Optically injected single-mode quantum dot lasers

The response of an optically injected quantum dot semiconductor laser is studied both experimentally and theoretically. Specifically, the locking boundaries are investigated, revealing features more commonly associated with Class A lasers rather than conventional Class B semiconductor lasers (SLs). Further, various dynamical regimes are observed including excitability and multistability. Of particular interest is the observation of a phase-locked bistability. We determine the stability diagram analytically using appropriate rate equations for quantum dot lasers. In particular, the saddle-node (SN) and Hopf bifurcations forming the locking boundaries are examined and are shown to reproduce the observed experimental stability features. The generation of the phase-locked bistability is also explained via a combination of these bifurcations.