Route to chaos and competition between relaxation oscillations for a semiconductor laser with optical feedback

Abstract

We report the first experimental observation of the route to chaos for semiconductor lasers with weak optical feedback. For increasing feedback level, the laser undergoes a quasiperiodic route interrupted by frequency locking, which is also predicted by a comprehensive numerical analysis. Experiments further demonstrate the occurrence of quantum-noise-induced transitions between two attractors with different relaxation oscillation frequencies. The attractors are created by two subsequent Hopf bifurcations of the same external cavity mode.