project title: To Prepare a Report on the Superfluid Kelvin-Helmholz Instability
project leader: Dr. Ladislav Skrbek
access given (in days): 92
access used (in days): 88
local host: Prof. Matti Krusius
home institution: Joint Low Temperature Laboratory, Czech Academy of Sciences, Prague
country of institution: Czech
starting date (yyyy-mm-dd): 2004-04-15
The experiments on the Kelvin-Helmholtz instabity occurring between the superfluid 3HeA and 3HeB have been performed using the ROTA cryostat and reported in PRL89 (2002) No15. Although the basic experimental facts of the underlying physics are suggesting that these experiments can indeed be interpreted in terms of the modified classical Kelvin-Helmholtz instabity, the complete understanding of the problem that includes the two-fluid nature of 3He superfluids and uncertainty in various entering experimental quantities require additional theoretical and experimental work.
Additional experiments in various smooth-walled quartz cells have been performed at various temperatures and pressures in order to increase the accuracy and reliability of the experimental data. From the theoretical point of view, the two-fluid hydrodynamics has been implemented, leading to better agreement between the theory and experiments. Comparison of data at various pressures and temperatures, on the other hand, allowed to improve accuracy in experimental quantities such as magnetization or mutual friction parameters in 3He superfluids. The final report is under preparation.