WorldCat Identities

Amy-Klein, Anne

Overview
Works: 23 works in 34 publications in 2 languages and 46 library holdings
Roles: Thesis advisor, Opponent, Other, Author, 956, Contributor
Publication Timeline
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Most widely held works by Anne Amy-Klein
Etude structurale de biomolécules de grandes tailles, en phase gazeuse, par spectroscopie infrarouge, spectrométrie de mobilité ionique et dissociation induite par attachement d'électron by Thi Ngà Lê( Book )

3 editions published in 2014 in French and held by 4 WorldCat member libraries worldwide

Gas-phase studies of large biological molecules have emerged with the advent of soft production methods of biomolecular ions under vacuum (like ESI or MALDI) combined to mass spectrometry. The first aim of this work was to use three complementary experimental techniques, namely IRMPD spectroscopy, ion mobility mass spectrometry and electron capture dissociation ECD to probe the gas-phase structures of amyloïd A[beta]₁₂-₂₈ and tryptophan zippers TZ1 and TZ4 peptides. The main originality of this study is to analyse the specific c/z product ion abundances in ECD experiments with the structural information gained through IR spectroscopy and ion mobility experiments. With this complementary approach, we were able to assign the most probable gas-phase structures of these flexible peptides. In particular, it is shown that the native structure of the peptides is not conserved in the gas phase. This study relies on the interplay between experiments and theoretical calculations. To that end, we used several theoretical methods, ranging for molecular dynamics using a classical force field (AMBER) to quantum mechanics calculations to simulate the vibrational spectra of the peptides. The second aim of this work was to design, develop and optimize a unique device, coupling a novel source introducing biomolecules in the gas phase, based on laser desorption from liquid micro-droplets directly into vacuum, coupled with a time-of-flight mass spectrometer. This desorption source is an original alternative to the usual methods (ESI or MALDI). Through mass spectrometry techniques, it should allow investigating the complexation processes of non-covalently bound species in conditions as close as the ones encountered in solution. We have recently obtained the first mass spectra. Due to the high velocity spread of the desorbed ions, new developments are needed to improve the mass resolution. In particular, we plan to transfer the ions in a quadrupole ion trap and to perform the laser desorption in front a pulsed valve to stream the ions in the supersonic expansion
Transfert à très haute résolution d'une référence de fréquence ultra-stable par lien optique et application à la stabilisation d'un laser moyen-infrarouge by Bruno Chanteau( Book )

3 editions published in 2013 in French and held by 4 WorldCat member libraries worldwide

Ce manuscrit présente le transfert d'une référence de fréquence optique ultra-stable à un lien optique et son application à la stabilisation en fréquence d'un laser moyen-infrarouge. Un lien optique permet de transférer une fréquence ultra-stable par fibre optique sans dégrader sa stabilité grâce à une compensation du bruit apportée lors de la propagation. Nous avons étendu cette technique à des liens de grande longueur en transférant la référence de fréquence simultanément avec les données du réseau Internet. Ainsi des liens de 300 km puis 540 km ont été démontrés avec une stabilité de l'ordre de 10⁻ ¹⁹ à 10⁴ s. Ce dispositif à été utilisé au LPL pour asservir un laser CO² émettant à 10 µm sur une référence de fréquence développée au LNE-SYRTE, à l'Observatoire de Paris. Celle-ci est constituée d'un laser ultra-stable émettant à 1,54 µm, dont la fréquence est mesurée par rapport aux étalons primaires du LNE-SYRTE grâce à un laser femtoseconde. Cette référence est transférée par un lien optique jusqu'au LPL où elle permet de stabiliser la fréquence de répétition d'un second laser femtoseconde et de mesurer ou contrôler la fréquence d'un laser CO² . Lorsque celui-ci est asservi sur une référence moléculaire (OsO₄), la stabilité est de 4.10⁻¹⁴ à 1 s. Les performances sont encore meilleures lorsque le laser CO² est asservi directement sur la référence optique. Le laser stabilisé pourra ensuite être utilisé pour l'expérience d'observation de la violation de parité dans les molécules chirales développées au LPL. Ceci démontre la faisabilité d'expériences de spectroscopie moléculaire à ultra haute résolution dans les laboratoires ne disposant pas d'étalons de fréquence
Développement de liens optiques ultra-stables pour le transfert de fréquences à longues distances velopment of ultra-stable laser sources and long-distance optical link via telecommunication networks by haifeng Jiang( )

