Broadband near-infrared luminescence and tunable optical amplification around 1.55 μm and 1.33 μm of PbS quantum dots in glasses

Silicate glasses containing PbS quantum dots (QDs) with narrow size distribution were prepared through heat treatment. Transmission electron microscopy (TEM) results show that spherical PbS QDs are densely dispersed in the glassy matrix. Using ZnS–PbO to replace PbS as precursor of PbS QDs, the size distribution of PbS QDs in glasses becomes more uniform. Tunable infrared luminescence from 1100 to 2200 nm has been obtained by controlling the glassy matrix and preparation parameters. Obvious optical amplification at communication windows of 1.55 μm and 1.33 μm is probed, and the PbS QDs doped glasses using ZnS–PbO as precursor exhibit larger optical amplification. The PbS QDs doped glasses with intense optical amplification are considered to be promising candidate as gain medium for broadband fiber amplifier and tunable fiber laser.

► Optical amplification of PbS QDs in glasses at 1.55 μm is characterized for the first time. ► Using ZnS–PbO to replace PbS as precursor of PbS QDs, the size distribution of PbS QDs in glasses becomes more uniform and narrower. ► Using ZnS–PbO to replace PbS as precursor of PbS QDs, optical amplification is remarkably improved, and the possible enhancing mechanism is also discussed.