Potts-model critical manifolds revisited

Christian R. Scullard; Jesper Lykke Jacobsen

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arXiv · 1511.04374

Potts-model critical manifolds revisited

Christian R. Scullard·Jesper Lykke Jacobsen

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Abstract

We compute the critical polymials for the q-state Potts model on all Archimedean lattices, using a parallel implementation of the algorithm of (Jacobsen, J. Phys. A: Math. Theor. 47 135001) that gives us access to larger sizes than previously possible. The exact polynomials are computed for bases of size $6 \times 6$ unit cells, and the root in the temperature variable $v=e^K-1$ is determined numerically at $q=1$ for bases of size $8 \times 8$. This leads to improved results for bond percolation thresholds, and for the Potts-model critical manifolds in the real $(q,v)$ plane. In the two most favourable cases, we find now the kagome-lattice threshold to eleven digits and that of the $(3,12^2)$ lattice to thirteen. Our critical manifolds reveal many interesting features in the antiferromagnetic region of the Potts model, and determine accurately the extent of the Berker-Kadanoff phase for the lattices studied.

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Christian R. Scullard, Jesper Lykke Jacobsen. 2015-11-13. Potts-model critical manifolds revisited. https://arxiv.org/abs/1511.04374

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