Article

High-temperature expansions through order 24 for the two-dimensional classical XY model on the square lattice

Physical review. B, Condensed matter (Impact Factor: 3.77). 11/2007; DOI: 10.1103/PhysRevB.76.092406
Source: arXiv

ABSTRACT The high-temperature expansion of the spin-spin correlation function of the two-dimensional classical XY (planar rotator) model on the square lattice is extended by three terms, from order 21 through order 24, and analyzed to improve the estimates of the critical parameters.

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    ABSTRACT: The high-temperature expansions for the spin-spin correlation function of the two-dimensional classical XY (planar rotator) model are extended by two terms, from order 24 through order 26, in the case of the square lattice, and by five terms, from order 15 through order 20, in the case of the triangular lattice. The data are analyzed to improve the current estimates of the critical parameters of the models.
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