Continuous-wave distributed Bragg reflector quantum cascade lasers with fine single-mode tuning up to 102 °C at λ∼8.4μm

• Published in: Optics communications Vol. 528
• Main Authors: Guan, Yanjiao, Lu, Xiyu, Cheng, Fengmin, Liu, Junqi, Wang, Lijun, Zhuo, Ning, Zhang, Jinchuan, Zhai, Shenqiang, Liu, Shuman, Liu, Fengqi
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2023
• Subjects: Distributed Bragg reflector; Mid-infrared; Quantum cascade laser; Single mode emission; Mid-infrared; Single mode emission; Quantum cascade laser; Distributed Bragg reflector
• ISSN: 0030-4018; 1873-0310
• DOI: 10.1016/j.optcom.2022.128994

We have demonstrated an 8.4μm stable single-mode quantum cascade laser using a two-section distributed Bragg reflector design. Output power of 252 mW, a threshold current density of 1.04 kA/cm2, and a characteristic temperature of 206 K were achieved during continuous-wave operation at room temperature. Robust single-mode emissions with all side-mode suppression ratios exceeding 25 dB were obtained at injection currents ranging from 420 mA to 900 mA and heat-sink temperatures ranging from 10 °C to 102 °C. Benefiting from the physical isolation of the two sections and from being mounted epilayer-side down on patterned submounts, the tiny tuning coefficients of the device are −0.003014 cm−1mA−1 and −0.0762 cm−1K−1. This type of single-mode quantum cascade laser with fine tuning characteristics is required to perform accurate detection of trace gases. •Stable single-mode DBR in long-wave IR band (8–12 μm) is realized.•The fine tuning property with the tiny tuning coefficients is conducive to the resolution and detection of dense gas absorption lines.•The device can work above 100 ℃ under CW operation and has ideal current characteristics such as low threshold, large dynamic range, which are beneficial for practical applications.