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Updated: Jun 22, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Observation of a photo wetting effect on anisotropic liquid-solid interfaces
Guillaume Goubert1, Tigran Galstian
1Department of Physics, Center for Optics, Photonics and Laser, Engineering Physics and Optics Université Laval,Pavillon d'Optique-Photonique, Quebec, Canada.
Optics Express
|June 10, 2009
Summary
Light exposure blocks liquid crystal wetting in a novel anisotropic photo-controlled effect. This phenomenon is driven by light-induced molecular reorientation on surfaces, altering capillary forces.
Area of Science:
- Physics
- Materials Science
Background:
- Capillary action drives fluid movement in confined spaces.
- Nematic liquid crystals exhibit unique optical and orientational properties.
Purpose of the Study:
- To experimentally observe and explain anisotropic photo-controlled wetting.
- To investigate the mechanism of light-induced blocking of liquid crystal propagation.
Main Methods:
- Experimental observation of capillary propagation in a "sandwich" cell.
- Analysis of light-induced molecular reorientation on solid surfaces.
- Theoretical postulation of the underlying physical mechanism.
Main Results:
- Anisotropic photo-controlled wetting effect was observed.
- Light exposure was found to block capillary propagation of nematic liquid crystals.
- Optical reorientation of surface molecules was identified as the key factor.
Conclusions:
- The study demonstrates a novel method for controlling wetting using light.
- Light-induced surface molecular reorientation effectively modulates capillary forces.
- This finding has potential implications for microfluidics and display technologies.
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