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arXiv · 1411.4181

Mixed-bond spin-1 Ising model with nonlinear interactions for the Fe-Mn alloys

A. S. Freitas·Douglas F. de Albuquerque·I. P. Fittipaldi·N. O. Moreno
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Abstract

In this letter, we apply the mixed-bond spin-1 Ising model to the study of the magnetic properties of Fe-Mn alloys in the $\alpha$ phase by employing the effective field theory (EFT). Here, we suggest a new approach to the ferromagnetic coupling between nearest neighbours Fe-Fe that depends on the ratio between the Mn-Mn coupling and Fe-Mn coupling and of second power of the Mn concentration $q$ in contrast with linear dependence proposed in the other papers. Also, we propose a new probability distribution for binary alloys with mixed-bonds based on the distribution for ternary alloys and we obtain a very good agreement for all considered values of $q$ in $T-q$ plane, in particular for $q>0.11$.

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A. S. Freitas, Douglas F. de Albuquerque, I. P. Fittipaldi, N. O. Moreno. 2014-11-15. Mixed-bond spin-1 Ising model with nonlinear interactions for the Fe-Mn alloys. https://arxiv.org/abs/1411.4181

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