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Current-driven excitations in magnetic multilayers: a brief review

J. Bass·S. Urazhdin·Norman O. Birge·W. P. Pratt Jr
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Abstract

In 1996, Berger and Slonczewski independently predicted that a large enough spin-polarized dc current density sent perpendicularly through a ferromagnetic layer could produce magnetic excitations (spin-waves) or reversal of magnetization (switching). In the past few years, both current-driven switching and current-driven excitation of spin-waves have been observed. The switching is of potential technological interest for direct 'writing' of magnetic random access memory (MRAM) or magnetic media. The spin-wave generation could provide a new source of dc generated microwave radiation. We describe what has been learned experimentally about these two related phenomena, and some models being tested to explain these observations.

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J. Bass, S. Urazhdin, Norman O. Birge, W. P. Pratt Jr. 2003-10-20. Current-driven excitations in magnetic multilayers: a brief review. https://doi.org/10.1002/pssa.200304421

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