Effect of an arbitrarily directed permanent magnetic field on the dynamic susceptibility of a superparamagnetic particle under the conditions of stochastic resonance

Abstract

Theoretically, based on the approximation of discrete orientations, the effect of thermal stochastic resonance is considered for a superparamagnetic particle with magnetic anisotropy of the “easy axis” type in view of an additional external permanent magnetic field applied at an arbitrary angle relative to the easy magnetization axis. The dynamic susceptibility has been calculated for a single-domain iron particle under the conditions of its modulation by a weak external radio-frequency field at various absolute values and directions of the additional permanent magnetic field vector.