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showing 10 items of 4526 documents
Nonlinear phase shift measurement by heterodyne detection in waveguides optics
2022
Nonlinear optics has been a productive field of research and investigation for a few decades now, but the rapid progression of photonic integration platforms in recent years has opened up a whole new range of applications. On-chip integration of effective saturable absorbers and secondary sources including Brillouin laser, supercontinua, or frequency combs are few examples of the very wide possibilities offered by nonlinear nanophotonics. In this context, materials with large third-order optical nonlinearities become highly sought after, as they enable the development of nonlinear functionalities at low input powers. Given a large number of potential candidates as material for nonlinear nan…
Le dioxyde de titane : un matériau nouveau pour la photonique à 1.55 µm et à 2 µm
2018
In the next decades, the limits of current optical communication systems will be reached unless new solutions are adopted. On of them is the use of a new spectral range around 2 µm enabled by the emergence of thulium-doped fiber amplifiers. In this thesis, we will focus on it in the context of very short distances transmissions on photonic chips. Various materials, mainly titanium dioxide (TiO2), will be explored.This thesis work has two main objectives. On the one hand, it aims to demonstrate that a material relatively unexplored, titanium dioxide, is promising for telecom applications by comparing it to more mature plateforms. On the other hand, it tends to introduce the spectral band aro…
Generation of aperiodic picosecond pulses sequences from incoherent optical waves
2007
We present an original method to generate optical pulses trains with random time-interval values from incoherent broadband sources. Our technique relies on the remarkable properties of a line made of cascaded SPM-based optical regenerators.
Vibrating temporal soliton pairs
2007
The study of temporal multisoliton complexes in dissipative systems is of potential interest for the development of new schemes of optical data transport and processing. In the present work, we thus consider pulsations of a soliton pair that consist mainly in the oscillations of the temporal separation and phase relationship between the two pulses, so that the relative motion of the two bound solitons resembles a vibrational motion.
Nonlinear spatial self-cleaning in multimode amplifying fiber and fiber laser cavity
2017
During the last years, multimode fibers (MMFs) were used as an experimental platform for the observation of complex nonlinear propagation phenomena, thanks to their additional spatiotemporal degrees of freedom with respect to single mode fibers. Multimode solitons [1], geometric parametric instability [2], self-induced beam cleaning (SBC) [3] and supercontinuum generation have been reported [4]. In all of these situations considered so far the MMFs were standard graded-index fibers: the intermodal interactions took place in a conservative system (propagation losses were negligible). In this work we have experimentally investigated the Kerr SBC in three dissipative systems: a MMF with signif…
Polarization control in spun and telecommunication optical fibers
2011
International audience; We consider the counterpropagating interaction of a signal and a pump beam in a spun fiber and in a randomly birefringent fiber, the latter being relevant to optical telecommunication systems. On the basis of a geometrical analysis of the Hamiltonian singularities of the system, we provide a complete understanding of the phenomenon of polarization attraction in these two systems, which allows to achieve a control of the polarization state of the signal beam by adjusting the polarization of the pump. In spun fibers, all polarization states of the signal beam are attracted toward a specific line of polarization states on the Poincaré sphere, whose characteristics are d…
Influence of third-order dispersion on the propagation of incoherent light in optical fibers
2010
International audience; We study the influence of third-order dispersion effects on the propagation of an incoherent nonlinear wave in an optical fiber system. The wave spectrum is shown to exhibit a highly asymmetric deformation characterized by a lateral spectral shoulder and the subsequent formation of an unexpected constant spectral pedestal. A kinetic approach to the problem reveals the existence of an invariant that explains in detail the essential properties of such asymmetric spectral evolution of the wave.
Nonlinear optical fiber polarization tracking at 200 krad/s
2011
International audience; We demonstrate endless nonlinear polarization stabilization with a standard telecom fiber at a tracking speed of 200 krads/s. We provide a simple analytical estimate for the response time of nonlinear polarization control
Dissipative Solitons: present understanding, applications and new developments
2009
Dissipative solitons form a new paradigm for the investigation of phenomena involving stable structures in nonlinear systems far from equilibrium. Basic principles can be applied to a wide range of phenomena in science. Recent results involving solitons and soliton complexes of the complex cubic-quintic Ginzburg–Landau equation are presented.
Spatiotemporal optical solitons in nonlinear dissipative media: From stationary light bullets to pulsating complexes
2007
Nonlinear dissipative systems display the full (3+1) D spatiotemporal dynamics of stable optical solitons. We review recent results that were obtained within the complex cubic-quintic Ginzburg-Landau equation model. Numerical simulations reveal the existence of stationary bell-shaped (3+1) D solitons for both anomalous and normal chromatic dispersion regimes, as well as the formation of double soliton complexes. We provide additional insight concerning the possible dynamics of these soliton complexes, consider collision cases between two solitons, and discuss the ways nonstationary evolution can lead to optical pattern formation. © 2007 American Institute of Physics.