Abstract
A system of equations is derived for moments [averages of spherical harmonics 〈Y l,m 〉(t)] that determine the dynamics of the magnetization M of a superparamagnetic particle in a fluctuating field. The system is derived by representing the Gilbert equation in a fluctuating field, and the corresponding Fokker-Planck equation for the distribution function of M, in terms of angular momentum operators, which in turn makes it possible to express the coefficients of the system of moment equations in terms of Clebsch-Gordan coefficients.
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Fiz. Tverd. Tela (St. Petersburg) 41, 2020–2027 (November 1999)
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Kalmykov, Y.P., Titov, S.V. Calculating coefficients for a system of moment equations used to describe the magnetization kinetics of a superparamagnetic particle in a fluctuating field. Phys. Solid State 41, 1854–1861 (1999). https://doi.org/10.1134/1.1131113
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DOI: https://doi.org/10.1134/1.1131113