2 editions published in 2010 in French and English and held by 4 WorldCat member libraries worldwide

The transfer of ultra-stable frequencies between distant laboratories is required by many applications in time and frequency metrology, fundamental physics, particle accelerators and astrophysics. This thesis describes the development of ultra-stable optical links over distances from 86 km to 300 km. The long-term objective is to connect the main European National Metrology Institutes with optical links extending up to 1000 km. The optical link is based on the transfer of the optical phase of an ultra-stable laser emitting light of wavelength 1542 nm through an optical fiber of the telecommunication network. For that purpose, ultra-stable cavity-stabilized lasers and fiber-stabilized lasers have been developed. The fractional instability of cavity-stabilized laser is approximately 10-15 at 1s integration time. The fiber-stabilized lasers are robust, compact, simple, tunable and their frequency noise is comparable to that of the cavity-stabilized laser for Fourier frequencies higher than a few tens of Hertz. Optical links were first demonstrated on 86 km and 172 km using dedicated fibers connecting the laboratories LNE-SYRTE and LPL. Fractional frequency instability in the range of or below 10-19 at 104 s integration time has been obtained. For larger distances, the ultra-stable laser signal is transferred on the Internet network simultaneously with the data traffic but on a dedicated frequency channel, using wavelength division multiplexing. Multiplexed links were demonstrated over distances up to 300 km, with fractional frequency instabilities at the same level or better than with dedicated fibers
Jet lent d'atomes d'argon métastables pour l'étude de l'échange de métastabilité, des interactions de van der Waals et des milieux d'indice négatif. by Thierry Taillandier-Loize( Book )

3 editions published in 2014 in French and held by 4 WorldCat member libraries worldwide

La thématique abordée dans cette thèse relève de la manipulation d'un jet d'atomes d'argon métastables (Ar* ³P2) dans différentes configurations. Premièrement, je présente l'échange de métastabilité entre un atome au fondamental et un atome excité à de faibles énergies de centre de masse (entre 4 et 9 meV). Je propose également l'interprétation théorique par une approche semi-classique (approximation JWKB) qui se révèle validée, dans ce domaine d'énergies, en comparaison avec la résolution exacte de l'équation de Schrödinger radiale mettant en jeu les potentiels concernés par la collision. Les sections efficaces absolues d'échanges, déduites d'une analyse en temps de vol du signal métastable, permettent de réaliser une comparaison sans biais avec les prédictions théoriques. Les caractéristiques d'un jet ralenti par effet Zeeman sont dégradées par le processus de ralentissement et le rende difficilement utilisable en deçà de quelques dizaines de mètres par seconde. C'est pourquoi, dans un deuxième temps, je présente la réalisation d'un jet lent original, issu d'un piège magnéto-optique et présentant des caractéristiques remarquables. La vitesse est accordable entre 10 et 100 m/s, la dispersion de vitesse relative est très faible (6 % à 20 m/s) et le flux est conséquent (10⁹ Ar*/s/sr), pour une ouverture angulaire standard (35 mrad FWHM). Ce nouveau dispositif permet de présenter certaines questions d'interférométrie et d'optique atomique telles que les interactions atome-surface de type van der Waals et l'étude de potentiels comobiles ainsi que leurs applications dans la réalisation de milieux d'indice négatif ou de ralentisseurs
Spectroscopie à très haute résolution de molécules sublimées en jet supersonique : vers une observation de la non conservation de la parité dans les molécules chirales par spectroscopie laser by Clara Stoeffler( Book )

