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arXiv · 0904.1214

Time domain measurement of phase noise in a spin torque oscillator

Mark W. Keller·A. B. Kos·T. J. Silva·W. H. Rippard·M. R. Pufall
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Abstract

We measure oscillator phase from the zero crossings of the voltage vs. time waveform of a spin torque nanocontact oscillating in a vortex mode. The power spectrum of the phase noise varies with Fourier frequency $f$ as $1/f^2$, consistent with frequency fluctuations driven by a thermal source. The linewidth implied by phase noise alone is about 70 % of that measured using a spectrum analyzer. A phase-locked loop reduces the phase noise for frequencies within its 3 MHz bandwidth.

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Mark W. Keller, A. B. Kos, T. J. Silva, W. H. Rippard, M. R. Pufall. 2009-04-07. Time domain measurement of phase noise in a spin torque oscillator. https://doi.org/10.1063/1.3133356

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