Dual state antiphase excitability in optically injected quantum dot lasers

Depending on device and operating parameters, the emission of lasers based on InAs quantum dot (QD) material may come from the ground state (GS) only, from the first excited state (ES) only or simultaneously from both states. When the emission is from the ES only, optical injection at the GS frequency can completely suppress the ES output and instead, phase-locked emission from the GS can be obtained. We report on a variety of non-linear phenomena obtained when the frequency of the master laser is varied revealing two antiphase, dual-state excitable regimes.