Critical properties of the eight-vertex model in a field

Roman Krčmár; Ladislav Šamaj

doi:10.1209/0295-5075/115/56001

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arXiv · 1610.08657

Critical properties of the eight-vertex model in a field

Roman Krčmár·Ladislav Šamaj

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Abstract

The general eight-vertex model on a square lattice is studied numerically by using the Corner Transfer Matrix Renormalization Group method. The method is tested on the symmetric (zero-field) version of the model, the obtained dependence of critical exponents on model's parameters is in agreement with Baxter's exact solution and weak universality is verified with a high accuracy. It was suggested longtime ago that the symmetric eight-vertex model is a special exceptional case and in the presence of external fields the eight-vertex model falls into the Ising universality class. We confirm numerically this conjecture in a subspace of vertex weights, except for two specific combinations of vertical and horizontal fields for which the system still exhibits weak universality.

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Roman Krčmár, Ladislav Šamaj. 2016-10-27. Critical properties of the eight-vertex model in a field. https://doi.org/10.1209/0295-5075/115/56001

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