Auto-oscillation threshold, narrow spectral lines, and line jitter in spin-torque oscillators based on MgO magnetic tunnel junctions
arXiv:0810.0978 · doi:10.1063/1.3260233
Abstract
We demonstrate spin torque induced auto-oscillation in MgO-based magnetic tunnel junctions. At the generation threshold, we observe a strong line narrowing down to 6 MHz at 300K and a dramatic increase in oscillator power, yielding spectrally pure oscillations free of flicker noise. Setting the synthetic antiferromagnet into autooscillation requires the same current polarity as the one needed to switch the free layer magnetization. The induced auto-oscillations are observed even at zero applied field, which is believed to be the acoustic mode of the synthetic antiferromagnet. While the phase coherence of the auto-oscillation is of the order of microseconds, the power autocorrelation time is of the order of milliseconds and can be strongly influenced by the free layer dynamics.
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Cited by in corpus (9)
- Spin transfer nano-oscillators
- Non-white frequency noise in spin torque oscillators and its effect on spectral linewidth
- Coherent microwave generation by spintronic feedback oscillator
- Intrinsic synchronization of an array of spin-torque oscillators driven by the spin-Hall effect
- Theoretical Study of Spin-Torque Oscillator with Perpendicularly Magnetized Free Layer
- Synchronization of spin-torque driven nanooscillators for point contacts on a quasi-1D nanowire: Micromagnetic simulations
- Detection of spin torque magnetization dynamics through low frequency noise
- Role of Magnetic Field in Self-Oscillation of Nanomagnet Excited by Spin Torque
- Low-non-linearity spin-torque oscillations driven by ferromagnetic nanocontacts