SWIR high-power narrow-linewidth semiconductor lasers for LiDAR and communications

Shortwave infrared (SWIR), particularly the 1.5-μm waveband, exhibits the lowest signal loss and dispersion in optical fibers, making it suitable for long-distance, wide-bandwidth, high-speed data transmission. Meanwhile, 1.5-μm lasers have advantages such as good eye safety, strong atmospheric penetration, high signal-to-noise ratio, and strong anti-interference capabilities, making them very suitable for long-distance LiDAR applications. High-power, narrow-linewidth SWIR semiconductor lasers have significant advantages and broad application prospects in LiDAR, data centers, and coherent optical communications due to their small size, light weight, high efficiency, easily controllable power and wavelength, and rapid modulation characteristics. To meet the application demands of LiDAR, data centers, and coherent optical communications, we have developed various high-power, narrow-linewidth SWIR semiconductor lasers in the 1.2~1.7-μm band using InP-based AlGaInAs multiple quantum well materials and ridge waveguide structures. These include DFB lasers, DFB and SOA integrated MOPA lasers, and external cavity lasers (ECL). By adopting different epitaxial and resonator structures, we have achieved narrow linewidths (25~200 kHz for DFB, <10 kHz for ECL), high-power output (tens of mW to hundreds of mW), short pulses (a few ns to hundreds of ns), precise control of the mode field, as well as collimated output and fiber-coupled output. These lasers are widely used in optical communications, silicon photonics, LiDAR, and fiber-optic sensing, etc. In this work, we provide a detailed description of chip design, device packaging, temperature control, targeting diverse applications in the fields of coherent LiDAR and optical communications.