The temperature dependence of the interband transition in an α-V2O5 film was investigated using absorption and photoluminescence spectral measurements at a temperature range of 10–300 K. Transmission measurements in the experimental temperature range indicate that the α-V2O5 film has two distinct interband transitions, implying indirect and direct transitions. This result was confirmed by spectroscopic ellipsometry. The blue shift of both the transitions in the α-V2O5 film with decreasing temperature was explained by a reduction in the lattice-dilatation effect and the electron-phonon interaction. The PL measurements in the experimental temperature range showed that the emission near 530 nm is due to the indirect transition in the α-V2O5 film

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We investigated the magneto-optical properties of diluted magnetic semiconductors Cd 1-x Mn x Te crystals grown using a vertical Bridgman method. This material crystallizes in the zinc-blende structure for values of x < 0.82. The band-gap energy was depended on Mn mole fraction x linearly and increased with decreasing temperature. The increase of the energy gap with increasing x may be due to a decrease in the lattice constant. Faraday rotation as a function of photon energy with various Mn compositions for CdMnTe in the temperature range of 10-300 K has been measured. The Faraday rotation was increased as the photon energy increased near to that of the fundamental band gap. Verdet constant becomes larger since the effect of the sp-d exchange interaction is enhanced as the temperature is lowered.

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