Modal gain characteristics of a 2 μm InGaSb/AlGaAsSb passively mode-locked quantum well laser

• Main Authors: Li, Xiang, Wang, Hong, Qiao, Zhongliang, Guo, Xin, Ng, Geok Ing, Zhang, Yu, Niu, Zhichuan, Tong, Cunzhu, Liu, Chongyang
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2018
• Subjects: Laser; Quantum Wells
• Online Access: https://hdl.handle.net/10356/88353; http://hdl.handle.net/10220/44613
• Institution: Nanyang Technological University

Passive mode locking with a fundamental repetition rate at ∼18.46 GHz is demonstrated in a two-section InGaSb/AlGaAsSb quantum well laser emitting at 2 μm. Modal gain characteristics of the laser are investigated by performing the Hakki-Paoli method to gain better insight into the impact of the absorber bias voltage (Va) on the light output. The lasing action moves to longer wavelengths markedly with increasing negative Va. The light output contains more longitudinal modes in the mode locking regime if the gain bandwidth is larger at a certain Va. Our findings provide guidelines for output characteristics of the mode-locked laser.