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Updated: Jul 11, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Critical Casimir effect in superfluid wetting films.
A Maciołek1, A Gambassi, S Dietrich
1Max-Planck-Institut für Metallforschung, Heisenbergstrasse 3, D-70569 Stuttgart, Germany.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|October 13, 2007
Summary
Critical Casimir forces influence helium film thickness near phase transitions. Calculations explain experimental data for pure helium-4 and helium-3/helium-4 mixtures, predicting crossover behavior and logarithmic corrections.
Area of Science:
- Physics
- Thermodynamics
- Surface Science
Background:
- Experimental data reveal changes in helium film thickness near thermodynamic phase transitions.
- These changes are linked to critical Casimir forces, especially for pure helium-4 at the lambda transition and helium-3/helium-4 mixtures at the tricritical point.
Purpose of the Study:
- To calculate scaling functions for critical Casimir forces.
- To understand the behavior of these forces in helium-4 and helium-3/helium-4 mixtures.
- To predict the crossover behavior between the tricritical point and the lambda transition.
Main Methods:
- Modeling universality classes relevant to the phase transitions.
- Calculating scaling functions for critical Casimir forces.
- Analyzing experimental data for film thickness changes.
Main Results:
- The study explains the observed rich behavior of scaling functions for helium mixtures.
- A pronounced maximum in critical Casimir forces below the tricritical point is explained by a "soft-mode" phase.
- Logarithmic corrections to scaling functions near the tricritical point were identified.
Conclusions:
- The critical Casimir forces play a significant role in the wetting behavior of helium films near phase transitions.
- The theoretical models successfully explain experimental observations and predict new phenomena.
- Understanding these forces is crucial for comprehending critical phenomena in condensed matter systems.
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