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Updated: May 8, 2026
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High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Knots and nonorientable surfaces in chiral nematics.
Thomas Machon1, Gareth P Alexander
1Department of Physics and Centre for Complexity Science, University of Warwick, Coventry CV4 7AL, United Kingdom.
Summary
Researchers explored topological phenomena using liquid crystals and colloids. They demonstrated constructing torus knots and links around Möbius strips, advancing the understanding of knotted fields in materials science.
Area of Science:
- Topological physics and materials science
- Liquid crystal physics and colloid science
Background:
- Knotted fields are fundamental in diverse physical systems, from DNA to fluid dynamics.
- Liquid crystals offer a controllable platform for studying topological defects and knot configurations.
- Previous work utilized spherical and toroidal colloids to create defects in liquid crystals for photonic applications.
Purpose of the Study:
- To explore the topological implications of using nonorientable surfaces as colloids in liquid crystals.
- To construct specific types of torus knots and links (p,2) around Möbius strips within liquid crystal systems.
Main Methods:
- Utilizing colloids shaped as nonorientable surfaces (Möbius strips).
- Investigating the topological properties and defect structures formed in liquid crystals around these colloids.
- Constructing and analyzing torus knots and links of type (p,2).
Main Results:
- Demonstrated the successful construction of torus knots and links around multiply twisted Möbius strips in liquid crystals.
- Revealed the full topological implications of employing nonorientable surfaces in colloidal liquid crystal systems.
- Established a method for creating complex knotted configurations using nonorientable colloids.
Conclusions:
- Nonorientable colloids provide a novel route to generating complex topological structures in liquid crystals.
- This research expands the toolkit for exploring topological phenomena in soft matter.
- The findings hold potential for developing new photonic devices based on engineered topological defects.
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