Magnetic and Electrical Properties of Manganese Telluride

Abstract

The temperature dependence of the susceptibility of the antiferromagnetic compound MnTe was measured over a range of temperature between liquid nitrogen temperature and 720°C. An abrupt change in slope and a maximum of the susceptibility curve were found at 37°C and at 55°C respectively. These results are compared with the observed Néel temperatures previously reported by Squire and by Serre. A thermal hysteresis was also found above the Néel temperature, relating to the heat history of the specimen. It is shown that the susceptibility of MnTe 1+ x (0≤ x ≤1), where x is the excess content of tellurium, is explicable in terms of two phases, MnTe and MnTe 2 which posses different susceptibilities. The electrical properties, i.e., the resistivity, the thermo-emf and the Hall emf, were measured as functions of temperature. Evidence was found of anomalous behaviours at the Néel temperature for them. A large thermal hysteresis of the resistivity is also found above the Néel temperature, which suggests a change of the crystal structure at about 130°C.