Statistical properties of the dynamics of semiconductor lasers with optical feedback

We measure the time-resolved probability distribution of the light emitted by a semiconductor laser with optical feedback. We show and analyse, for the first time, high-frequency fluctuations of the laser intensity in the coherence collapse regime. Our results suggest that the noise induces the power drop-outs and the laser recovers in a deterministic fashion. We also give a new mechanism for a transition between erratic and synchronised behaviour in the laser dynamics.