Chaos in practically isolated microcavity lasers.

We report that essentially isolated microcavity lasers may interact in the most complicated manner and drive each other chaotic. As the optical isolation between these lasers reaches presently practically attainable limits, instead of approaching independent operation, the lasers exhibit mutually induced chaotic oscillations. The chaos arises from an intricate coupling of the nonlinearities associated with coupled optical resonators and those evolving from the population dynamics in the active region. The investigation is performed using a composite-cavity theory and a class-B description of the gain medium. Bifurcation analysis identifies the source of instabilities and determines their robustness.