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A Theory for Spin Glass Phenomena in Interacting Nanoparticle Systems

Derek Walton
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Abstract

Dilute magnetic nanoparticle systems exhibit slow dynamics [1] due to a broad distribution of relaxation times that can be traced to a correspondingly broad distribution of particle sizes [1]. However, at higher concentrations interparticle interactions lead to a slow dynamics that is qualitatively indistinguishable from that dislayed by atomic spin glasses. A theory is derived below that accounts quantitatively for the spin-glass behaviour. The theory predicts that if the interactions become too strong the spin glass behaviour disappears. This conclusion is in agreement with preliminary experimental results.

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Derek Walton. 2006-08-31. A Theory for Spin Glass Phenomena in Interacting Nanoparticle Systems. https://arxiv.org/abs/cond-mat/0608696

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