Phase diagram of magnetization switching in a nanostructured magnetic thin film

Abstract

The magnetization switching behavior in a nanostructured magnetic thin film, under combined in-plane fields along the longitudinal and the transverse directions, is investigated both analytically and numerically. Two critical curves under a static and a dynamic condition are calculated analytically by using an equation for the total energy. The analytically calculated critical curves are compared with the micromagnetic simulation results for the switching phase diagrams of nonswitching, incoherent switching, and coherent switching. The comparison indicates that the dynamic critical curve is the boundary separating the nonswitching from the incoherent switching, while the static critical curve acts as the boundary between the incoherent switching and the coherent switching. The present results indicate that the switching phase diagram can be constructed analytically with the use of a total energy equation. The analytically calculated critical curves are less accurate in the presence of the simplifying assumptions of a single and in-plane domain state for a small angle between the applied magnetic field and the easy axis. In this case, an accurate value of the anisotropy energy, an input to the total energy equation, must be accurately estimated by micromagnetic simulation. (C) 2010 American Institute of Physics. [doi:10.1063/1.3484047]