Optical properties of novel PbS and PbSe quantum-dot-doped alumino-alkali-silicate glasses

Lead sulfide PbS and lead selenide PbSe quantum dots (QDs) were synthesized in novel alumino-alkali-silicate glass. The synthesis of the nanocrystals was stabilized by introduction of two alkaline components. The presence of crystalline phase was confirmed by X-ray diffraction analysis, transmission electron microscopy and optical spectroscopy. For PbS (PbSe) QD-doped glass, the position of the 1S–1S excitonic absorption peak can be managed in the spectral range of 1.5–2.1 μm (for PbS) or 1.8–2.2 μm (for PbSe) by appropriate heat‐treatment mode. The corresponding QD average diameter was found to be 5.8–9.7 nm (for PbS) and 7.5–9.5 nm (for PbSe). The influence of the secondary heat-treatment at the temperatures of 490–525 °C on the PbS QD growth in the glass matrix initially treated at 480 °C was studied in details. The photoluminescence of the PbS-QD-doped glass was observed, it was referred to the radiative recombination of the excitons from the 1S–1S state. The possibility to obtaining narrow 1S–1S absorption lines at the wavelengths longer than 2 μm is discussed.

► Alumino-alkali-silicate glasses doped with spherical nm-size PbS or PbSe crystals. ► The growth of quantum dots is stabilized by two alkaline components Na2O and K2O. ► Detailed study of heat‐treatment influence on the optical properties of glasses. ► Photoluminescence is related with radiative exciton recombination from 1S–1S state.