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 mu m (for PbS) or 1.8-2.2 mu m (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 degrees C on the PbS QD growth in the glass matrix initially treated at 480 degrees 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 mu m is discussed. (C) 2012 Elsevier B.V. All rights reserved.