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arXiv · 2404.07079

Anisotropic Ising model in d+s dimensions

Estevão F. Borel·Aldo Procacci·Rémy Sanchis·Roger W. C. Silva
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Abstract

In this note, we consider the asymmetric nearest neighbor ferromagnetic Ising model on the $(d+s)$-dimensional unit cubic lattice $\Z^{d+s}$, at inverse temperature $\beta=1$ and with coupling constants $J_s>0$ and $J_d>0$ for edges of $\Z^s$ and $\Z^d$, respectively. We obtain a lower bound for the critical curve in the phase diagram of $(J_s,J_d)$. In particular, as $J_d$ approaches its critical value from below, our result is directly related to the so-called dimensional crossover phenomenon.

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Estevão F. Borel, Aldo Procacci, Rémy Sanchis, Roger W. C. Silva. 2024-04-10. Anisotropic Ising model in d+s dimensions. https://arxiv.org/abs/2404.07079

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