Relative intensity noise reduction in a dual-state quantum-dot laser by optical feedback

We report a reduction of the relative intensity noise (RIN) in a dual-state emitting quantum-dot laser subject to the state-selective optical feedback on the ground state and excited state. Numerically, we map the evolution of the RIN for variations of the optical feedback phases for both states. We report important differences in the impact of the feedback when applied to the ground or excited state, and observe regimes for which a significant reduction in RIN is achieved. Experimentally, we confirm these results and achieve a 16 dB reduction of the RIN via a careful and independent tuning of the optical feedback phase for each state.