Magnetization reversal on different time-scales for ErFeO₃and NdFeO₃single crystals

The dynamics of the magnetic moment reversal is studied for ErFeO and NdFeO single crystals. The reversal occurs at 41 and 5.1 K for ErFeO and NdFeO , 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 ErFeO . A gradual magnetization reversal occurs for NdFeO over 64 s, when the thermal energy at the temperature of the reversal is well below the Zeeman splitting energy of Nd spins. A mechanism for this gradual magnetization reversal is proposed in terms of the thermal re-population of Zeeman doublets of Nd ions, the splitting energy of which continuously changes during the magnetization reversal. 3 3 3 3 3 3 3+ 3+