HOMOCLINIC CHAOS IN A LASER CONTAINING A SATURABLE ABSORBER

Checks of homoclinic chaos made with nonlinear analysis techniques have been performed on the signals coming from a CO2 laser containing CH3I as a saturable absorber. The one-dimensional return maps of the regimes appearing inside the alternating periodic chaotic sequence are typical of homoclinic chaos. Numerical simulations give results in good agreement with the experimental observations. In the case of a fast absorber, a homoclinic tangency to a cycle created in a subcritical Hopf bifurcation is seen to be responsible for the homoclinic behaviour observed in the model.