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Updated: May 28, 2025
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High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
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Evolution of Focal Conic Domains in SmA-N Phase Transition
Vincent Plée1, Jordan Lacam1, Gianni Pascoli1
1Laboratoire Physique des Systèmes Complexes, Université de Picardie Jules Verne, 33 rue Saint-Leu, 80039 Amiens, France.
Materials (Basel, Switzerland)
|February 13, 2025
Summary
Focal conic domains in liquid crystals change shape during phase transitions. Researchers observed and modeled this evolution, identifying a coefficient behaving like a critical exponent.
Area of Science:
- Soft matter physics
- Liquid crystal science
- Geometric phase transitions
Background:
- Focal conics are characteristic geometric structures in liquid crystal phases with periodicity, such as smectic and cholesteric phases.
- Focal conic domains (FCDs) are specifically studied in the context of smectic A liquid crystals.
- These domains undergo transformations during phase transitions, notably from smectic A to nematic phases.
Purpose of the Study:
- To experimentally observe and analyze the evolution of focal conic domains (FCDs) in smectic A liquid crystals during the transition to a nematic phase.
- To develop a modeling approach for a precise description of FCD evolution.
- To identify key parameters, such as critical exponents, governing this phenomenon.
Main Methods:
- Experimental observation of FCDs in liquid crystals undergoing phase transition.
- Development of a mathematical model to simulate and describe FCD behavior.
- Analysis of FCD eccentricity changes and their disappearance during the smectic A to nematic transition.
Main Results:
- Detailed experimental observations of FCD evolution, including increasing eccentricity.
- A precise mathematical model accurately describing the observed FCD transformations.
- Identification of a coefficient exhibiting critical exponent-like behavior during the phase transition.
Conclusions:
- The study provides a comprehensive understanding of focal conic domain evolution during liquid crystal phase transitions.
- The developed model offers a precise quantitative description of this geometric phenomenon.
- The discovery of a critical exponent-like coefficient opens avenues for further theoretical and experimental research in liquid crystal physics.
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