An Effective Three-Dimensional Micromagnetic Method and Its Application to Magnetic Tunnel Junctions

An effective three-dimensional micromagnetic method for predicting equilibrium configuration of magnetization states is presented with conjugate-gradient technique to minimize the total energy, which has a much faster convergence rate than that of the quasi-Newton method. As an application, magnetic tunnel junctions with pinholes in the ultrathin barrier are simulated. The calculated coupling field H_f increases with the pinhole density increase, corresponding to the decrease of barrier thickness. The free layer domain configuration of tunnel junction during the switching process is also demonstrated.