Computer simulation of the thermal stability in perpendicular recording media using the thermal acceleration method

The thermal acceleration method was applied to a micromagnetic simulator to investigate the thermal stability of recorded magnetization in a high-density magnetic recording medium. In order to estimate the thermal stability with high accuracy, a correct acceleration temperature was obtained by using the attempt frequency acquired from the remanent coercive forces as a function of the pulse time. Considering the relationship between the remanent magnetization curve and the usual magnetization curve, it was found that the coefficient of conversion from a field sweep rate to a pulse time depends on the temperature. An acceleration temperature without considering the temperature dependence of the conversion coefficient was higher than the correct value, leading to a much faster degradation of magnetization. The thermal stability of written states in longer reviewing times was estimated accurately by using the micromagnetic simulation based on our thermal acceleration method.