Journal of Physics A Mathematical and General

Fluctuations in dilute antiferromagnets: Curie-Weiss models

João Amaro de Matos, J. A. Baêta Segundo, J F Perez

Published May 21, 1992• 3 citations

Abstract

The authors compute the fluctuations of the order parameter in the Curie-Weiss version of a site-dilute antiferromagnet. Their results show: (i) Gaussian fluctuations away from criticality or at a first-order critical point with sample and thermal fluctuations contributing in same order; (ii) Non-Gaussian fluctuations with critical exponents modified by the presence of dilution at the second-order critical point. In this case sample-induced fluctuations are enhanced to dominate over the thermal ones. Critical exponents are the same as in the Curie-Weiss random field Ising model.

DOI: 10.1088/0305-4470/25/10/011

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