Correlations in mesoscopic magnetic systems

F. Gulminelli; Ph. Chomaz

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Correlations in mesoscopic magnetic systems

F. Gulminelli·Ph. Chomaz

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Abstract

The purpose of this proposal is to study the ferro/para phase transition in a mesoscopic Ising-like lattice and in particular demonstrate the existence of a negative magnetic susceptibility in the fixed magnetization ensemble. To this aim we will use the correlation < S(r) S(r+Dr) > = < M2>/N2 where N is the total number of spins for a single cluster, M the total magnetization of the cluster, and the equality holds if we choose r0<Dr<R where r0 is the linear size of a spin site and R is the linear size of a cluster.

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F. Gulminelli, Ph. Chomaz. 2004-10-17. Correlations in mesoscopic magnetic systems. https://arxiv.org/abs/cond-mat/0410427

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