Lithium niobate(LiNbO3) has been widely used in optical frequency converter, electro-optical modulator, surface acoustic waveguide filter, and photorefractive recording due to its ease of growth, high nonlinear coefficient, and excellent optical quality. In this thesis, we report the use of laser-heated-pedestal growth technique on LiNbO3 crystal fibers with in-situ electric field. In the process of the wavelength conversion, based on the cascaded second-order nonlinearity, we designed a 1.55-mm-band wavelength converter in optical communication, which has spectral widths for the pumping source and the output signal of 0.78nm and 80nm, respectively. In the experiment, we had grown a-axis single domain LiNbO3 crystal fiber. We also studied the dynamics of poling mechanism for various electric field. We applied 1kV/mm electric field near the Curie temperature on the LiNbO3 with the diameter up to 190mm and got a periodic domain structure of 18.9mm. The techniques are expected to be useful for in high-efficient nonlinear optical applications.

Lithium niobate is a high performance nonlinear optical material that has found wide-spread applications in electro-optical modulation and nonlinear optics. In this study, periodically poled lithium niobate crystal fibers are characterized with SH microscopy. The natural optical sectioning enabled by SH allows rapid and non-destructive mapping of the crystal fiber¡¦s detailed features in 3D (1024x1024 pixel image about 40 minutes). We utilize simulate and Fourier transform to analyze the SHG images, besides observing the variation of SHG efficiency after annealing.

A sub-nanosecond green laser source has big demand in such fields like spectroscopy, micromachining, fluorescence imaging, and laser displays. Most often green light is produced by frequency doubling of pulsed laser sources based on Nd3+-ion or Yb3+-ion doped gain media that oscillate in the near-IR range. For creating compact and relatively small source of green light suitable for broad type of applications a passively Q-switched Nd:YAG microchip laser (Teem Photonics) operating at 1064 nm with 6.9 kHz repetition rate was chosen. It delivers 560 ps long pulses with 10 μJ energy, corresponding to an average output power of 69 mW. Crystals of BiBO, KTP, LBO, and PPLN were chosen for frequency doubling. Main goal of this work was to study the characteristics of these crystals under similar experimental conditions and to select the most efficient one for this task. To optimize second harmonic generation (SHG) process, different focusing conditions were used during the experiments. In this work we measured the second harmonic output power as a function of the incident power, beam profile for fundamental and second harmonic radiation for all crystals, and second harmonic output power as a function of temperature for PPLN crystal. Crystal of PPLN was found to be the most suitable for SHG process and produced it with up to 60% conversion efficiency.

A sub-nanosecond green laser source has big demand in such fields like spectroscopy, micromachining, fluorescence imaging, and laser displays. Most often green light is produced by frequency doubling of pulsed laser sources based on Nd3+-ion or Yb3+-ion doped gain media that oscillate in the near-IR range. For creating compact and relatively small source of green light suitable for broad type of applications a passively Q-switched Nd:YAG microchip laser (Teem Photonics) operating at 1064 nm with 6.9 kHz repetition rate was chosen. It delivers 560 ps long pulses with 10 μJ energy, corresponding to an average output power of 69 mW. Crystals of BiBO, KTP, LBO, and PPLN were chosen for frequency doubling. Main goal of this work was to study the characteristics of these crystals under similar experimental conditions and to select the most efficient one for this task. To optimize second harmonic generation (SHG) process, different focusing conditions were used during the experiments. In this work we measured the second harmonic output power as a function of the incident power, beam profile for fundamental and second harmonic radiation for all crystals, and second harmonic output power as a function of temperature for PPLN crystal. Crystal of PPLN was found to be the most suitable for SHG process and produced it with up to 60% conversion efficiency.

Due to its easy growth, higher nonlinear coefficients, and better optical characteristics, LiNbO3 is broadly used as nonlinear crystal in laser system and wavelength converter in optical communication systems. In this thesis, we discuss the use of LHPG method to grow periodically poled LiNbO3 crystal fiber without metallic patterns. During the growth, micro-swing is managed to assist poling process, simultaneously we can understand and simulate the electric-field induced current. Using the relation between current waveform and micro-swing amplitude, we can quantify the micro-swing amplitude, and establish feedback control to enhance the stability during crystal fiber growth process. The achieved internal SHG conversion efficiency is 14.8 % with a quasi-phase matched period of 15.45 £gm. Besides promoting process stability and improving uniformity of domain inversion period, it is our hope that the relation between domain inversion and measured induced current can be clarified in the future. Due to the low Curie temperature of LiTaO3, it is expected that our experience on LiNbO3 can facilitate the development of periodic poling on LiTaO3.

