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arXiv · 2204.00047

Multicanonical simulations of the 2D spin-$1$ Baxter-Wu model in a crystal field

Nikolaos G. Fytas·Alexandros Vasilopoulos·Erol Vatansever·Anastasios Malakis·Martin Weigel
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Abstract

We investigate aspects of universality in the two-dimensional (2D) spin-$1$ Baxter-Wu model in a crystal field $\Delta$ using a parallel version of the multicanonical algorithm employed at constant temperature $T$. A detailed finite-size scaling analysis in the continuous regime of the $\Delta-T$ phase diagram of the model indicates that the transition belongs to the universality class of the $4$-state Potts model. The presence of first-order-like finite-size effects that become more pronounced as one approaches the pentacritical point of the model is highlighted and discussed.

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Nikolaos G. Fytas, Alexandros Vasilopoulos, Erol Vatansever, Anastasios Malakis, Martin Weigel. 2022-03-31. Multicanonical simulations of the 2D spin-$1$ Baxter-Wu model in a crystal field. https://doi.org/10.1088/1742-6596%2F2207%2F1%2F012008

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