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Generation linewidth of an auto-oscillator with a nonlinear frequency shift: Spin-torque nano-oscillator

Joo-Von Kim·Vasil Tiberkevich·Andrei N. Slavin
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Abstract

It is shown that the generation linewidth of an auto-oscillator with a nonlinear frequency shift (i.e. an auto-oscillator in which frequency depends on the oscillation amplitude) is substantially larger than the linewidth of a conventional quasi-linear auto-oscillator due to the renormalization of the phase noise caused by the nonlinearity of the oscillation frequency. The developed theory, when applied to a spin-torque nano-contact auto-oscillator, predicts a minimum of the generation linewidth when the nano-contact is magnetized at a critical angle to its plane, corresponding to the minimum nonlinear frequency shift, in good agreement with recent experiments.

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Joo-Von Kim, Vasil Tiberkevich, Andrei N. Slavin. 2007-06-26. Generation linewidth of an auto-oscillator with a nonlinear frequency shift: Spin-torque nano-oscillator. https://doi.org/10.1103/physrevlett.100.017207

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