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Updated: Jul 10, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Faraday instability of superfluid surface.
Haruka Abe1, Tetsuto Ueda, Michihiro Morikawa
1Department of Condensed Matter Physics, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro, Tokyo 152-8551, Japan.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|November 13, 2007
Summary
Faraday waves form on superfluid helium-4 surfaces during vertical vibration. Threshold amplitudes for this instability differ between superfluid and normal fluids due to wall damping.
Area of Science:
- Fluid dynamics
- Quantum fluids
- Superfluidity
Background:
- Faraday waves are standing waves formed by vibrating a fluid's surface.
- Superfluid helium-4 exhibits unique quantum properties, including zero viscosity.
Purpose of the Study:
- To investigate the parametric generation of Faraday waves on the surface of superfluid helium-4.
- To determine the threshold amplitudes for wave formation and compare them to normal fluid behavior.
Main Methods:
- Vertical vibration of a sample cell containing superfluid helium-4.
- Observation and frequency analysis of surface wave patterns.
- Comparison of threshold amplitudes between superfluid and normal fluid states.
Main Results:
- Parametric generation of Faraday waves was observed on the superfluid helium-4 surface.
- Standing-wave patterns emerged with frequencies half the driving frequency.
- Clear threshold vibration amplitudes for instability were identified.
- Differences in thresholds between superfluid and normal fluids were attributed to wall damping.
Conclusions:
- Vertical vibration parametrically generates Faraday waves on superfluid helium-4 surfaces.
- Wall damping significantly influences the threshold amplitude for Faraday wave instability in superfluids.
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