This thesis is a theoretical and experimental study of the dynamics of an edge-emitting laser diode (850 nm) with phase-conjugate feedback. The experimental device is designed to see the dynamical range of the laser through the temporal and spectral properties while the feedback rate varies. Phase-conjugate feedback is performed through four-wave mixing in a photorefractive crystal. The propagation time of the laser beam in the external cavity is termed external time delay. Under the effect of the feedback, the system shows a wide dynamical range including chaos and self-pulsing states which characteristic properties are determined by the length of the external cavity. For the first time self-pulsing states at frequencies multiples of the fundamental frequency of the external cavity are evidenced. Simulations carried out based on the commonly-used Lang-Kobayashi laser rate equations provide theoretical confirmations to the experimental observations. The main topics tackled here are chaos crisis and bistability of pulsing solutions, self-pulsing regimes (through their stabilization and destabilization) and the transitions between them, characterization of extreme events of two kinds along with their statistical distribution and delay-induced deterministic coherence resonance of low frequency fluctuations. Beyond the fundamental interest of these results and the many comparisons that can be made with other laser systems, applications in the field of all-optical signal generation and control of chaos are direct consequences of this study.

Cette thèse consiste en une étude théorique et expérimentale de la dynamique d'une diode laser à émission latérale (850 nm) avec rétroaction optique à conjugaison de phase. Le dispositif expérimental est conçu afin de voir la diversité dynamique du laser à travers l'analyse temporelle et spectrale alors que le taux de rétroaction varie. La rétroaction à conjugaison de phase est effectuée par mélange à quatre ondes dans un cristal photoréfractif. Le temps de propagation du faisceau laser dans la cavité externe est appelé retard. Sous l’effet de la rétroaction, le système montre une grande richesse dynamique qui varie du chaos total à des régimes auto-pulsés aux fréquences déterminés par le longueur de la cavité externe pour la première fois mis en évidence ici. Des simulations menées en parallèle basées sur les équations de Lang-Kobayashi couramment utilisées apportent des confirmations théoriques aux observations expérimentales. Les principaux points traités sont la crise chaotique et bistabilité de solutions pulsées, les régimes auto-pulsés (stabilisation et déstabilisation) ainsi que les transitions entre eux, la caractérisation d’événements extrêmes de différentes natures avec la distribution statistique associée ainsi qu’une résonance cohérente déterministe de fluctuations à basse fréquence induite par le retard. Au-delà de l’intérêt fondamental de ces résultats et des comparaisons qui peuvent être établies avec d’autres systèmes laser, des applications dans la génération de signaux tout-optique ainsi que le contrôle du chaos sont des débouchés potentiels de cette étude. / This thesis is a theoretical and experimental study of the dynamics of an edge-emitting laser diode (850 nm) with phase-conjugate feedback. The experimental device is designed to see the dynamical range of the laser through the temporal and spectral properties while the feedback rate varies. Phase-conjugate feedback is performed through four-wave mixing in a photorefractive crystal. The propagation time of the laser beam in the external cavity is termed external time delay. Under the effect of the feedback, the system shows a wide dynamical range including chaos and self-pulsing states which characteristic properties are determined by the length of the external cavity. For the first time self-pulsing states at frequencies multiples of the fundamental frequency of the external cavity are evidenced. Simulations carried out based on the commonly-used Lang-Kobayashi laser rate equations provide theoretical confirmations to the experimental observations. The main topics tackled here are chaos crisis and bistability of pulsing solutions, self-pulsing regimes (through their stabilization and destabilization) and the transitions between them, characterization of extreme events of two kinds along with their statistical distribution and delay-induced deterministic coherence resonance of low frequency fluctuations. Beyond the fundamental interest of these results and the many comparisons that can be made with other laser systems, applications in the field of all-optical signal generation and control of chaos are direct consequences of this study.