2 editions published in 2011 in French and held by 3 WorldCat member libraries worldwide

The work presented in this manuscript consisted in the elaboration and optimisation of an experimental set up dedicated to the observation of parity violation (PV) in a supersonic beam of chiral molecules. Remarkably enough, the molecules considered which are currently being synthesized are in the solid phase at 300 K. We thus built a set up which enables to obtain a vapour phase of the molecules of interest by heating to realise a supersonic expansion via a pickup method with helium as a carrier gas. Furthermore, we used a time of flight technique to detect and estimate the amount of seeded molecules. We tested our set up with methyltrioxorhenium (MTO), a molecule from which chiral derivatives are being synthesized. We built up an experimental procedure to obtain the spectral characteristics and molecular parameters of the studied molecule. For that purpose we used saturated absorption spectroscopy in a cell at 300 K. Then a supersonic expansion of MTO in helium was obtained showing very good results. Indeed a ~10% molar fraction of MTO could be reached. Finally we recorded linear absorption spectra of MTO in beam on the experimental set up dedicated to the PV observation using a multi pass cell. The experimental data analysis enabled to simulate the theoretical spectrum of MTO. These results are very promising results with respect to the future experiments planned with chiral molecules
Développement de liens optiques ultra-stables pour le transfert de fréquences à longues distances = velopment of ultra-stable laser sources and long-distance optical link via telecommunication networks by haifeng Jiang( Book )

2 editions published in 2010 in English and held by 3 WorldCat member libraries worldwide

The transfer of ultra-stable frequencies between distant laboratories is required by many applications in time and frequency metrology, fundamental physics, particle accelerators and astrophysics. This thesis describes the development of ultra-stable optical links over distances from 86 km to 300 km. The long-term objective is to connect the main European National Metrology Institutes with optical links extending up to 1000 km. The optical link is based on the transfer of the optical phase of an ultra-stable laser emitting light of wavelength 1542 nm through an optical fiber of the telecommunication network. For that purpose, ultra-stable cavity-stabilized lasers and fiber-stabilized lasers have been developed. The fractional instability of cavity-stabilized laser is approximately 10-15 at 1s integration time. The fiber-stabilized lasers are robust, compact, simple, tunable and their frequency noise is comparable to that of the cavity-stabilized laser for Fourier frequencies higher than a few tens of Hertz. Optical links were first demonstrated on 86 km and 172 km using dedicated fibers connecting the laboratories LNE-SYRTE and LPL. Fractional frequency instability in the range of or below 10-19 at 104 s integration time has been obtained. For larger distances, the ultra-stable laser signal is transferred on the Internet network simultaneously with the data traffic but on a dedicated frequency channel, using wavelength division multiplexing. Multiplexed links were demonstrated over distances up to 300 km, with fractional frequency instabilities at the same level or better than with dedicated fibers
Conjugaison de phase et mélange d'ondes multi-résonnant en phase vapeur, dans le domaine visible et ultra-violet by Anne Amy-Klein( Book )

2 editions published in 1990 in French and held by 3 WorldCat member libraries worldwide

