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arXiv · 1804.07228

Ferromagnetic phases due to competing short- and long-range interactions in the spin-S Blume-Capel model

Octavio Daniel Rodriguez Salmon·Minos Adão Neto·Francisco Dinóla Neto·Denis Américo Murillo Pariona·Justo Rojas Tapia
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Abstract

We broaden the study of the statistical physics of the spin-$S$ Blume-Capel model with ferromagnetic mean-field interactions $J$ in competition with short-range antiferromagnetic interactions $K$ in a linear chain in the thermodynamic limit. This work describes the critical behavior of the model when the $S$ takes a half integer and an integer value. In both cases the phase diagrams exhibit new ferromagnetic phases (for certain values of $K$) enclosed by branches emerging from the first-order frontiers of the pure ferromagnetic model. For finite temperatures the complex topologies were obtained by numerical minimization of the free energy.

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Octavio Daniel Rodriguez Salmon, Minos Adão Neto, Francisco Dinóla Neto, Denis Américo Murillo Pariona, Justo Rojas Tapia. 2018-04-19. Ferromagnetic phases due to competing short- and long-range interactions in the spin-S Blume-Capel model. https://doi.org/10.1016/j.physleta.2018.09.004

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