Brownian Rotational Motion of Ferromagnetic Nanoparticle in Liquid

Abstract

Langevin and Fokker Planck equations are considered for stochastic spherical motion of the ferromagnetic fine particle with frozen magnetic moment in a viscous carrier. Special attention devotes to the correspondence between dissipative and diffusive terms of these equations. For the case when the particle moment of inertia is negligible small, the effective system of Langevin equation for spherical coordinates is obtained. This system contains two equations with additive noises and can be readily treated numerically. We confirm our analytical finding by numerical simulation.