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Treating Surfaces with a Cold Atmospheric Pressure Plasma using the COST-Jet
Published on: November 2, 2020
Casimir forces, surface fluctuations, and thinning of superfluid film
Roya Zandi1, Joseph Rudnick, Mehran Kardar
1Department of Chemistry and Biochemistry, UCLA, Box 951569, Los Angeles, California 90095-1569, USA.
Abstract:
Recent experiments on the wetting of 4He have shown that the film becomes thinner at the lambda transition and in the superfluid phase. The difference in thickness above and below the transition has been attributed to a Casimir interaction which is a consequence of a broken continuous symmetry in the bulk superfluid. However, the observed thinning of the film is larger than can be accounted by this Casimir force. We show that surface fluctuations give rise to an additional force, similar in form but larger in magnitude, which may explain the observations.
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