Cluster size effects in the magnetic properties of Fe$_p$-Al$_{q=1-p}$ alloys

João B. Santos-Filho; Alan V. Santos; Tatiana S. de Araujo Batista; João A. Plascak

doi:10.1016/j.jmmm.2019.166262

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arXiv · 1912.02514

Cluster size effects in the magnetic properties of Fe$_p$-Al$_{q=1-p}$ alloys

João B. Santos-Filho·Alan V. Santos·Tatiana S. de Araujo Batista·João A. Plascak

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Abstract

A spin-1/2 Ising model, defined in the body centered cubic lattice, is used to describe some of the thermodynamic properties of Fe$_p$-Al$_q$ alloys, with $p+q=1$. The model assumes, besides the nearest-neighbor exchange coupling, the existence of further next-nearest-neighbor superexchange interactions, where the latter ones depend on the aluminum atoms cluster size. The Ising system so considered is studied by employing Monte Carlo simulations, using a hybrid algorithm consisting of one single-spin Metropolis move together with one single-cluster Wolff algorithm allied, in addition, with single histograms procedures and finite-size scaling techniques. Quite good fits to the experimental results of the ordering critical temperature, as a function of Al concentration in the range $0\le q<0.7$, are obtained and compared to more recent theoretical approaches done on the same alloys.

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BibTeX RIS

João B. Santos-Filho, Alan V. Santos, Tatiana S. de Araujo Batista, João A. Plascak. 2019-12-05. Cluster size effects in the magnetic properties of Fe$_p$-Al$_{q=1-p}$ alloys. https://doi.org/10.1016/j.jmmm.2019.166262

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