Current-Induced Magnetization Reversal in High Magnetic Fields in Co/Cu/Co Nanopillars

摘要

Current-induced magnetization dynamics in Co/Cu/Co trilayer nanopillars(~100nm in diameter) has been studied experimentally for large applied fieldsperpendicular to the layers. An abrupt and hysteretic increase in dynamicresistance is observed at high current densities for one polarity of thecurrent, comparable to the giant magnetoresistance effect observed at lowfields. A micromagnetic model, that includes a spin-transfer torque, suggeststhat the current induces a complete reversal of the thin Co layer to alignmentantiparallel to the applied field-that is, to a state of maximum magneticenergy.