Ce travail présente diverses études de mélanges d'ondes en milieu gazeux résonnant. La plupart des expériences utilisent une source laser ultraviolette continue, monomode et balayable en fréquence, obtenue par doublage intra-cavité d'un laser a colorant. Nous étudions d'abord le comportement de saturation du mélange résonnant a quatre ondes quasi dégénéré en fréquence avec l'avant: les prédictions théoriques, aussi bien que des expériences sur la raie de résonance infrarouge de la vapeur de césium, montre que dans le cas d'un systeme a deux niveaux le dédoublement Stark est apparent dans les formes de raies. Le comportement se révèle analogue dans l'extension au mélange multi-ondes. Nous présentons ensuite une expérience de spectroscopie par absorption saturée de la raie de résonance u.v. Du magnésium (285 nm), qui fournit une nouvelle détermination de l'écart isotopique. Sur cette même raie, nous avons également obtenu un signal de conjugaison de phase en continu dans l'u.v. Par mélange a quatre ondes dégénéré vers l'arrière. La difficulté de l'expérience provient de la puissance limitée de la source signal proportionnel au cube de l'intensité sonde et de l'intensité de saturation relativement élevée de la transition. Nous décrivons aussi des expériences de spectroscopie de saturation et de mélange d'ondes sur des systèmes résonnants à trois niveaux couplant une transition u.v. Et une transition visible, et analysons les différentes dépendances par rapport a l'intensité u.v. Nous discutons finalement des possibilités d'imagerie avec conversion de fréquence, et notamment de conjugaison de phase avec doublage de fréquence
Ultrastable optical frequency dissemination on a multi-access fibre network by Anthony Bercy( )

1 edition published in 2016 in English and held by 2 WorldCat member libraries worldwide

Spectroscopie à très haute résolution de molécules sublimées en jet supersonique vers une observation de la non conservation de la parité dans les molécules chirales par spectroscopie laser by Clara Stoeffler( )

1 edition published in 2011 in French and held by 2 WorldCat member libraries worldwide

The work presented in this manuscript consisted in the elaboration and optimisation of an experimental set up dedicated to the observation of parity violation (PV) in a supersonic beam of chiral molecules. Remarkably enough, the molecules considered which are currently being synthesized are in the solid phase at 300 K. We thus built a set up which enables to obtain a vapour phase of the molecules of interest by heating to realise a supersonic expansion via a pickup method with helium as a carrier gas. Furthermore, we used a time of flight technique to detect and estimate the amount of seeded molecules. We tested our set up with methyltrioxorhenium (MTO), a molecule from which chiral derivatives are being synthesized. We built up an experimental procedure to obtain the spectral characteristics and molecular parameters of the studied molecule. For that purpose we used saturated absorption spectroscopy in a cell at 300 K. Then a supersonic expansion of MTO in helium was obtained showing very good results. Indeed a ~10% molar fraction of MTO could be reached. Finally we recorded linear absorption spectra of MTO in beam on the experimental set up dedicated to the PV observation using a multi pass cell. The experimental data analysis enabled to simulate the theoretical spectrum of MTO. These results are very promising results with respect to the future experiments planned with chiral molecules
Simultaneous remote transfer of accurate timing and optical frequency over a public fiber network by Olivier Lopez( )

1 edition published in 2012 in English and held by 2 WorldCat member libraries worldwide

Hybrid fiber links for accurate optical frequency comparison by Won-Kyu Lee( )

1 edition published in 2017 in English and held by 2 WorldCat member libraries worldwide

Développement de cavités Fabry-Perot ultra-stables pour références de fréquence optique de nouvelle génération by Alexandre Didier( Book )

2 editions published in 2016 in French and held by 2 WorldCat member libraries worldwide

The work described in this document deals with optical frequency references, or ultrastable lasers. They are obtained from the frequency locking of a laser on a high finesse Fabry-Perot cavity. A first laser is stabilized on a commercial ULE Fabry-Perot cavity and exhibits a 1:9 x10-15 fractional frequency instability at 1 s. A femtosecond laser is phased lock to this ultrastable laser and allows generating an ultra-pure microwave signal. At 10 GHz, the signal exhibits a -104 dBc/Hz phase noise at 1 Hz. In a second project, we design a 25 mm ultra-compact cavity. Extensive finite element modeling led to a new spacer geometry, with simulated acceleration sensitivities below 10-12=(m=s2) in all directions. A compact vacuum chamber with embedded optical set-up has been developed to reduce the size of the system. Finally, a cryogenic silicon cavity has been designed. It will be cooled down to 17 K. At this temperature, its thermal noise would limit its fractional frequency instability to3 x 10-17. A low vibration cryogenerator is used to reach this temperature. Finite element modeling led to 4:5x 10-12=(m=s2) acceleration sensitivity
Résonance noire à trois photons sur un nuage d'ions calcium confinés by Mathieu Collombon( )

