Temperature dependence of the absorption spectra in CdTe-doped glasses

Abstract

We present absorption spectra as a function of temperature for CdTe quantum dots in doped glasses. We calculate the absorption spectra considering the transition energies from a spherical model. We consider also the inhomogeneous broadening due to the quantum-dot size distribution and the homogeneous broadening, due mainly to electron-phonon interactions. The samples grown with a two-step heat treatment present very thin size distributions, with a standard deviation of 5.8%, which is comparable to the best CdSe samples in the literature. Also, the results show that the homogeneous width increases as the quantum-dot size decreases, indicating an enhancement of the electron-phonon interaction for small dots.