Current-induced magnetization excitation in a pseudo-spin-valve with in-plane anisotropy

Abstract

We study the magnetization dynamics of a pseudo-spin-valve structure with in-plane anisotropy, which is induced by the passage of a perpendicular-to-plane spin-polarized current. The magnetization dynamics is described by a modified Landau-Lifshitz-Gilbert (LLG) equation, which incorporates two spin torque terms. The simulation results reveal two magnetization excitation modes: (a) complete magnetization reversal and (b) persistent spin precession. The existence of these dual modes may be explained in terms of the competition between the four terms of the modified LLG equation. Our results give indications to the optimal operating conditions for current-induced magnetization dynamics for possible device applications. © 2008 American Institute of Physics.