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Vortex polarity switching by a spin--polarized current

Jean-Guy Caputo·Yuri Gaididei·Franz G. Mertens·Denis D. Sheka
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Abstract

The spin-transfer effect is investigated for the vortex state of a magnetic nanodot. A spin current is shown to act similarly to an effective magnetic field perpendicular to the nanodot. Then a vortex with magnetization (polarity) parallel to the current polarization is energetically favorable. Following a simple energy analysis and using direct spin--lattice simulations, we predict the polarity switching of a vortex. For magnetic storage devices, an electric current is more effective to switch the polarity of a vortex in a nanodot than the magnetic field.

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Jean-Guy Caputo, Yuri Gaididei, Franz G. Mertens, Denis D. Sheka. 2006-09-28. Vortex polarity switching by a spin--polarized current. https://doi.org/10.1103/physrevlett.98.056604

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