Reflection sensitivity of dual-state quantum dot lasers
This work experimentally and theoretically demonstrates the effect of excited state lasing on the reflection sensitivity of dual-state quantum dot lasers, showing that the laser exhibits higher sensitivity to external optical feedback when reaching the excited state lasing threshold. This sensitivity can be degraded by increasing the excited-to-ground-state energy separation, which results in a high excited-to-ground-state threshold ratio. In addition, the occurrence of excited state lasing decreases the damping factor and increases the linewidth enhancement factor, which leads to a low critical feedback level. These findings illuminate a path to fabricate reflection-insensitive quantum dot lasers for isolator-free photonic integrated circuits.
Zhiyong Jin, Heming Huang, Yueguang Zhou, Shiyuan Zhao, Shihao Ding, Cheng Wang, Yong Yao, Xiaochuan Xu, Frédéric Grillot, Jianan Duan. Reflection sensitivity of dual-state quantum dot lasers[J]. Photonics Research, 2023, 11(10): 1713.