Galvanomagnetic properties of Pb1−xSnxTe polycrystalline pressed samples

Pressed samples of Pb1−xSnxTe, with x=0.0, 0.1, 0.2, 0.3 and 0.4 were prepared. Elemental analysis showed the presence of excess tellurium in these samples. X-ray diffraction analysis confirmed the polycrystalline structure. The calculated unit cell dimension, (a in Å), decreases with the tin substitution in lead telluride. Electrical resistivity, ρ, decreased from 1.3 to 6.3×10−4 Ω cm at room temperature, when “x” increased. From the hot probe test all the samples were of p-type conduction at room temperature (300 K). The hole concentration, p, increased from 2.35×1016 to 3.6×1019 cm−3, at room temperature, while the value of the Hall mobility oscillated between 100 and 290 cm2/V s. The relation between the electrical resistivity and temperature was studied in the temperature range 100–450 K. The dependence of the Hall coefficient RH on magnetic field was studied for samples at temperatures of 100, 200 and 400 K, in the range of magnetic field 0.1–1.0 T. It was observed that RH is nearly magnetic field independent. The magnetoresistance, MR, was studied at different magnetic field intensities, H, and temperatures. The MR effect became considerable as the temperature decreased from 400 to 100 K. When MR was represented versus temperature, T, a straight line relationship was obtained. Also when MR and μHH were plotted on a log–log scale, a straight line relationship was obtained, showing that MR∝(μHH)2.