Path Integral Approach to Stochastic Magnetization Dynamics in Uniaxial Ferromagnetic Nanoparticles

We study stochastic magnetization dynamics in uniformly magnetized uniaxial particles. The solution of the Fokker-Planck equation associated with the problem is expressed as a Wiener-type Path Integral. This path integral is then approximately computed in the limit of small noise by using action minimization technique. This analytical technique is used to compute typical durations of thermal induced transitions between opposite magnetization orientations. The analytical results are compared with numerical integration of the Landau-Lifshitz equation describing the stochastic magnetization dynamics.