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

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.

4 page, 3 figures

References in corpus (3)

• Coupling efficiency for phase locking of a spin transfer oscillator to a microwave current
• Non-linear frequency and amplitude modulation of a nano-contact spin torque oscillator
• Micromagnetic simulations of persistent oscillatory modes excited by spin-polarized current in nanoscale exchange-biased spin valves

Cited by in corpus (9)

• Phase locking dynamics of dipolarly coupled vortex-based spin transfer oscillators
• Phase locking of vortex based spin transfer oscillators to a microwave current
• Experimental demonstration of a rapid sweep-tuned spectrum analyzer with temporal resolution based on a spin-torque nano-oscillator
• Analog and digital phase modulation of spin torque nano-oscillators
• Low Power Microwave Signal Detection With a Spin-Torque Nano-Oscillator in the Active Self-Oscillating Regime
• Non-Adlerian phase slip and non stationary synchronization of spin-torque oscillators to a microwave source
• Robust synchronization of spin-torque oscillators with an LCR load
• Computing with injection-locked spintronic diodes
• Frequency locking near the gluing bifurcation: Spin-torque oscillator under periodic modulation of current