Cluster mean-field approach including correlation effects between clusters

Daisuke Yamamoto*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

6 Citations (Scopus)


Mean-field approaches provide a qualitative understanding of the behavior of interacting many-body systems. Weiss's molecular-field theory, in particular, has been successfully applied to the studies of various phenomena. However, since local fluctuations from the average are ignored, this simple mean-field theory does not work for systems whose distinctive behavior is caused by fluctuation effects. In the present work, we introduce a new cluster mean-field approach, which we refer to as the "correlated cluster mean-field approach", and the applications to classical and quantum spin systems are demonstrated. We divide the lattice sites into clusters consisting of several sites and include the effect of cluster-cluster correlations into the effective fields acting on the spins. In doing so, the effect of spin fluctuations can be taken into account, and our method gives qualitatively and even semiquantitatively correct results for both classical and quantum systems.

Original languageEnglish
Article number022072
JournalJournal of Physics: Conference Series
Issue numberSECTION 2
Publication statusPublished - 2010

ASJC Scopus subject areas

  • Physics and Astronomy(all)

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