All-optical wavelength conversion is necessary for efficient managing and routing optical signals in a complex all-optical network model. With the bit-rate increases as time evolves, all-optical conversion will become more promising due to its high transparency for data rate and format and the low cost penalty compared with O/E/O method. Periodically poled LiNbO3 crystal fiber (PPLNCF) for wavelength conversion is successfully grown by LHPG method with in situ electric field bias. The pitch depends on the frequency of applied external electric field. Domain period of 9.76 microms and crystal length over 160 mm are demonstrated in this thesis. Electrically induced micro-swing during growth is managed to assist poling process. After the optical test, 0.27% peak offset shows the accuracy of our fabrication. The wavelength and temperature bandwidths were measured to be 17.2 nm and 42.8oC. With the improvement of uniformity, broadband design, and the implementation of guiding structure, high quality PPLNCF will be widely promoted for its superior performance.

Lithium niobate (LiNbO3) and Lithium tantalate (LiTaO3) are high-performance nonlinear optical materials that have been popularly used in electro-optical modulation and nonlinear optics. Second-harmonic generation (SHG) microscope is applied to get SH images, as compared to etching method. SH image method has the advantage of faster and non-invasive inspection. Our system can rapid and non-destructive mapping of the detailed features of the crystal fibers in three dimensions. By simulation, we can explain that in the interface of +Z and ¡VZ domain, because the Li ions can stay in positive and negative two stable energy valleys. It may induce stronger SH intensity by QPM than +Z and -Z domain.

Depuis une quinzaine d'années, la mise en ?uvre par commutation électrique de structures ferroélectriques périodiquement polarisées (PP), à température ambiante, occupe une place importante parmi les techniques de fabrication de dispositifs pour la génération de la seconde harmonique et l'oscillation paramétrique optique. Il s'agit de mettre en ?uvre les effets non- linéaires (NL) qui apparaissent dans les cristaux ferroélectriques. Parmi ces différents matériaux, c'est le niobate de lithium LiNbO3 (LN) qui est le plus utilisé. Dans un premier temps, les efforts de recherche se sont concentrés sur la fabrication de ces structures et la mise au point de dispositifs de conversion. Ce n'est que récemment que des études ont été consacrées, plus spécifiquement, à la caractérisation de ces structures en domaines. Dans ce travail nous montrons comment la microsonde Raman peut être utilisée pour la caractérisation des microstructures de domaines ferroélectriques antiparallèles dans du niobate de lithium périodiquement polarisé (PPLN). L'intensité Raman de modes transverses et longitudinaux de phonons optiques a été enregistrée à travers les murs séparant les domaines ferroélectriques, à la fois, en surface et en volume. Les diverses contributions à la polarisabilité et à l'intensité diffusée Raman, linéaire et non linéaire, sont analysées afin de comprendre les variations du spectre Raman observées dans les différentes configurations et géométries des échantillons. Le changement des intensités intégrées à travers ces structures de domaines est attribué à l'influence des contraintes mécaniques et à un champ de charges d'espace surfacique.

