Non-linear dynamic response of superparamagnetic nanoparticles

Yu. L. RaikherCorresponding Author Contact Information, E-mail The Corresponding Author and V. I. Stepanov

Institute of Continuous Media Mechanics, Ural Division of RAS, Perm 614013, Russia

Available online 24 June 2003.


Odd-order dynamic magnetic susceptibilities of an assembly of single-domain uniaxial particles in the low-temperature limit are considered. The solution of the micromagnetic Fokker–Planck equation is presented in the form of asymptotic series with respect to the parameter small sigma, Greek that is the ratio of the anisotropy energy barrier height to the thermal energy. The expressions for the set of susceptibilities up to the fifth order are presented for the case of an assembly of particles randomly oriented in a solid matrix. The validity of the derived asymptotic representation in a wide range of small sigma, Greek is proved by comparison with the numerical solution of the Fokker–Planck equation.

Author Keywords: Superparamagnetic particles; Magnetic susceptibilities; Higher harmonics generation

Corresponding Author Contact InformationCorresponding author.