Inverted current-driven switching in Fe(Cr)/Cr/Fe(Cr) nanopillars

Current-driven excitations in symmetric magnetic nanopillars.

We study experimentally the current-driven magnetic excitations in symmetric Co/Cu/Co nanopillars. In contrast with all the previous observations where the current of only one polarity is capable of exciting a multilayer system saturated by an externally applied magnetic field, we observe that both polarities of the applied current trigger excitations in a symmetric multilayer. This may indicat...

Current-driven dynamics of domain walls constrained in ferromagnetic nanopillars

We investigate the effects of an electric current on the domain wall formed inside a cylindrical ferromagnetic nanopillar as a consequence of the pinning of the magnetization at its ends. We first present the results of three-dimensional and one-dimensional micromagnetic simulations and show that the system approaches a stationary equilibrium, where the domain wall is compressed in the directio...

Current-driven switching of magnetic layers

The switching of magnetic layers is studied under the action of a spin current in a ferromagnetic metal– nonmagnetic metal–ferromagnetic metal spin valve. We find that the main contribution to the switching comes from the nonequilibrium exchange interaction between the ferromagnetic layers. This interaction defines the magnetic configuration of the layers with minimum energy and establishes the...

Micromagnetic simulations of current-induced magnetization switching in Co/Cu/Co nanopillars

We studied the current-induced magnetic switching in Co/Cu/Co nanopillars with an in-plane magnetization traversed by a perpendicular-to-plane spin-polarized current. The Landau-LifshitzGilbert equation incorporating the spin transfer torque STT effect was employed. Magnetization switching was found to take place when the current density exceeds a threshold. It is accompanied by drastic oscilla...

Spin-transfer switching in spin valve nanopillars RESEARCH SEMESTER REPORT