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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Pseudo-casimir structural force drives spinodal dewetting in nematic liquid crystals
1J. Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia and and Department of Physics, University of Ljubljana, Jadranska 19, SI-1000 Ljubljana, Slovenia.
Physical Review Letters
|October 4, 2000
Summary
We theoretically analyzed fluctuation-induced forces in nematic liquid crystal films. The force is attractive at small distances and repulsive at larger distances, explaining spinodal dewetting experiments.
Area of Science:
- Physics
- Materials Science
- Physical Chemistry
Background:
- Thin films exhibit unique physical phenomena due to surface interactions.
- Liquid crystals possess anisotropic properties crucial for display technologies.
- Competing surface interactions can lead to complex interfacial behaviors.
Purpose of the Study:
- To theoretically investigate the fluctuation-induced force in thin nematic films.
- To analyze the impact of competing surface interactions on this force.
- To provide a theoretical framework for interpreting experimental observations of dewetting.
Main Methods:
- Theoretical analysis of fluctuation-induced forces.
- Modeling of competing surface interactions in thin nematic films.
- Comparison with experimental data on spinodal dewetting.
Main Results:
- The fluctuation-induced force is attractive at short distances.
- The force becomes repulsive at larger separation distances.
- The theoretical findings consistently explain spinodal dewetting of 5CB on silicon.
Conclusions:
- The study elucidates the distance-dependent nature of fluctuation-induced forces in nematic films.
- The findings offer a consistent interpretation of experimental spinodal dewetting.
- This work identifies the observed phenomenon as the first experimental evidence of the pseudo-Casimir effect in liquid crystals.
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