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arXiv · 0710.0495

Lineshape distortion in a nonlinear auto-oscillator near generation threshold: Application to spin-torque nano-oscillators

Joo-Von Kim·Q. Mistral·C. Chappert·V. S. Tiberkevich·A. N. Slavin
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Abstract

The lineshape in an auto-oscillator with a large nonlinear frequency shift in the presence of thermal noise is calculated. Near the generation threshold, this lineshape becomes strongly non-Lorentzian, broadened, and asymmetric. A Lorentzian lineshape is recovered far below and far above threshold, which suggests that lineshape distortions provide a signature of the generation threshold. The theory developed adequately describes the observed behavior of a strongly nonlinear spin-torque nano-oscillator.

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Joo-Von Kim, Q. Mistral, C. Chappert, V. S. Tiberkevich, A. N. Slavin. 2007-11-28. Lineshape distortion in a nonlinear auto-oscillator near generation threshold: Application to spin-torque nano-oscillators. https://doi.org/10.1103/physrevlett.100.167201

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