Thermal switching rate of a ferromagnetic material with uniaxial anisotropy

摘要

The field dependence of the thermal switching rate of a ferromagneticmaterial with uniaxial anisotropy was studied by solving the Fokker-Planckequation. We derived the analytical expression of the thermal switching rateusing the mean first-passage time approach, and found that Brown's formula[Phys. Rev. 130, 1677 (1963)] is applicable even in the low barrier limit byreplacing the attempt frequency with the proper factor which is expressed bythe error function.