La tenue au flux des traitements de surfaces optiques constitue aujourd'hui un enjeu majeur pour le développement des lasers de puissance à courtes durées d'impulsion. L’étude des interactions laser-matière en régime sub-picoseconde a montré que l’initiation de l'endommagement laser est le résultat de processus d’excitation fortement non-linéaires (photoionisation, ionisation par impact et avalanche électronique). Dans cette thèse, un dispositif de tests multiparamétriques a été développé pour l’étude de la tenue au flux des composants optiques. Différentes études expérimentales ont été menées sur des matériaux diélectriques, en couche mince ou en matériau massif, afin d’apporter des données nouvelles sur les matériaux couches minces assez peu étudiés dans la littérature. L’étude de l’influence de la longueur d’onde a révélé différentes phases de prédominance des processus d’ionisation. L’influence du nombre de tirs à différentes longueurs d’ondes aussi a été étudiée, en considérant différentes techniques de dépôt de couches minces. L’interprétation de ces résultats expérimentaux est soutenue par un modèle de simulation numérique que nous présentons en détail dans le manuscrit. Une place, non moins importante, a été accordée dans notre travail à la métrologie de l’endommagement. Nous avons proposé et appliqué l’utilisation d’un dispositif original de mesure quantitative de phase pour l’analyse des processus d’endommagement. Et pour terminer nous avons développé un système de microscopie pompe-sonde afin de pousser les investigations sur les processus en jeu lors de l’interaction laser-matière en régime sub-picoseconde. / Laser fluence resistance of optical surfaces is a major challenge for the development of high power and short duration pulse lasers. Studies on laser matter interactions show that the damage initiation is the result of highly nonlinear excitation process such as photoionization, impact ionization and electronic avalanche. In this PhD thesis we focused on the study of the damage and the response of materials after this initiation and their dependence with laser parameters, this in order to better understand the complex mechanisms of damage, identify laws of relevant scales for applications, and enable new optical design with higher laser resistance and lifetimes. A multi parametric experimental testing setup was developed for studying laser resistance of optical components. To collect new data on thin film materials damage dependences, which have been less studied in the literature, different experimental studies have been conducted on dielectrics, in coating or bulk form. The study of the dependency of damage with laser wavelength reveals different ranges characterized by the electronic processes occurring during the interaction. We have considered also the effect of multiple pulse irradiations, with different wavelengths and on coatings realized by different technologies. All these experimental results have been discussed with the help of a numerical simulation model we have developed and presented in this thesis. We have also proposed an original method based on optical phase difference measurement for damage characterization and study. We finished with some experiments on the time resolved microscopy measurements and investigations of damage processes.

The Complementary Metal-Oxide-Semiconductor (CMOS) industry has seen tremendous developments over the past several decades and state-of-the-art fabrication technology has likewise been developed. This fabrication technology develops Photonic Integrate Circuits (PIC) which can guide, split, and modulate photonic waves within a small chip scale. On-chip optical phased arrayed waveguides that operate at high power overcome the current limitations of some conventional applications. This paper discusses two applications of on-chip optical waveguide systems: optical phased array (OPA)-based Light Detection and Range (LiDAR) and waveguide array Dielectric Laser Accelerator (DLA). Both the LiDAR and DLA structures require similar properties to achieve optimized performance. These properties are as follows: capability to handle high power, the ability to split the high power evenly through several waveguide branches and distribute the same degree of optical phase on each branch at specific spatial locations, efficient designs of active phase-tuning structures, and the ability to re-combine several waveguide branches into the sub-wavelength pitch spacing array without crosstalk. Additionally, both structures must resolve specific fabrication challenges on each waveguide component. To address these issues, this paper discusses the theoretical reviews of OPA, the Laser-Induced Damage Threshold (LIDT) of optical waveguide materials, and techniques to reduce crosstalk in sub-wavelength pitch size arrays, such as extreme skin-depth (e-skid) waveguides and propagation constant mismatched waveguides. We propose optimized designs for both OPA-based LiDAR and waveguide array DLA with passive and active devices, respectively, and explain the optimized parameters and its simulation results for each component from the full layout of devices. Furthermore, we discuss the fabrication process of the devices and show the resolutions of fabrication challenges, such as trapping void gaps in an e-skid array structure, writing errors of electron beam lithography of large dense patterns, and silicon nitride to silicon hybrid waveguide pattern alignments. Next, we show the experimental setups and the measurement results from the fabricated OPA devices and analyze the results. Finally, this paper concludes the research of the proposed devices and proposes more designs for both OPA-based LiDAR and waveguide arrayed DLA structures that can further increase increase its performance.<br>

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