Periodic orbits and synchronous chaos in lasers unidirectionally coupled via saturable absorbers

We study a model for two unidirectionally coupled molecular lasers with a saturable absorber. Our numerical bifurcation study shows the existence of isolas of in-phase periodic solutions as physical parameters change. There are also other non-isola in-phase and intermediate-phase families of periodic oscillations. The coupling parameter strongly affects the stability of these periodic solutions. In this model the unstable periodic orbits belonging to the in-phase isolas constitute a skeleton of the attractor, when chaotic synchronization sets in for a set of physically relevant control parameters