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Updated: Sep 9, 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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Geometric frustration in twist-bend nematic droplets
Joseph Pollard1,2, Richard G Morris1,2,3
1School of Physics, UNSW, Sydney, NSW 2052, Australia. joe.pollard@unsw.edu.au.
Soft Matter
|September 2, 2025
Summary
Confinement in spherical droplets creates complex textures in twist-bend nematic liquid crystals. These exotic materials exhibit unique layered states and defect patterns, distinct from chiral counterparts.
Area of Science:
- Materials Science
- Soft Matter Physics
Background:
- Bent-core liquid crystals exhibit a unique twist-bend nematic phase.
- This phase arises from a balance between bend distortion and molecular twist.
- The twist-bend nematic phase shares properties with smectic and cholesteric liquid crystals.
Purpose of the Study:
- To investigate how confinement and boundary anchoring affect the twist-bend nematic phase.
- To catalogue metastable textures in spherical twist-bend nematic droplets.
- To analyze the influence of molecular cone angle and pitch length to droplet radius ratio on these textures.
Main Methods:
- Numerical simulations
- Topological analysis
- Geometric analysis
Main Results:
- Confinement exacerbates frustration in the twist-bend nematic phase.
- Spherical droplets exhibit complex layered states, defect constellations, and Hopfions.
- Observed structures are geometrically distinct from cholesteric phases due to the absence of chirality.
Conclusions:
- Spherical twist-bend nematic droplets display a rich variety of metastable textures under radial anchoring.
- The observed complexity is comparable to cholesteric systems but with unique geometric features.
- This study provides a catalogue of textures relevant for understanding confined liquid crystal systems.
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