1 edition published in 2019 in French and held by 1 WorldCat member library worldwide

The work presented in this thesis describes the complete experimental set-up and approach to realize three-photon coherent population trapping in a cloud of radiofrequency confined calcium ions. The realization of such a population trapping relies on a stringent conditions of the phase relationship between the three lasers involved in the interrogation process, and also their spectral linewidths. Our experimental approach is based on the optimization of the performance of a frequency-stabilized titanium-sapphirelaser at 411 THz (729nm) at the 10⁻¹⁴ level, in term of relative frequency uncertainties. This laser's fre-quency stability is subsequently transfered to a optical frequency comb by means of a phase-locked loop. Then the two other lasers involved (866 nm and 794 nm) are phase-locked to the optical frequency combwith the same technique. This work describes the transfer method along with its measured performances. With all the three lasers sharing the same ultra-stable frequency reference we have been able to experi-mentally observe for the first time a 3-photon dark resonance in the fluorescence spectra of the 40 Ca⁺, signature of a coherent population trapping in a 3-photon scheme. The dependence of this resonance at experimental parameters, such as laser powers, laser detunings and local magnetic field, have been studied and are presented in this work. The preliminary results have allowed to explain the behaviour of the dark resonance and explored conditions for the use of the 3-photon dark line as a THz frequency standard
Génération de peignes de fréquences par modulation électro-optique et applications by Alexandre Parriaux( )

1 edition published in 2020 in French and held by 1 WorldCat member library worldwide

The work presented in this thesis relates the development of a dual frequency comb spectrometer based on the electro-optic modulation of a continuous wave laser, and its utilisation for spectroscopic applications in the near- and mid-infrared.Since their discovery in the 1960s, frequency combs have revolutionised the physics, especially in metrology but also in spectroscopy, which lead to the Nobel Prize in Physics in 2005. In this domain of applications, dual frequency comb spectrometers are known to be complex to develop and use. A possibility to bypass these constraints is to build the spectrometer with electro-optic modulators. This particular architecture makes the experimental setup easy to use, thanks to the all-fibered feature and the lack of enslavement needed.In this manuscript, the work related describe first the architecture of a dual-comb spectrometer based on electro-optic modulators. We will see the advantages and disadvantages of the technique, especially for spectroscopic applications. We will also see the benefits of nonlinear phenomena in optical fibers to improve the experimental setup. Then, we show how the spectral range of the spectrometer can be extended around 2~µm, either by direct electro-optic modulation, or by frequency conversion in specific optical fibers.Finally, we will see the possibility to reach the mid-infrared by using nonlinear crystals. This last spectral extension will allow us to probe a spectral region highly suitable for spectroscopy, and hence to realise specific applications such as exhaled breath analysis
Widely tunable and SI-traceable frequency-comb-stabilised mid-infrared quantum cascade laser : application to high precision spectroscopic measurements of polyatomic molecules by Dang Bao An Tran( )

1 edition published in 2019 in English and held by 1 WorldCat member library worldwide

