Understanding the current-induced magnetization dynamics in the presence of large magnetic fields

We have theoretically studied the magnetization behavior in the magnetic trilayer nanostructures under the influence of spin-transfer torque using the Landau-Lifshitz-Gilbert equation. The focus is the coherent transition of the magnetization from a static state to another static state induced by the spin current even in the presence of a large applied field. Based on the study, the experimental observations, which were thought to be due to spin-wave excitations previously, can be directly and quantitatively explained by the out-of-plane static states of the magnetization induced by the spin-current in the presence of large in-plane magnetic fields in the range of several Teslas. (C) 2005 Elsevier B.V. All rights reserved.