Spin-polarized current-driven switching in permalloy nanostructures

Spin-polarized current-driven switching processes in a rectangular-shaped permalloy spin valve at deep submicron dimension have been studied by means of micromagnetic modeling. The effect of the magnetostatic antiferromagnetic coupling between ferromagnetic layers has been analyzed. The antiferromagnetic coupling promotes the switching both from parallel to antiparallel transition and backward. Systematic simulations were carried out in order to determine the minimum pulse features needed to switch the magnetization of the free layer. Reversal from antiparallel to parallel state requires shorter and less intense pulses than the reciprocal transition due to the asymmetric character of the spin-polarized current torque. (c) 2005 American Institute of Physics.