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Updated: Mar 13, 2026
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Forming, Confining, and Observing Microtubule-Based Active Nematics
Published on: January 13, 2023
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Mesoscale structure of chiral nematic shells.
Ye Zhou1, Ashley Guo1, Rui Zhang1
1Institute for Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, USA. depablo@uchicago.edu.
Soft Matter
|October 11, 2016
Summary
Chiral nematic shells exhibit structural transitions that alter defect positions, suggesting their use as sensors. Varying chirality and thickness reveals distinct equilibrium states in these liquid crystal systems.
Area of Science:
- Soft Matter Physics
- Materials Science
- Liquid Crystal Physics
Background:
- Topological defects in nematic liquid crystals (LCs) are crucial for applications.
- Confinement in shell geometries offers a method to control these defects.
- Chiral nematic materials introduce unique properties to LC systems.
Purpose of the Study:
- To explore nematic order frustration in chiral shell geometries using Landau-de Gennes formalism.
- To construct a phase diagram for uniform shells by varying chirality and thickness.
- To investigate the impact of thickness heterogeneity on defect positioning.
Main Methods:
- Landau-de Gennes formalism applied to chiral nematic shells.
- Systematic variation of shell chirality and thickness.
- Analysis of structural transitions and defect positioning.
Main Results:
- A phase diagram for uniform shells was constructed, including tetravalent, bipolar (BS), bent, and radial spherical structures (RSS).
- The transition from BS to RSS structures, influenced by chirality and shell geometry, showed abrupt changes in defect positions.
- Thickness heterogeneity in shells led to distinct equilibrium positions for the inner core, governed by shell chirality.
Conclusions:
- Chiral nematic shells exhibit structural transitions sensitive to chirality and geometry, with potential applications as sensors due to predictable defect repositioning.
- Shell chirality significantly influences the equilibrium positions of inner cores in heterogeneous shells.
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