Interfacial effects on curling mode for a coated particle

A rigorous micromagnetic study for the nucleation by the magnetization curling mode in acicular coated particles is presented. The calculated nucleation field increases with shell thickness and saturates within observable thickness. It is found that the shell uniaxial anisotropy determines the initial slope, and that the saturation level depends on both the interfacial coupling and shell anisotropy. The shell surface anisotropy will further increase the nucleation field. A very good fitting of experimental data can be obtained by this method