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Thermal fluctuations and longitudinal relaxation of single-domain magnetic particles at elevated temperatures

D. A. Garanin·O. Chubykalo-Fesenko
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Abstract

We present numerical and analytical results for the swiching times of magnetic nanoparticles with uniaxial anisotropy at elevated temperatures, including the vicinity of T_c. The consideration is based in the Landau-Lifshitz-Bloch equation that includes the relaxation of the magnetization magnitude M. The resulting switching times are shorter than those following from the naive Landau-Lifshitz equation due to (i) additional barrier lowering because of the reduction of M at the barrier and (ii) critical divergence of the damping parameters.

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D. A. Garanin, O. Chubykalo-Fesenko. 2004-09-14. Thermal fluctuations and longitudinal relaxation of single-domain magnetic particles at elevated temperatures. https://doi.org/10.1103/physrevb.70.212409

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