Magnetic interactions between nanoparticles

Steen Mørup, Mikkel Fougt Hansen, Cathrine Frandsen

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

We present a short overview of the influence of inter-particle interactions on the properties of magnetic nanoparticles. Strong magnetic dipole interactions between ferromagnetic or ferrimagnetic particles, that would be superparamagnetic if isolated, can result in a collective state of nanoparticles. This collective state has many similarities to spin-glasses. In samples of aggregated magnetic nanoparticles, exchange interactions are often important and this can also lead to a strong suppression of superparamagnetic relaxation. The temperature dependence of the order parameter in samples of strongly interacting hematite nanoparticles or goethite grains is well described by a simple mean field model. Exchange interactions between nanoparticles with different orientations of the easy axes can also result in a rotation of the sub-lattice magnetization directions.
Original languageEnglish
JournalBeilstein Journal of Nanotechnology
Volume1
Pages (from-to)182-190
ISSN2190-4286
DOIs
Publication statusPublished - 2010

Cite this