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Magnetization noise in magnetoelectronic nanostructures

Jorn Foros·Arne Brataas·Yaroslav Tserkovnyak·Gerrit E. W. Bauer
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Abstract

By scattering theory we show that spin current noise in normal electric conductors in contact with nanoscale ferromagnets increases the magnetization noise by means of a fluctuating spin-transfer torque. Johnson-Nyquist noise in the spin current is related to the increased Gilbert damping due to spin pumping, in accordance with the fluctuation-dissipation theorem. Spin current shot noise in the presence of an applied bias is the dominant contribution to the magnetization noise at low temperatures.

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Jorn Foros, Arne Brataas, Yaroslav Tserkovnyak, Gerrit E. W. Bauer. 2005-01-13. Magnetization noise in magnetoelectronic nanostructures. https://doi.org/10.1103/physrevlett.95.016601

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