2003/07/18 by H. Kachkachi
Physics and Astronomy · #cond-mat.stat-mech #cond-mat.mtrl-sci
published as J. Mol. Liquids 114 (2004) 113-130 · 35 pages, 7 eps figures. Review article to appear in a special issue of J. Mol. Liquids
arxiv created 2003/07/18 · arxiv updated 2009/12/01
We review some recent results beyond the now established theory of magnetization switching of a nanoparticle within the single-spin approximation. The first extension is that of the Stoner-Wohlfarth model for magnetization static switching under applied magnetic field including the effect of temperature at long-time scales. The second concerns a generalization of the Néel-Brown model for thermoactivated dynamic magnetization switching to include the effect of exchange interaction in the framework of Langer's theory in the intermediate-to-high damping limit. We finally argue why the single-spin approximation is not appropriate for very small nanoparticles.