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arXiv · 1412.8402

Thermal-history dependent magnetoelastic transition in (Mn,Fe)2(P,Si)

X. F. Miao·L. Caron·Z. Gercsi·A. Daoud-Aladine·N. H. van Dijk·K. G. Sandeman·E. Bruck
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Abstract

The thermal-history dependence of the magnetoelastic transition in (Mn,Fe)2(P,Si) compounds has been investigated using high-resolution neutron diffraction. As-prepared samples display a large difference in paramagnetic-ferromagnetic (PM-FM) transition temperature compared to cycled samples. The initial metastable state transforms into a lower-energy stable state when the as-prepared sample crosses the PM-FM transition for the first time. This additional transformation is irreversible around the transition temperature and increases the energy barrier which needs to be overcome through the PM-FM transition. Consequently the transition temperature on first cooling is found to be lower than on subsequent cycles characterizing the so-called virgin effect. High temperature annealing can restore the cycled sample to the high-temperature metastable state, which leads to the recovery of the virgin effect. A model is proposed to interpret the formation and recovery of the virgin effect.

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X. F. Miao, L. Caron, Z. Gercsi, A. Daoud-Aladine, N. H. van Dijk, K. G. Sandeman, E. Bruck. 2014-12-29. Thermal-history dependent magnetoelastic transition in (Mn,Fe)2(P,Si). https://arxiv.org/abs/1412.8402

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