Intermittent Switching between Potential Flow and Turbulence in Superfluid Helium at mK Temperatures
Condensed Matter
2007-05-23 v1 Chaotic Dynamics
Fluid Dynamics
Abstract
Superfluid flow around an oscillating microsphere is investigated at temperatures down to 25 mK. Stable laminar flow below a critical velocity and turbulence at large drives are found to be separated below 0.5 K by an intermediate range of driving forces where the flow is unstable, intermittently switching between laminar and turbulent phases. We have recorded time series of this switching phenomenon and have made a statistical analysis of the switching probability. The mean lifetime of the turbulent phases grows with increasing drive and becomes infinite at a critical value. Stability of the laminar phases above the critical velocity is limited by natural background radioactivity or cosmic rays.
Cite
@article{arxiv.cond-mat/0009299,
title = {Intermittent Switching between Potential Flow and Turbulence in Superfluid Helium at mK Temperatures},
author = {Michael Niemetz and Hubert Kerscher and Wilfried Schoepe},
journal= {arXiv preprint arXiv:cond-mat/0009299},
year = {2007}
}
Comments
4 pages, 5 figures