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Dissipation of quantum turbulence in the zero temperature limit
P M Walmsley1, A I Golov, H E Hall
1School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom.
Physical Review Letters
|February 1, 2008
Summary
Turbulence in superfluid helium-4 was studied. Researchers found that after an initial spin-down, the vortex line density decays over time, consistent with classical turbulence models.
Area of Science:
- Superfluidity
- Quantum turbulence
- Low-temperature physics
Background:
- Superfluid helium-4 exhibits unique quantum phenomena.
- Understanding turbulence in superfluids is crucial for fundamental physics.
Purpose of the Study:
- To investigate the characteristics of turbulence in superfluid 4He.
- To compare the decay of quantized vortex lines with classical turbulence theories.
Main Methods:
- Impulsive spin-down of a cube-shaped container in superfluid 4He.
- Measurement of quantized vortex line density using negative ion scattering.
- Experiments conducted at temperatures ranging from 0.08 K to 1.6 K.
Main Results:
- Homogeneous turbulence develops approximately 20/Omega after spin-down.
- Vortex line density decays as L ~ t-3/2.
- Energy flux decays as ~ t-3, matching quasiclassical turbulence at high Reynolds numbers.
Conclusions:
- The decay of quantum turbulence in superfluid 4He follows classical turbulence scaling laws.
- A saturated energy-containing length is observed.
- The effective kinematic viscosity at T=0 is determined to be 0.003kappa.
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