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Updated: Jun 3, 2026
06:24
High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Shape selection of twist-nematic-elastomer ribbons.
Yoshiki Sawa1, Fangfu Ye, Kenji Urayama
1Department of Material Chemistry, Kyoto University, Kyoto 615-8510, Japan.
Summary
Microscopic chirality in liquid crystal films creates macroscopic chiral shapes like helicoids and ribbons. Researchers controlled these shapes and ribbon pitch using temperature, advancing chiral material design.
Area of Science:
- Materials Science
- Soft Matter Physics
- Chirality Studies
Background:
- Understanding how microscopic chirality dictates macroscopic form is crucial for biomaterials and supramolecular systems.
- Chiral shape formation in materials like liquid crystal elastomers is an active area of research.
Purpose of the Study:
- To investigate the physical mechanisms by which chiral arrangements in liquid crystal films induce macroscopic chiral structures.
- To explore the tunability of these structures, specifically the pitch of spiral ribbons, through external stimuli.
Main Methods:
- Experimental investigation of twist-nematic-elastomer films with chiral mesogen arrangements.
- Theoretical modeling to understand the coupling between liquid crystalline order and elasticity.
- Temperature variation as a method to control the pitch of formed spiral ribbons.
Main Results:
- Demonstrated that chiral mesogen arrangement in elastomer films leads to the formation of helicoids and spiral ribbons.
- Established a link between microscopic chiral order and macroscopic shape formation.
- Showed that the pitch of spiral ribbons can be precisely tuned by temperature.
Conclusions:
- The coupling between liquid crystalline order and elasticity is key to macroscopic chiral shape formation from microscopic chirality.
- Temperature offers a viable method for controlling the pitch of chiral ribbons in these materials.
- Findings provide insights into the physics of chiral material self-assembly and design principles for new chiral structures.
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