Temperature-induced magnetization reversal in BiFe_0.5Mn_0.5O₃ synthesized at high pressure

Abstract

BiFe_0.5Mn_0.5O₃ could be stabilized in the perovskite structure by preparing it under high pressure and temperature. It has an orthorhombic structure with a possible ordered arrangement of Fe and Mn double rows and shows a magnetic ordering at high temperature (270 K). Low-temperature isothermal-magnetization measurements indicate the ground state to be antiferromagnetic with a spin canting. Surprisingly, it exhibits magnetization reversal at low applied fields below a compensation temperature, T^∗. Below T^∗, the sign of the magnetization can be switched between negative and positive value reversibly by increasing and decreasing the field. Magnetization reversal in this oxide seems to result from a competition between single-ion magnetocrystalline anisotropy and antisymmetric Dzyaloshinsky-Moriya interactions.