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Spin-transfer-driven ferromagnetic resonance of individual nanomagnets

J. C. Sankey·P. M. Braganca·A. G. F. Garcia·I. N. Krivorotov·R. A. Buhrman·D. C. Ralph
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Abstract

We demonstrate a technique that enables ferromagnetic resonance (FMR) measurements of the normal modes for magnetic excitations in individual nanoscale ferromagnets, smaller in volume by a factor of 1000 than can be probed by other methods. The measured peak shapes indicate two regimes of response: simple FMR and phase locking. Studies of the resonance frequencies, amplitudes, and linewidths as a function of microwave power, DC current, and magnetic field provide detailed new information about the exchange, damping, and spin-transfer torques that govern the dynamics in magnetic nanostructures.

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J. C. Sankey, P. M. Braganca, A. G. F. Garcia, I. N. Krivorotov, R. A. Buhrman, D. C. Ralph. 2006-02-04. Spin-transfer-driven ferromagnetic resonance of individual nanomagnets. https://doi.org/10.1103/physrevlett.96.227601

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