Sergey V. Ovsyannikov, Vladimir V. Shchennikov, Andrew Yu. Derevskov, Vladimir I. Osotov
Pressure-treatment of semiconductors above the phase transition point is known to be a method of nanocrystals preparing. In vicinity of semiconductor-metal phase transformations a sample may be viewed as a model of heterophase (and, in particular, layers fabricated) systems; the most of the properties being dependent on the concentration and configuration of phases inclusions [1,2]. The approach to a real heterophase structures was developed by the oriented inclusions model with the variable phase configuration , and the calculations of the thermoelectric and galvanomagnetic properties were performed . The relationships between the values of resistivity (, Hall coefficient R, thermoelectric power S, magnetoresistence MR were calculated for variable configuration of phase inclusions from limiting cases of parallel to consequent electrical connection of phase.
The automated set up for simultaneous investigations of electrical, thermal and volumetric properties of thin microsamples at high pressures up to 30 GPa was developed in , and a wide amount of semiconductor substances undergoing pressure-induced phase transitions were tested by using of it . The experimental data for ternary mercury chalcogenides, lead chalcogenides and same other materials in the vicinity of pressure-induced phase transformations were found to be in well agreement with above model calculations and data of material investigation by neutron and synchrotron radiation measurements at high pressure .
The using of above approach made it possible to pick out the contribution of configuration and concentration of inclusions in the resulting properties of heterophase material observed.
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