Magnetization Reversal in Elongated Fe Nanoparticles
arXiv:cond-mat/0505356 · doi:10.1103/PhysRevB.71.214425
Abstract
Magnetization reversal of individual, isolated high-aspect-ratio Fe nanoparticles with diameters comparable to the magnetic exchange length is studied by high-sensitivity submicron Hall magnetometry. For a Fe nanoparticle with diameter of 5 nm, the magnetization reversal is found to be an incoherent process with localized nucleation assisted by thermal activation, even though the particle has a single-domain static state. For a larger elongated Fe nanoparticle with a diameter greater than 10 nm, the inhomogeneous magnetic structure of the particle plays important role in the reversal process.
6 pages, 6 figures, to appear in Phys. Rev. B (2005)