Magnetization reversal on different time-scales for ErFeO3 and NdFeO3 single crystals

Abstract

The dynamics of the magnetic moment reversal is studied for ErFeO₃ and NdFeO₃ single crystals. The reversal occurs at 41 and 5.1 K for ErFeO₃ and NdFeO₃, respectively, at a field of 300 Oe. The dynamics of the magnetization reversal process depends on the temperature at which the reversal occurs. The reversal is abrupt if the thermal energy is far higher than the energy of Zeeman splitting of the rare earth ion levels by internal fields, as observed for ErFeO₃. A gradual magnetization reversal occurs for NdFeO₃ over 64 s, when the thermal energy at the temperature of the reversal is well below the Zeeman splitting energy of Nd³⁺ spins. A mechanism for this gradual magnetization reversal is proposed in terms of the thermal re-population of Zeeman doublets of Nd³⁺ ions, the splitting energy of which continuously changes during the magnetization reversal.