Magnetoresistance effect in anion-substituted manganese chalcogenides

Abstract

The electric and magnetic properties of anion-substituted antiferromagnetic MnSe1−xTex (0.1 ≤ x ≤ 0.4) semiconductors in the 77–700 K temperature range and magnetic fields under 1 T are studied. In the MnSe1−xTex solid solutions, negative magnetoresistance in the vicinity of the Néel temperature for x = 0.1 and for composition with x = 0.2 in the paramagnetic range below 270 K is revealed. A dependence of the magnetic susceptibility versus the prehistory of the samples is found. The model of localized spin-polarized electrons with the localization radius depending on the magnetic field is proposed for x = 0.1. In the paramagnetic range, the negative magnetoresistance and the behavior of magnetic moment are a result of orbital glass formation.