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arXiv · 0812.2585

Multicritical Behavior in a Random-Field Ising Model under a Continuous-Field Probability Distribution

Octavio R. Salmon·Nuno Crokidakis·Fernando D. Nobre
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Abstract

A random-field Ising model that is capable of exhibiting a rich variety of multicritical phenomena, as well as a smearing of such behavior, is investigated. The model consists of an infinite-range-interaction Ising ferromagnet in the presence of a triple-Gaussian random magnetic field, which is defined as a superposition of three Gaussian distributions with the same width $σ$, centered at H=0 and $H=\pm H_{0}$, with probabilities $p$ and $(1-p)/2$, respectively. Such a distribution is very general and recovers as limiting cases, the trimodal, bimodal, and Gaussian probability distributions.

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Octavio R. Salmon, Nuno Crokidakis, Fernando D. Nobre. 2008-12-13. Multicritical Behavior in a Random-Field Ising Model under a Continuous-Field Probability Distribution. https://doi.org/10.1088/0953-8984%2F21%2F5%2F056005

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