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Alloys between tin and tin telluride have been prepared and their thermal conductivity has been measured in the temperature range ~90–300 K. We have determined the lattice (χl) and electron (χel) contributions to the thermal conductivity of the alloys and their thermal resistivity due to structural defects (Sn vacancies and defects). We assume that, at low excess Sn concentrations, Sn atoms form electroneutral complexes with Sn vacancies, leading to a reduction in χl and χel. At high concentrations, Sn atoms fill vacancies, leading to an increase in χl. [ABSTRACT FROM AUTHOR]

The photothreshold of an α-GeS layered crystal is calculated from first principles based on the functional density method depending on its thickness. Two neighboring crystal plates consisting of several layers are separated by vacuum 4 layers thick, which corresponds to the doublet unit cell size of a bulk crystal. It is shown that the magnitude of the photothreshold is almost invariable with a crystal thickness larger than 10 layers. [ABSTRACT FROM AUTHOR]

The thermal conductivity of homogeneous crystalline SnMnTe samples has been measured in the temperature range 90-305 K. We have determined their electron and lattice thermal conductivities and their thermal resistivity due to structural defects. The results demonstrate that the electron thermal conductivity reaches ~50% of the total thermal conductivity in some of the samples and that structural defects make an appreciable contribution to the thermal resistivity of the crystals. [ABSTRACT FROM AUTHOR]

We have studied the effect of annealing on the electrical conductivity σ and thermoelectric power α of SnTe crystals. The results indicate that the temperature dependences of σ and α for both the unannealed and annealed SnTe crystals, as well as the effect of annealing on these parameters, are adequately accounted for in terms of a model that considers two valence bands separated by an energy gap. [ABSTRACT FROM AUTHOR]

We have studied the effect of excess tellurium atoms (up to 0.5 at %) on the thermal conductivity of single-crystal PbMnTe ( x = 0.04) samples annealed at 570K for 120 h. We have evaluated the lattice and electron thermal conductivities of the samples, their additional thermal resistance due to structural defects, and the coefficient in the expression for the effective phonon scattering cross section. We assume that some of the excess Te atoms fill lead vacancies, thereby reducing the effective phonon scattering cross section. [ABSTRACT FROM AUTHOR]