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Critical behaviour and Scaling functions for the three-dimensional O(6) spin model with external field

Sven Holtmann·Thomas Schulze
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Abstract

We numerically investigate the three-dimensional O(6) model on 12^3 to 120^3 lattices. From Binder's cumulant at vanishing magnetic field we obtain the critical coupling J_c=1.42865(5) and verify this value with the χ^2-method. The universal value of Binder's cumulant at this point is g_r(J_c)=-1.94456(10). At the critical coupling we find the critical exponents ν=0.818(5), β=0.425(2) and γ=1.604(6) from a finite size scaling analysis. We also determine the finite-size-scaling function on the critical line and the equation of state. Our O(6)-result for the equation of state is compared to the Ising, O(2) and O(4) results.

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Sven Holtmann, Thomas Schulze. 2003-01-16. Critical behaviour and Scaling functions for the three-dimensional O(6) spin model with external field. https://doi.org/10.1142/9789812704498_0040

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