TEMPERATURE-VARIATION OF THE MN2-XMNXTE CRYSTALS( LUMINESCENCE SPECTRA IN CD1)

The luminescence spectra in cubic mixed crystals Cd1-xMnxTe (0.6 < x < 1) grown by MBE have been studied in an energy range of around 2 eV a s a function of temperature between 4.2 and 300 K. The observed lumine scence is related to intra-ion optical transitions between the 3d elec tronic levels of Mn2+ perturbed by a crystal field. The luminescence d isplays a non-monotonic temperature dependence with a minimum at about 50 K. The occurrence of the minimum depends on the Mn molar fraction only very weakly. The temperature variation of the luminescence transi tion results mainly from the effect of screening of the Coulomb repuls ion force between d electrons and from variation of the crystal field potential due to thermal lattice dilation and electron-phonon interact ion.