The thesis consists in developing a high-resolution mid-infrared spectrometer traceable to primary frequency standards and providing a unique combination of resolution, tunability, detection sensitivity and frequency control. A quantum cascade laser (QCL) emitting at 10.3 µm is phase locked to an optical frequency comb stabilized to a remote 1.55 µm ultra-stable reference developed at LNE-SYRTE, monitored against primary frequency standards and transferred to LPL via an active noise compensated fibre link. This results in a 0.1 Hz QCL linewidth, a stability below 10⁻¹⁵ at 1 s and an uncertainty on its absolute frequency below 4 × 10⁻¹⁴. Moreover, the setup allows the QCL to be widely scanned over 1.4 GHz while maintaining the highest stabilities and precision. This QCL was used to carry out saturated absorption spectroscopy of several molecules in a compact multipass cell. We demonstrated statistical uncertaintyon line-center frequencies at the kHz level and sub-10 kHz systematic uncertainty. We have recorded several singular K-doublets and many rovibrational transitions of methanol, in particular weak transitions and weak doublets - unreported so far. Precise parameters modelling trioxaneh ave been determined with only a few tens of rovibrational transitions recorded at unprecedented accuracy. The quadrupole hyperfine structure of an ammonia transition has been resolved for thefirst time. This setup constitutes a key element for the project aiming at the first observation of parity violation in molecules currently held at LPL, and, more generally, for various fields of physics, from atmospheric and interstellar physics to fundamental physics beyond the standard model
Spectroscopie à haute résolution de H2+ : production et refroidissement sympathique d'ions piégés. by Thomas Louvradoux( )

1 edition published in 2019 in French and held by 1 WorldCat member library worldwide

The objective of the project is to perform high-resolution Doppler-free two-photon vibrational spectroscopy on the H2+ molecular ions in order to obtain a direct optical measurement of the electron to proton mass ratio. The H2+ ions must be trapped and cooled but can only be cooled by sympathetic cooling using Be+ laser cooled ions. After a general introduction, the second part of this manuscrit describes ion trapping and presents the linear trap we use to trap H2+ and Be+ ions, as well as the methods used to create Be+ ions either by electronic impact or by photo-ionization of a stream of Be atoms. In the third part we present the state selective H2+ ion source using resonance enhanced multiphoton ionisation (REMPI) with a 303 nm pulsed laser, then we present the state-selected cold molecular ions obtained. In the fourth part we present a model for the resonance enhanced multiphoton dissociation spectroscopy technique that we use in order to detect the transition in H2+. In the fifth part we present the design and realization of the 313 nm laser source for Doppler cooling of Be+ ions. The sixth part presents the observation of Coulomb crystals of Be+ as well as mixed crystals of Be+ and H2+, it also presents the different experimental techniques that allow us to obtain and observe these crystals. The seventh part describes the spectroscopy source at 9,17 µm
Métrologie de la fréquence de transition 1S-3S dans l'hydrogène : contribution au débat sur le rayon de charge du proton by Hélène Fleurbaey( )

1 edition published in 2017 in English and held by 1 WorldCat member library worldwide

The precise measurement of the 1S-3S transition frequency of hydrogen could have a great impact on the proton charge radius puzzle, which results from the recent spectroscopy of muonic hydrogen. In our experiment, the two-photon 1S-3S transition is excited in a hydrogen atomic beam, with a continuous-wave 205-nm laser which is obtained by sum frequency generation in a non-linear crystal. The transition frequency is measured with respect to the LNE-SYRTE Cs clock by means of a frequency comb. Recording the signal for several values of an applied magnetic field allows to estimate the velocity distribution of the atoms in the beam and deduce the second-order Doppler shift. Other frequency-shifting systematic effects have been taken into account: cross-damping, light shift, collisions. A complete study has shown that the velocity distribution does not depend significantly on the pressure, and allowed to determine the collisional shift. Eventually, a value of the 1S-3S transition frequency is obtained with an uncertainty of about 5 kHz, or a relative uncertainty of 1.7 10^-12. It is in very good agreement with the CODATA recommended value. This new measurement contributes to the ongoing search to solve the proton radius puzzle
Liens ultra-stables par fibres optiques : déploiement vers plusieurs utilisateurs distants, étude des limites fondamentales et technologiques et nouvelles applications by Anthony Bercy( )

1 edition published in 2015 in French and held by 1 WorldCat member library worldwide

