Investigation of transverse magnetotransport in the diluted magnetic semiconductor Hg1−xFexTe

In the diluted magnetic semiconductor Hg1−xFexTe with a low iron content (x ≤ 0.3 at. %), the Hall effect and transverse magnetoresistance were investigated over the temperature range of (1.8–150) K in magnetic fields up to 13 T. At low temperatures, p-type conductivity was observed, resulting from a resonant acceptor state located ≈7.5 meV below valence band maximum. It was found that the magnetic field dependence of the transverse magnetoresistance exhibits features indicative of the formation of an energy gap at the center of the Brillouin zone, induced by the p–d-exchange interaction between impurity holes and the magnetic moments localized on the iron ions. Estimates were made for the effective exchange interaction integral and the exchange gap in a Hg1−xFexTe sample with maximum iron content. Our findings provide support for the occurrence of hole spin polarization in Hg1−xFexTe.