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Updated: May 30, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Alternating current driven instability in magnetic junctions.
1V A Kotelnikov Institute of Radio Engineering and Electronics of the Russian Academy of Sciences, Fryazino 141190, Russia.
Summary
High-frequency alternating current can destabilize spin-valve magnetic junctions. Parametric resonance occurs near the free layer
Area of Science:
- Condensed matter physics
- Spintronics
- Magnetism
Background:
- Spin-valve magnetic junctions are crucial for magnetic sensors and memory devices.
- Understanding their stability under external stimuli is essential for device performance.
- High-frequency currents can introduce complex dynamics in magnetic systems.
Purpose of the Study:
- To investigate the stability of spin-valve magnetic junctions under alternating (high-frequency) current.
- To analyze the conditions leading to instability, including parametric resonance.
- To compare the stability of parallel and antiparallel magnetic configurations.
Main Methods:
- Theoretical analysis of spin-valve dynamics.
- Macrospin approximation to model magnetic fluctuations.
- Investigation of stability with respect to small perturbations.
- Analysis of parametric resonance phenomena.
Main Results:
- Alternating current can lead to instability in both parallel and antiparallel spin-valve configurations.
- Parametric resonance occurs when the current frequency matches the free layer's eigenfrequency.
- The antiparallel configuration exhibits instability even under non-resonant conditions.
- The threshold current density for instability is comparable to DC switching current densities.
Conclusions:
- High-frequency alternating currents pose a significant factor in spin-valve magnetic junction stability.
- Parametric resonance is a key mechanism for current-induced instability.
- Careful consideration of operating frequencies is necessary to prevent unwanted switching in spintronic devices.
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