Infrared Colloidal Quantum Dot Lasers

Abstract Infrared (IR) lasers are crucial for diverse applications including optical communications, environmental sensing, biomedical imaging, ranging, and process quality control. Conventional IR lasers, based on III‐V semiconductor materials or optical fiber systems, face significant challenges such as high fabrication costs, limited wavelength tunability, and incompatibility with silicon photonics. Colloidal quantum dot (CQD) IR lasers have emerged as a promising alternative, offering solution‐processibility, size‐tunable emission wavelength, and low‐cost fabrication. Recent efforts have enabled the realization of room‐temperature IR lasers operating in the telecommunication band and even expanding their emission into the extended short‐wave infrared (e‐SWIR) range. While advancements in CQD synthesis, surface passivation, and wavefunction engineering have improved lasing performance by suppressing Auger recombination, leveraging advanced mechanisms such as doping strategies and cascade charge transfer, and increasing the absorption crosssection. Most demonstrations still rely on intense pulsed excitation to achieve stimulated emission within a short optical gain lifetime. Moreover, substantial challenges remain in realizing continuous‐wave operation, and electrically‐driven lasers. This minireview highlights recent breakthroughs in CQD IR lasers, compares them with their visible counterparts, and explores future directions to address existing challenges, paving the way for next‐generation silicon photonic integration.