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arXiv · 0912.3650

Oscillatory transient regime in the forced dynamics of a spin torque nano-oscillator

Yan Zhou·Vasil Tiberkevich·Ezio Iacocca·Andrei Slavin·Johan Akerman
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Abstract

We demonstrate that the transient non-autonomous dynamics of a spin torque nano-oscillator (STNO) under a radio-frequency (rf) driving signal is qualitatively different from the dynamics described by the Adler model. If the external rf current $I_{rf}$ is larger than a certain critical value $I_{cr}$ (determined by the STNO bias current and damping) strong oscillations of the STNO power and phase develop in the transient regime. The frequency of these oscillations increases with $I_{rf}$ as $\propto\sqrt{I_{rf} - I_{cr}}$ and can reach several GHz, whereas the damping rate of the oscillations is almost independent of $I_{rf}$. This oscillatory transient dynamics is caused by the strong STNO nonlinearity and should be taken into account in most STNO rf applications.

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Yan Zhou, Vasil Tiberkevich, Ezio Iacocca, Andrei Slavin, Johan Akerman. 2009-12-18. Oscillatory transient regime in the forced dynamics of a spin torque nano-oscillator. https://doi.org/10.1103/physrevb.82.012408

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