Observation of Hysteresis at Spin-Flop Transition Induced by a Pulsed Magnetic Field

The results of diffraction research of the spin-flop transitions in α-Fe2O3 and Cr2O3 performed on the SNIM-2 spectrometer of the IBR-2 pulsed reactor with the use of a pulsed magnetic field are presented. The field pulses had a sinusoidal form with a time duration of 400-1000 μs. The hysteresis dependences of the scattering intensity on the field value were obtained. In the case of hematite at amplitude changes of the magnetic pulses the hysteresis loop takes its utmost shape and width, which does not change with further increases in amplitude. The width of the utmost loop is almost one order less than the theoretical range of metastability of the phase states. At a decrease in temperature the width of the utmost loop decreases. In the case of Cr2O3 the hysteresis is observed at magnetic field amplitudes, which do not reach the critical value for phase transition. This testifies to a delay of the turning processor sublattice magnetization in the initial phase state. 11 refs., 12 figs