Chaotic dynamics of a laser with feedback

A diode-pumped solid-state laser is constructed. The complex dynamics resulting from electronic feedback of the laser intensity are explored and characterized. The laser is further perturbed by periodic, quasiperiodic, and chaotic drives.; Distinct stable and chaotic regimes can be elicited from the laser by tuning the bias of the feedback loop. An additional branch of the feedback loop, containing a derivative filter, provides access to new kinds of dynamics, including a more gradual transition to chaos. The whole feedback network together allows the laser dynamics to be selected from among a wide range of chaotic waveforms distinguished by statistical or spectral information. In other words, this laser system can be used as a tunable generator of chaotic functions.; The laser with feedback is perturbed by a signal composed of one or two sinusoids. The phase of the chaotic intensity signal is constructed using the complex analytic signal. With one-frequency driving, the laser dynamics show phase entrainment for sufficient driving amplitude. Competition between two distinct driving frequencies to phase synchronize the intensity dynamics of a chaotic laser is observed in the case of two-frequency driving. Competing frequencies alternately show phase-locking and phase-slipping. Competition is quantified by calculating the portion of time the laser phase-locks to each of the driving frequencies and their average.; The electronic feedback signal driving the chaotic dynamics of a laser is recorded. Feedback is removed and the recorded signal is replayed to the laser. Instead of repeating the original dynamics, the laser displays generalized synchronization to its previous waveform. Generalized synchronization error is minimized for slightly mismatched laser parameters. In addition, the generalized synchronization includes phase synchronization between drive and response with synchronized phase slips.; A physical mechanism for generalized synchronization relying on hidden variables of the laser is proposed. A model including this mechanism is investigated and shows good agreement with the experiment.