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arXiv · 1106.3424

Exact spin-spin correlation function for the zero-temperature random-field Ising model

T. P. Handford·F. J. Perez-Reche·S. N. Taraskin
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Abstract

An exact expression for the spin-spin correlation function is derived for the zero-temperature random-field Ising model defined on a Bethe lattice of arbitrary coordination number. The correlation length describing dynamic spin-spin correlations and separated from the intrinsic topological length scale of the Bethe lattice is shown to diverge as a power law at the critical point. The critical exponents governing the behaviour of the correlation length are consistent with the mean-field values found for a hypercubic lattice with dimension greater than the upper critical dimension.

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T. P. Handford, F. J. Perez-Reche, S. N. Taraskin. 2012-04-17. Exact spin-spin correlation function for the zero-temperature random-field Ising model. https://doi.org/10.1088/1742-5468%2F2012%2F01%2Fp01001

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