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arXiv · 0810.4109

Magnetic hyperthermia in single-domain monodisperse FeCo nanoparticles: Evidences for Stoner-Wohlfarth behaviour and large losses

L. -M. Lacroix·R. Bel Malaki·J. Carrey·S. Lachaize·G. F. Goya·B. Chaudret·M. Respaud
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Abstract

We report on hyperthermia measurements on a colloidal solution of 15 nm monodisperse FeCo nanoparticles (NPs). Losses as a function of the magnetic field display a sharp increase followed by a plateau, which is what is expected for losses of ferromagnetic single-domain NPs. The frequency dependence of the coercive field is deduced from hyperthermia measurement and is in quantitative agreement with a simple model of non-interacting NPs. The measured losses (1.5 mJ/g) compare to the highest of the literature, though the saturation magnetization of the NPs is well below the bulk one.

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L. -M. Lacroix, R. Bel Malaki, J. Carrey, S. Lachaize, G. F. Goya, B. Chaudret, M. Respaud. 2008-10-22. Magnetic hyperthermia in single-domain monodisperse FeCo nanoparticles: Evidences for Stoner-Wohlfarth behaviour and large losses. https://doi.org/10.1063/1.3068195

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