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arXiv · 1607.05221

Monte Carlo simulations of an Ising bilayer with non-equivalent planes

Ian Jordy Lopez Diaz·Nilton da Silva Branco
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Abstract

We study the thermodynamic and magnetic properties of an Ising bilayer ferrimagnet. The system is composed of two interacting non-equivalent planes in which the intralayer couplings are ferromagnetic while the interlayer interactions are antiferromagnetic. Moreover, one of the planes is randomly diluted. The study is carried out within a Monte Carlo approach employing the multiple histogram reweighting method and finite-size scaling tools. The occurrence of a compensation phenomenon is verified and the compensation temperature, as well as the critical temperature for the model, are obtained as functions of the Hamiltonian parameters. We present a detailed discussion of the regions of the parameter space where the compensation effect is present or absent. Our results are then compared to a mean-field-like approximation applied to the same model by Balcerzak and Sza{\l}owski (2014). Although the Monte Carlo and mean-field results agree qualitatively, our quantitative results are significantly different.

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Ian Jordy Lopez Diaz, Nilton da Silva Branco. 2016-07-18. Monte Carlo simulations of an Ising bilayer with non-equivalent planes. https://doi.org/10.1016/j.physa.2016.10.055

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