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arXiv · 1201.2268

Frequency domain studies of current-induced magnetization dynamics in single magnetic-layer nanopillars

N. Müsgens·S. Fahrendorf·T. Maassen·A. Heiss·J. Mayer·B. Özyilmaz·B. Beschoten·G. Güntherodt
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Abstract

Spin transfer torque-induced high-frequency dynamics of single thin cobalt-layer nanopillars of circular and elliptical shape have been observed directly. Two types of precessional modes can be identified as a function of magnetic field perpendicular to the layer plane, excited for negative current polarity only. They are assigned to vortex-core and transverse spin-wave excitations, which corroborate recent model predictions. The observed narrow linewidth of 4 MHz at room temperature indicates the high coherence of the magnetic excitations.

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N. Müsgens, S. Fahrendorf, T. Maassen, A. Heiss, J. Mayer, B. Özyilmaz, B. Beschoten, G. Güntherodt. 2012-01-11. Frequency domain studies of current-induced magnetization dynamics in single magnetic-layer nanopillars. https://arxiv.org/abs/1201.2268

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