Physics of the Solid State

, Volume 41, Issue 11, pp 1854–1861

Calculating coefficients for a system of moment equations used to describe the magnetization kinetics of a superparamagnetic particle in a fluctuating field

  • Yu. P. Kalmykov
  • S. V. Titov
Magnetism and Ferroelectricity

DOI: 10.1134/1.1131113

Cite this article as:
Kalmykov, Y.P. & Titov, S.V. Phys. Solid State (1999) 41: 1854. doi:10.1134/1.1131113


A system of equations is derived for moments [averages of spherical harmonics 〈Yl,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.

Copyright information

© American Institute of Physics 1999

Authors and Affiliations

  • Yu. P. Kalmykov
    • 1
  • S. V. Titov
    • 2
  1. 1.Centre d’Etudes FondamentalesUniversité de PerpignanFrance
  2. 2.Institute of Radio Engineering and ElectronicsRussian Academy of SciencesFryazino, Moscow DistrictRussia