On the quantitative absorption and Stokes shift in PbSe quantum dots embedded in glasses

Abstract

The synthesis of PbSe quantum dots (QDs) in silicate glasses was achieved by a simple melt-annealing technique. Transmission electron microscopy analysis proves the formation of PbSe QDs in glasses. The absorption spectra show that the light absorption originates from the PbSe QDs in glasses mostly, and the energy-integrated molar extinction coefficient for the first exciton transition was deemed to be only about 1/10 of those from colloidal PbSe QDs. The photoluminescence analysis reveals that the Forster energy transfer is responsible for the shape of the PL peak. For the sample with PbSe QDs in a small radius of 5.2 nm, a pronounced Stokes shift of 70 meV was found, and the Huang–Rhys factor was calculated to be 2.1.