Le but de cette thèse est de développer des sources d’intrication photonique en vue d'applications en sciences information quantique. Dans ce contexte, nous présentons une source très performante et entièrement guidée permettant, au moyen d'une boucle de Sagnac, la génération d'états hyper-intriqués en polarisation et en énergie-temps. La configuration guidée rend le dispositif versatile, efficace et compatible avec une large bande spectrale, répondant ainsi au besoin des systèmes et réseaux de communication fibrés. À cette fin, nous avons distribué simultanément dans différents canaux télécoms des paires de photons hyper-intriqués au moyen de multiplexeurs en longueur d'onde à 5 canaux (DWDM), augmentant de fait le débit. La qualité de l'intrication est validée par la violation d'une inégalité de Bell étendue à un espace de Hilbert à 16 dimensions. Afin de pouvoir interfacer des photons aux longueurs d'ondes des télécommunications avec les bandes d'absorption des mémoires quantiques situées dans le visible, nous avons également développé une interface cohérente en longueur d'ondes. Un nouveau dispositif de métrologie quantique permettant la mesure avec une précision inégalée des effets de la dispersion chromatique dans les fibres optiques standards est également proposé. Notre approche "quantique" améliore la précision par un facteur 2.6 par rapport aux méthodes de mesures conventionnelles. Dans ce même contexte, nous avons aussi implémenté un nouveau protocole de métrologie de la phase de deux photons en ne détectant uniquement qu'un seul photon. Cette réalisation ouvre la voie à des applications potentielles simples s'appuyant sur peu de ressources au niveau de la détection. Finalement, dans la perspective de la miniaturisation de dispositifs quantiques, nous avons démontré un générateur d'intrication annoncée intégré sur puce qui trouve des applications en calcul et métrologie quantique. / The aim of this thesis was to develop photonic entanglement sources and study their implementation in the general field of quantum information technologies. To this end, a novel fully wave-guided, high performance photonic entanglement source is presented, able to generate hyper-entangled states in the observables of polarization and energy-time by means of a nonlinear Sagnac loop. The waveguide-based design makes it flexible, reliable, and adaptable to a wide spectral range, paving the way towards compact photonic entanglement generators, compatible with fiber-based communication systems and networks. This has been underlined by generating and distributing hyperentanglement in 5x2 dense wavelength division multiplexed channel telecom pairs, simultaneously, towards higher bit rates. The quality of the generated entanglement has been qualified by violating the Bell inequalities in a 16-dimension Hilbert space. Moreover, to adapt the wavelength of the entangled telecom photon pairs to the absorption wavelength of current quantum memory systems, a coherent wavelength converter is demonstrated. Furthermore, within the framework of quantum metrology, a new concept for a high-precision chromatic dispersion (CD) measurement in standard single mode fibers is introduced and demonstrated. In this demonstration, due to conceptual advantages enabled by quantum optics, an unprecedented 2.6 times higher accuracy on CD measurements is shown, compared to state-of-the-art techniques. In the same context, a new protocol for measuring two-photon phase shifts is performed using single photon detection only, promising scalable and potential real device applications with limited resources and simplified detection schemes. Finally, any potential application of quantum optics will be realized using small-scale devices. In this framework, an integrated on-chip heralded path entanglement generator is demonstrated, and shown to be adaptable to logic gate operations.

Cette thèse en deux parties porte sur le développement de sources lasers nano et picosecondes et leurs applications. La première partie présente l'étude, et la réalisation d'une chaîne amplificatrice laser nanoseconde pour l'allumage de turbomoteurs. Après avoir présenté les performances et l'évolution de cette chaîne seront présentes les résultats des campagnes d'essais réalisées sur une chambre de combustion sur un banc d'essai à l'ONERA dans des conditions de basses températures et de basses pressions. La deuxième partie de cette thèse traite du développement d'un oscillateur paramétrique optique (OPO) nécessaire pour accorder en longueur d'onde dans l'infrarouge un laser impulsionnel picoseconde ou femtoseconde à haute cadence et forte puissance moyenne. Après avoir présenté la cavité de l'OPO ainsi que ses performances, nous détaillerons la capacité de cet OPO à générer des impulsions femtoseconde comprimées à partir d'impulsions pompe présentant un étirement temporel. / This two-part thesis focuses on the development of nano and picosecond laser sources and their applications. The first part presents the study, and the realization of a nanosecond laser amplifier chain for the ignition of turboshaft engines. After the repport of the performances and the evolution of this amplifier chain will be presented the results of the tests carried out on a combustion chamber on a test bench at ONERA under low temperatures and low pressures conditions. The second part of this thesis deals with the development of an optical parametric oscillator (OPO) in order to tune in the infrared the wavelength of a pulsed picosecond or femtosecond laser at high cadency and high average power. After presenting the OPO cavity and its performance, we will detail the ability of this OPO to generate compressed femtosecond pulses from pump chirped pulses.