Dynamics of lasers with ultra-short optical feedback

The dynamical behavior of a single-mode laser subject to optical feedback is investigated in the limit, when the delay time is much shorter than the period of the relaxation oscillations. Use of an integrated DFB device allows us to control the feedback phase. The system shows a very rich manifold of nonlinear phenomena. Among them are two kinds of Hopf bifurcations associated with regular self-pulsations of different frequencies as well as a fold and period doubling bifurcation.