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Magnetization Reversal in Elongated Fe Nanoparticles

Yongqing Li·Peng Xiong·Stephan von Molnar·Yuzo Ohno·Hideo Ohno
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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.

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Yongqing Li, Peng Xiong, Stephan von Molnar, Yuzo Ohno, Hideo Ohno. 2005-05-13. Magnetization Reversal in Elongated Fe Nanoparticles. https://doi.org/10.1103/physrevb.71.214425

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