Optical Feedback Dynamics in Dual-state Quantum Dot Lasers

In this paper, the dynamics of dual-state quantum dot (QD) lasers under external optical feedback are investigated by solving the three-level rate equations in the time domain. The results show that the high excited-to-ground-state (ES-GS) energy separation in QD lasers leads to a high ES-GS threshold ratio hence strengthening the feedback resistance. These findings shed new light on the fabrication of feedback-resistant dual-state QD lasers for isolator-free photonic integrated circuits.