  Luminescence spectroscopy experiments were realized for single colloidal
quantum dots CdSe/ZnS in a broad temperature range above room temperature in a
nitrogen atmosphere. Broadening and shifts of spectra due to the temperature
change as well as due to spectral diffusion processes were detected and
analyzed. A linear correlation between the positions of maxima and the squared
linewidths of the spectra was found. This dependence was explained by a model
which takes into account the slow variation of the electron-phonon coupling
strength.
