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Updated: Apr 15, 2026
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Published on: February 27, 2019
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Chiral structures from achiral liquid crystals in cylindrical capillaries
Joonwoo Jeong1, Louis Kang2, Zoey S Davidson2
1Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104; and junoo.benjamin@gmail.com.
Summary
Achiral nematic liquid crystals confined in cylinders form twisted and escaped radial (TER) configurations. These structures exhibit complex defects, including double helices, demonstrating how confinement and material properties drive symmetry breaking.
Area of Science:
- Soft Matter Physics
- Materials Science
- Physical Chemistry
Background:
- Nematic liquid crystals (LCs) exhibit complex behaviors when confined.
- Homeotropic anchoring on cylinder walls influences LC director orientation.
- Elastic anisotropy in LCs can lead to symmetry-breaking phenomena.
Purpose of the Study:
- Investigate chiral symmetry-broken configurations in nematic LCs within cylindrical capillaries.
- Understand how achiral LCs relieve elastic deformations through twist.
- Characterize the resulting twisted and escaped radial (TER) configurations and associated defects.
Main Methods:
- Experimental study using Sunset Yellow FCF, a lyotropic chromonic LC.
- Confined LCs in polymer-coated cylindrical capillaries with homeotropic anchoring.
- Investigation of director configurations using polarized optical microscopy.
- Theoretical explanation and numerical calculations of LC behavior.
Main Results:
- Observed twisted and escaped radial (TER) configurations in achiral nematic LCs.
- Identified diverse topological defects, including domain walls and hedgehog point defects.
- Reported chiral configurations with double helices of disclination lines.
- Demonstrated energetic preference for defects separating opposite twist handedness.
Conclusions:
- Confinement and elastic anisotropy in LCs lead to multiple symmetry breaking.
- The TER configuration and its defects arise from degenerate bend/twist deformations.
- Simple boundary conditions can generate rich defect phenomenology in confined soft materials.
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