An optimal analytical expression for the superparamagnetic relaxation rate under conditions of a stochastic resonance for the model of bistable systems

Abstract

A. G. 537.621.4 An analytical expression for the superparamagnetic relaxation rate of uniaxial particles modulated by a radiofrequency field is chosen that describes adequately the magnetic moment dynamics under conditions of a stochastic resonance in the approximation of discrete orientations. The complex magnetic susceptibility components are calculated for a weak external variable field. A comparison is made with the results of numerical modeling based on a solution of the Fokker-Planck equation with a periodic drift term.