Angle dependence of the switching field of recording media at finite temperatures

A combined micromagnetic and nudged elastic band method was used to investigate the utility of a one-grain model in describing the switching field of CoCrPt perpendicular recording media as a function of applied field angle at finite temperatures of 150 K, 292 K and 350 K. The effect of grain diameter, attempt frequency, and thermal activation on the switching field were investigated. The results of the simulations show good agreement with vector vibrating sample magnetometer measurements on well segregated, single layer CoCrPt-SiO_x recording media and demonstrate that thermal activation modifies the Stoner-Wohlfarth angle dependency of the switching field by reducing the depth of the minimum that occurs at 45°.