, resulting in the possible observation of nonlinear effects [3]. Several studies have recently been published on the observation and characterisation of nonlinear silicon cavities [4]. As a step further, we propose and demonstrate the feasibility of an innovative way to mechanically control the bistable operating regime of a nanovavity. Using a near-field tip, we switch the…

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Sub-nanosecond nonlinear pulse shaping in microfiber resonators

Thanks to their small size and large index contrast allowing for tight field confinement, optical microfibers are of great interest in nonlinear optics. Their properties have recently been exploited in various devices for supercontinuum generation, pulse compression [1] and third-harmonic generation [2]. Combining field confinement and field enhancement in a loop or knot resonator can result in low-threshold non-linear microfibre devices, in which pulse shaping effects and bistability can be obtained. Such a behaviour has already been observed at a power level of ten milliwatts with millisecond time response, in the case of thermally-induced non-linearity in silica microfibres [3]. In contr…

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Phase-locked soliton pairs in a stretched-pulse fiber laser.

We report the experimental observation of stable pulse pairs with a ±π/2 phase difference in a passively mode-locked stretched-pulse fiber ring laser. In our setup the stabilization of interacting subpicosecond pulses is obtained with a large range of pulse separations, namely, from 2.7 to 10 ps, without the need for external control. © 2002 Optical Society of America

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Multisoliton states and pulse fragmentation in a passively mode-locked fibre laser

We report the observation of a novel feature in the pulse emission characteristics of a passively mode-locked fibre ring laser. In both anomalous and normal path-averaged dispersion regimes, we show switching from stationary multisolitons, which comprise a small number of pulses, to large soliton trains. The abrupt transition between the two emission regimes is manifested in both ways. © 2004

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Pulsating Dissipative Light Bullets

Finding domains of existence for (3+1)D spatio-temporal dissipative solitons, also called “dissipative light bullets”, by direct numerical solving of a cubic-quintic Ginzburg-Landau equation (CGLE) is a lengthy procedure [1,2]. Variational approaches pave the way for quicker soliton solution mapping, as long as tractable trial functions remain suitable approximations for exact solutions [3,4].

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Potentialités des lasers à fibre dans la génération de rayonnement cohérent UV

Le premier laser a fibre dope aux ions de terres rares fonctionna au tout debut des annees 60. Il fournissait quelques milliwatts autour de 1 μm. Les decades suivantes virent tres peu d'ameliorations tant du cote des laboratoires que du point de vue industriel. La derniere decennie (1995/2005) vit se concretiser la seconde revolution des lasers a fibres. Deja kilowatt en continu, ils atteignent desormais les 10 13 watts/cm 2 avec des impulsions de la centaine de femtoseconde. Lors de cette presentation nous passerons en revue les potentialites des lasers a fibre. Nous decrirons les verrous technologiques qui ont ete leves ces dix dernieres annees pour les regimes CW mais aussi femtosecondes…

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Complexes and Molecules of Dissipative Solitons in Mode-Locked Lasers

Pulse-pulse interaction is a major issue in the development of high-repetition rate fiber laser sources or soliton-based optical transmission lines. The design of a suitable level of nonlinear dissipation, through nonlinear filters or saturable absorbers for instance, is able to improve significantly the stability of multiple pulse operation. The concept of a dissipative soliton has become an important tool for the exploration and the analysis of the multiple pulse dynamics, with mode-locked lasers and regenerated transmission lines as important applications [1,2]. Above all, the study of dissipative solitons has become a fertile area of nonlinear science with multidisciplinary implications…

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phase-locked soliton pairs in a fiber ring laser

We have experimentally observed the formation of stable pulse pairs with a π/2 phase difference in a passively mode-locked stretched-pulse fiber ring laser. We have developed a simplified theoretical model that, keeping the essential features of the experiment, reduces greatly the number of free parameters and solved it numerically. The agreement with the experimental results is excellent.

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Stationary and Pulsating Dissipative Optical Bullets

We demonstrate the existence of stable optical light bullets in nonlinear dissipative media. Beyond the domain where stable bullets are found, unstable bullets show unusual behaviors, like "optical rockets", pulsating solutions or pattern formation.

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Regions of Existence and Transformations of (3+1)-D Dissipative Optical Solitons

We demonstrate the existence of stable optical light bullets in nonlinear dissipative media featuring both normal and anomalous chromatic dispersion. Beyond the domain where stable bullets are found, unstable bullets can be transformed into "rockets".

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Soliton pairs in a fiber laser: From anomalous to normal average dispersion regime

We report the observation of self phase-locked pulse pairs in a stretched-pulse fiber laser operating in the normal path-averaged dispersion regime. Numerical simulations agree with our experimental results. More insight is provided with a numerical comparison between intracavity profiles of pulse pairs in anomalous and in normal dispersion regimes. © 2003 Optical Society of America.

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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…

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Dissipative solitons for mode-locked fiber lasers

The concept of a dissipative optical soliton is applied to interpret various pulse dynamics either predicted numerically or observed experimentally in passively mode-locked fiber lasers. The recently discovered “dissipative soliton resonance” phenomenon and “soliton rain” dynamics are highlighted as prominent examples.

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Rogue waves among noiselike-pulse laser emission: An experimental investigation

We investigate experimental conditions in a fiber ring laser where noiselike-pulse emission fulfills the rogue wave criteria, highlighting the influence of the chromatic dispersion sign as well as the pivotal role of the pulse measurement design. While pulse-energy rogue waves are exclusively detected in the anomalous dispersion regime, spectral rogue waves are recorded for both positive and negative dispersions. To reveal $\mathsf{L}\text{-shaped}$ statistical series compatible with the generation of spectral rogue wave events, the dispersive Fourier-transform method is implemented to study the shot-to-shot spectral fluctuations of the laser output.

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Dissipative shock waves in all-normal-dispersion mode-locked fiber lasers

4 pags.; 4 figs.; OCIS codes: (140.4050) Mode-locked lasers; (140.3510) Lasers, fiber.

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Stabilisation of modelocking in fibre ring laser through pulse bunching

Bunching of equally spaced pulses is reported to be the most stable mode of operation in a passively modelocked fibre ring laser. The ring includes dispersion management, which results in the absence of strict pulse energy quantisation, giving pulse bunching a better immunity to environmental perturbation.

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Optical Soliton Molecules in Fiber Lasers

Recent experiments demonstrate that fiber laser cavities are able to support various multisoliton complexes, analogous to soliton molecules, which could have impact on optical information transmission or storage. These advances are guided by the concept of dissipative soliton.

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Stationary and pulsating dissipative light bullets from a collective variable approach

A collective variable approach is used to map domains of existence for (3+1) -dimensional spatiotemporal soliton solutions of a complex cubic-quintic Ginzburg-Landau equation. A rich variety of evolution behaviors, which include stationary and pulsating dissipative soliton dynamics, is revealed. Comparisons between the results obtained by the semianalytical approach of collective variables, and those obtained by a purely numerical approach show good agreement for a wide range of equation parameters. This also demonstrates the relevance of the semianalytical method for a systematic search of stability domains for spatiotemporal solitons, leading to a dramatic reduction of the computation tim…

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