Electronic structure of diluted magnetic semiconductors Pb1−x−ySnxCryTe

Abstract

Abstract Galvanomagnetic effects in diluted magnetic semiconductors Pb 1− x − y Sn x Cr y Te at temperatures 4.2≤ T ≤300 K under variation of matrix composition ( x =0.06–0.235) and impurity content ( y =0.002–0.045) have been investigated. The p–n-conversion of the conductivity type, induced by the chromium doping, was observed. It is shown that in the heavily doped alloys temperature dependencies of resistivity and of the Hall coefficient have a “metallic” character, indicating pinning of the Fermi level by the chromium deep impurity level, situated in the conduction band. Free electron concentration and Fermi energy were calculated as functions of impurity concentration and of matrix composition by analyzing experimental data in the framework of the two-band Kane dispersion law. The impurity content coefficients of the free charge carrier concentration were determined and the diagram of electronic structure rearrangement under varying the alloy composition was obtained for the alloys under study.