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Updated: Aug 4, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Fluctuations of the tensor order-parameter modes in a cholesteric liquid crystal
1Department of Physics and Astronomy, Wayne State University, Detroit, Michigan 48202, USA.
Summary
This study reveals new temperature-dependent fluctuations in cholesteric liquid crystals, including classical director modes and three novel modes near the isotropic phase transition.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Soft Matter Physics
Background:
- Cholesteric liquid crystals exhibit complex behavior governed by their unique helical structure.
- Understanding the order parameter fluctuations is crucial for characterizing phase transitions and material properties.
Purpose of the Study:
- To calculate the fluctuations of the five independent modes of the tensor order parameter in cholesteric liquid crystals.
- To investigate the temperature dependence of these modes, particularly near the transition to the isotropic phase.
Main Methods:
- Utilized a Landau-de Gennes free energy functional.
- Calculated fluctuations of the tensor order parameter modes.
Main Results:
- Identified five independent modes of the tensor order parameter.
- Recovered the classical twist and umbrella director modes in a limiting case.
- Discovered substantial temperature dependence in the umbrella mode.
- Found three additional fluctuation modes near the isotropic phase transition.
Conclusions:
- The classical director model does not fully capture the temperature dependence of cholesteric liquid crystal fluctuations.
- The newly identified modes offer deeper insights into the pre-transitional behavior.
- Experimental detection of some of these modes may have already occurred, warranting further investigation.
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