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Instability of the rhodium magnetic moment as origin of the metamagnetic phase transition in alpha-FeRh

M. E. Gruner·E. Hoffmann·P. Entel
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Abstract

Based on ab initio total energy calculations we show that two magnetic states of rhodium atoms together with competing ferromagnetic and antiferromagnetic exchange interactions are responsible for a temperature induced metamagnetic phase transition, which experimentally is observed for stoichiometric alpha-FeRh. A first-principle spin-based model allows to reproduce this first-order metamagnetic transition by means of Monte Carlo simulations. Further inclusion of spacial variation of exchange parameters leads to a realistic description of the experimental magneto-volume effects in alpha-FeRh.

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M. E. Gruner, E. Hoffmann, P. Entel. 2003-01-07. Instability of the rhodium magnetic moment as origin of the metamagnetic phase transition in alpha-FeRh. https://doi.org/10.1103/physrevb.67.064415

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