Les liens optiques permettent de disséminer une fréquence de référence ultra-stable à de nombreux laboratoires de recherche pour des mesures de très haute précision en métrologie et au-delà. Nous avons démontré premièrement une extraction simple d'un signal ultra-stable en différents points d'une liaison optique urbaine de 92 km, avec une stabilité de fréquence relative à 1 s de 1, 3 × 10-15 et sensiblement dégradée sur le long terme par les effets thermiques diurnes. Nous avons développé et testé un deuxième dispositif amélioré avec un montage interférométrique compact et activement thermalisé et une diode laser permettant de disséminer le signal vers un lien secondaire dont le bruit est activement compensé. Ces deux dispositifs permettront de disséminer le signal à de multiples utilisateurs en région parisienne et sur le réseau REFIMEVE+. Nous avons deuxièmement évalué les performances d'une méthode de type Two-Way pour la comparaison de deux références de fréquence par fibre optique. Nous avons testé la sensibilité de cette comparaison sur une boucle fibrée de télécommunication de 100 km en propagation unidirectionnelle puis bidirectionnelle, avec une excellente stabilité de la fréquence grâce à une très bonne réjection du bruit de la fibre. Ces résultats ouvrent la voie à la réalisation d'un réseau métrologique à l'échelle nationale et internationale pour la dissémination des meilleures horloges optiques
Optique non-linéaire résonante dans les lasers à cascade quantique by Sarah Houver( )

1 edition published in 2017 in French and held by 1 WorldCat member library worldwide

Quantum cascade lasers (QCLs) are powerful terahertz (THz) and mid-infrared (MIR) sources. Their emission relies on intersubband transitions i.e. transitions between confined electronic states in the conduction band of these semiconductor nanostructure-based lasers.This PhD thesis presents a fundamental study of resonant nonlinear optics in QCLs. Nonlinear frequency mixing between a THz or MIR QCL photon and a near infrared (NIR) pump has been shown within the QCL cavity. Nonlinearities from the QCL active region, composed of a set of quantum wells, can be enhanced owing to a NIR excitation that is resonance with interband transitions, and with the QCL photon in resonance with intersubband transitions. These resonant excitations permit a strong exaltation of the nonlinear susceptibility, allowing an efficient interaction without considerations of phase matching. Previous studies, limited to cryogenic temperatures, have shown nonlinear frequency mixing between a GaAs based THz QCL and an 800 nm NIR beam.This thesis presents an original work highlighting that resonant nonlinear optics in QCLs can be extended to the MIR, and to telecom range pump excitations, at room temperature. Furthermore, previously limits related to absorption at resonant excitations have also been partially overcome, by proposing a geometry in reflection.As well as proving an in-depth understanding of interband and intersubband nonlinearities in QCLs, this work paves the way to potential applications such as all optical wavelength shifting for telecommunications, and the up-conversion of THz and MIR photons into thetechnologically mature NIR range
Pompage rovibrationnel optique des molécules de césium by Isam Manai( )

1 edition published in 2013 in French and held by 1 WorldCat member library worldwide

The focus of this thesis is the manipulation of the internal degrees of freedom of translationally cold cesium molecules produced by photoassociation of cold atoms. Molecules formed in several vibrational and rotational levels are transferred by an optical pumping mechanism in the absolute rovibronic ground level (v = J = 0) or, alternatively, into other selected rotational levels of the electronic ground state. The main idea of the process is to make the target level not accessible ("dark") to the optical excitation. The suppression of the optical frequencies necessary to make a chosen state dark is obtained by spectral shaping of the excitation laser used for the optical pumping. Molecules present in this state cannot absorb photons because the laser does not provide the necessary resonant frequencies. While a broadband laser is dedicated to cool the vibrational degrees of freedom, a second narrowband laser is used to cool the rotational one because the small rotational splitting of Cs2 levels requires a narrowband source. This method is very general indeed. Simulations, for the cesium case are in very good agreement with the experiment, show that it can be applied to many other molecules. Furthermore, it could pave the way to the optical manipulation of molecular beams, to direct laser cooling of molecules and beam collimation with possible lithography applications
 
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Alternative Names
Klein, Anne Amy-

Languages
French (23)

English (8)