${\text{BiFe}}_{0.5}{\text{Mn}}_{0.5}{\text{O}}_3$ 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, $T^{\ast }$. Below $T^{\ast }$, 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.

• Received 22 July 2010

DOI:https://doi.org/10.1103/PhysRevB.82.100416