Statistical studies of semiconductor lasers with delayed optical feedback

We investigate the statistics of the irregular fast pulsing intensity dynamics of semiconductor lasers with delayed optical feedback operating in the low-frequency fluctuation and coherence collapse regimes. We demonstrate experimentally that the probability density distributions of the laser intensity on a picosecond timescale do not depend on the number of optical modes involved in the laser emission, using two complementary high-resolution experimental measurement systems: a high-bandwidth sampling digitizer and a single shot streak camera. The experimental. results are in agreement with numerical results based on the Lang-Kobayashi equations.