Bistabilité, multistabilité et chaos en longueur d’onde

Unstable and chaotic phenomena have lead to a number of studies in the area of optics which allows easy experimental verifications owing to the use of optical sources and feedback, and optically-induced non linearities. Most of those studies have dealt with hybrid or all-optical systems working in monochromatic light and whose dynamic variable of concern was the energy. The work presented here deals with chaotic phenomena linked to the wavelength variable. The latter opens up new possibilities inherent to the high flexibility in inducing wavelength non linearities and their control, and to the greater dynamic excursion of the signals. Wavelength bistable and multistable devices are presented, together with a discussion of the various routes to chaos they can generate. The prospects given in the conclusion deal with the use of the wavelength variable in a chaos generator, the multivalued coding in wavelength of signals, and the chaos that would be generated by a system with a feedback featuring a signal-dependent optical delay.