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Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
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Rotating-field-driven ensembles of magnetic particles
M Belovs1, M Brics1, A Cēbers1
1MMML Laboratory, Department of Physics, University of Latvia, Jelgavas 3, Rīga LV-1002, Latvia.
Physical Review. E
|May 22, 2019
Summary
Magnetic particle ensembles exhibit complex vortex patterns when driven by rotating fields. Their dynamics reveal distinct regimes, including solid-body rotation and stick-slip motion, with a new formula aligning with experimental results.
Area of Science:
- Physics
- Materials Science
- Soft Matter Physics
Background:
- Ensembles of magnetic particles exhibit complex behaviors when subjected to external fields.
- Understanding nonequilibrium dynamics is crucial for applications in micro-robotics and data storage.
Purpose of the Study:
- To investigate vortex patterns and dynamics in magnetic particle ensembles driven by a rotating field.
- To characterize the different dynamic regimes and their dependence on field frequency.
- To develop a theoretical relation for solid-body rotation and compare it with experimental data.
Main Methods:
- Theoretical study of magnetic particle ensembles.
- Analysis of lubrication forces and their role in driving particle motion.
- Identification and characterization of distinct dynamic regimes (solid-body rotation, stick-slip motion).
Main Results:
- Lubrication forces drive ensembles into a nonequilibrium state due to unbalanced radial forces.
- Two primary dynamic regimes were identified: solid-body rotation at low frequencies and stick-slip motion at higher frequencies.
- A novel relation for angular velocity during solid-body rotation was derived and found to agree well with experimental data.
Conclusions:
- The study elucidates the complex nonequilibrium dynamics of driven magnetic particle ensembles.
- The findings provide a theoretical framework for understanding vortex formation and motion in such systems.
- The validated relation for solid-body rotation offers predictive power for experimental systems.
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