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Stochastic theory of spin-transfer oscillator linewidths

Joo-Von Kim
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Abstract

We present a stochastic theory of linewidths for magnetization oscillations in spin-valve structures driven by spin-polarized currents. Starting from a nonlinear oscillator model derived from spin-wave theory, we derive Langevin equations for amplitude and phase fluctuations due to the presence of thermal noise. We find that the spectral linewidths are inversely proportional to the spin-wave intensities with a lower bound that is determined purely by modulations in the oscillation frequencies. Reasonable quantitative agreement with recent experimental results from spin-valve nanopillars is demonstrated.

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Joo-Von Kim. 2006-03-01. Stochastic theory of spin-transfer oscillator linewidths. https://doi.org/10.1103/physrevb.73.174412

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