Search results for " Nonlinear Optics"
showing 10 items of 52 documents
Nonlinear repolarization dynamics in optical fibers: transient polarization attraction
2011
International audience; In this work, we present a theoretical and experimental study of the response of a lossless polarizer to a signal beam with a time-varying state of polarization (SOP). By lossless polarizer, we mean a nonlinear conservative medium (e.g., an optical fiber) that is counterpumped by an intense and fully polarized pump beam. Such a medium transforms input uniform or random distributions of the SOP of an intense signal beam into output distributions that are tightly localized around a well-defined SOP. We introduce and characterize an important parameter of a lossless polarizer--its response time. Whenever the fluctuations of the SOP of the input signal beam are slower th…
Linear and nonlinear optical properties of some organoxenon derivatives
2007
We employ a series of state-of-the-art computational techniques to study the effect of inserting one or more Xe atoms in HC2H and HC4H, on the linear and nonlinear optical (L&NLO) properties of the resulting compounds. It has been found that the inserted Xe has a great effect on the L&NLO properties of the organoxenon derivatives. We analyze the bonding in HXeC2H, and the change of the electronic structure, which is induced by inserting Xe, in order to rationalize the observed extraordinary L&NLO properties. The derivatives, which are of interest in this work, have been synthesized in a Xe matrix. Thus the effect of the local field (LF), due to the Xe environment, on the properties of HXeC2…
Designing time and frequency entanglement for generation of high-dimensional photon cluster states
2020
The development of quantum technologies for quantum information science demands the realization and precise control of complex (multipartite and high dimensional) entangled systems on practical and scalable platforms. Quantum frequency combs (QFCs) generated via spontaneous four-wave mixing in integrated microring resonators represent a powerful tool towards this goal. They enable the generation of complex photon states within a single spatial mode as well as their manipulation using standard fiber-based telecommunication components. Here, we review recent progress in the development of QFCs, with a focus on our results that highlight their importance for the realization of complex quantum …
Comprehensive formulation of the temperature dependent dispersion of optical materials; illustration with the case of temperature tuning of a mid-IR …
2009
International audience; The temperature dependence of refractive indices of optical materials is characterized in this work by what we call their normalized thermo-optic coefficients. These ones are determined experimentally through interferometric measurements of thermal expansion, and changes in optical thickness at a few laser wavelengths as function of temperature. A suitable vectorial formalism applied to these data allows predicting the thermal evolution of the refractive index all over the useful range of transparency. The validity and reliability of our methodology is demonstrated through temperature tuning of a mid-IR HgGa2S4 OPO, pumped at 1.0642 μm by a Nd:YAG laser. Measured the…
Analytical Dynamics of Optical Similaritons
2007
We analytically describe the attraction of parabolic pulses towards a self-similar state in weakly dispersive nonlinear fibers with linear gain.
Optical peregrine soliton generation in standard telecommunication fibers
2011
By combining real time characterization with cut-back measurements, we provide the first direct observation of Peregrine-like soliton longitudinal evolution dynamics and report a new effect associated with the breakup of a Peregrine soliton into two subpulses, each providing similar characteristics of localization upon finite background. Experimental results are in good agreement with simulations.
Entanglement between two superconducting qubits via interaction with nonclassical radiation
2003
We propose a scheme to physically interface superconducting nano-circuits and quantum optics. We address the transfer of quantum information between systems having different physical natures and defined in Hilbert spaces of different dimensions. In particular, we investigate the transfer of the entanglement initially in a non-classical state of a continuous-variable system to a pair of superconducting charge qubits. This set-up is able to drive an initially separable state of the qubits into an almost pure, highly entangled state suitable for quantum information processing.
Spatiotemporal light-beam compression from nonlinear mode coupling
2017
We experimentally demonstrate simultaneous spatial and temporal compression in the propagation of light pulses in multimode nonlinear optical fibers. We reveal that the spatial beam self-cleaning recently discovered in graded-index multimode fibers is accompanied by significant temporal reshaping and up to four-fold shortening of the injected sub-nanosecond laser pulses. Since the nonlinear coupling among the modes strongly depends on the instantaneous power, we explore the entire range of the nonlinear dynamics with a single optical pulse, where the optical power is continuously varied across the pulse profile.
Probing ultrafast thermalization with field-free molecular alignment
2012
International audience; The rotation-translation thermalization of CO2 gas is investigated 500 ps after its preheating by a nonresonant short and intense laser pulse. The temperature of thermalization is optically determined with two additional short laser pulses enabling a field-free molecular alignment process and its probing, respectively. The measurements are performed for various intensities of the preheat pulse, leading to the observation of different temperatures which are in very good agreement with classical molecular dynamics simulations. The results can be regarded as a step towards real-time tracking of ultrafast relaxation pathways in molecular motion.
Analyse statistique de la phase des solitons optiques
2005
On analyse numeriquement la statistique de la phase des solitons optiques et on arrive a determiner la fonction de densite de probabilite. Nos resultats sont en accord avec les theories existantes, qui sont basees sur les proprietes des solitons.