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arXiv · 0807.4617

High-temperature expansion of the magnetic susceptibility and higher moments of the correlation function for the two-dimensional XY model

H. Arisue
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Abstract

We calculate the high-temperature series of the magnetic susceptibility and the second and fourth moments of the correlation function for the XY model on the square lattice to order $β^{33}$ by applying the improved algorithm of the finite lattice method. The long series allow us to estimate the inverse critical temperature as $β_c=1.1200(1)$, which is consistent with the most precise value given previously by the Monte Carlo simulation. The critical exponent for the multiplicative logarithmic correction is evaluated to be $θ=0.054(10)$, which is consistent with the renormalization group prediction of $θ={1/16}$.

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H. Arisue. 2008-07-29. High-temperature expansion of the magnetic susceptibility and higher moments of the correlation function for the two-dimensional XY model. https://doi.org/10.1103/physreve.79.011107

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