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Polymer-Dispersed Cholesteric Liquid Crystal under Homeotropic Anchoring: Electrically Induced Structures with
Anna P Gardymova1,2, Mikhail N Krakhalev1,2, Vladimir Yu Rudyak3
1Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Krasnoyarsk 660036, Russia.
Polymers
|April 12, 2022
Summary
This study explores polymer-dispersed cholesteric liquid crystals, revealing how electric fields reconfigure their orientational structures. New topological states, including λ+1/2-disclination, were identified and characterized, paving the way for advanced optical materials.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Polymer Science
Background:
- Cholesteric liquid crystals exhibit complex orientational structures.
- Polymer-dispersed liquid crystals (PDLCs) offer unique electro-optical properties.
- Homeotropic anchoring influences liquid crystal droplet behavior.
Purpose of the Study:
- To investigate the orientational structures of polymer-dispersed cholesteric liquid crystals under homeotropic anchoring.
- To demonstrate and analyze the transformations of these structures under electric fields.
- To identify and characterize novel topological states within these systems.
Main Methods:
- Experimental observation of liquid crystal droplet behavior.
- Theoretical modeling of orientational structures and transformations.
- Analysis of topological defects, such as disclinations.
Main Results:
- Demonstrated switching of cholesteric droplets between different topological states.
- Identified and analyzed structures with λ+1/2-disclination formed from twisted toroidal configurations.
- Detailed investigation of structural transformations from bipolar to toroidal and then to λ+1/2-disclination states under varying electric fields.
- Observed the appearance of λ−1/2-disclination structures.
Conclusions:
- The study provides a comprehensive understanding of electro-optical switching in polymer-dispersed cholesteric liquid crystals.
- The identified topological structures and their field-induced transformations are crucial for designing novel optical materials.
- These findings hold promise for developing optical materials with tunable and programmable properties.
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