Lead Chalcogenide Quantum Dot-Doped Glasses for Photonic Devices

Tunable absorption and photoluminescence (PL) of lead chalcogenide quantum dots (QDs) doped in glasses due to the quantum confinements effect have been actively investigated for application as saturable absorbers, laser sources, and fiber-optic amplifiers. Optical properties of QDs have been carefully monitored by controlling their sizes through heat treatment and rare-earth ion doping. Two- and three-dimensional precipitation of lead chalcogenide QDs were also realized using silver ion exchange and femtosecond laser irradiation in combination with thermal treatment. Prototypes of microstructured single-mode fibers and tapered fiber amplifiers containing QDs proved potentials of these materials for fiber-optic amplifiers application. Further research works on QD-doped solid core fibers, surface passivation of quantum dots and their application for the mid-infrared optical devices are necessary.