Energy spectrum of quantum wells in PbTe/PbEuTe-based structures from photoluminescence data

It is shown that the energies of radiative transitions between the ground states of electrons and holes for high-quality deep PbTe quantum wells at low temperatures are described well within the framework of the two-band model with regard to the nonparabolicity, strong anisotropy, and multivalley character of the band structure and also uniaxial deformation, that is present in the heterostructure. For a two-dimensional system, the temperature coefficient of the variation of the forbidden band gap decreases with decreasing well width, which is explained by a weakening of the electron-phonon interaction.