PbSe quantum dots grown in a high-index low-melting-temperature glass for infrared laser applications

PbSe quantum dots (QDs) were grown in high-refractive-index low-melting-temperature lead-phosphate glass. QDs with various sizes ranging from 2 nm to 5.3 nm were grown by controlling the growth parameters, heat-treatment temperature and time. The corresponding room-temperature exciton absorption was tuned within the infrared region from 0.93 µm to 2.75 µm. Photoluminescence was measured for samples with absorption peaks above 0.95eV. Real time quantum dot growth was demonstrated by monitoring the evolution of exciton absorption with temperature and time duration. As a demonstration of the use of QDs in laser applications, the saturation fluence (Fsat) of one of the QDs was evaluated and found to be ~2.1 µJ/cm2 at 1.2 µm.