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Current-driven Magnetization Reversal and Spin Wave Excitations in Co/Cu/Co Pillars

J. A. Katine·F. J. Albert·R. A. Buhrman·E. B. Myers·D. C. Ralph
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Abstract

Using thin film pillars ~100 nm in diameter, containing two ferromagnetic Co layers of different thicknesses separated by a paramagnetic Cu spacer, we examine effects of torques due to spin-polarized currents flowing perpendicular to the layers. In accordance with spin-transfer theory, spin-polarized electrons flowing from the thin to the thick Co layer can switch the magnetic moments of the layers antiparallel, while a reversed electron flow causes switching to a parallel state. When large magnetic fields are applied, the current no longer fully reverses the magnetic moment, but instead stimulates spin-wave excitations.

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J. A. Katine, F. J. Albert, R. A. Buhrman, E. B. Myers, D. C. Ralph. 1999-08-16. Current-driven Magnetization Reversal and Spin Wave Excitations in Co/Cu/Co Pillars. https://doi.org/10.1103/physrevlett.84.3149

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