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Published on: October 31, 2019
Ring defects in a strongly confined chiral liquid crystal
Jun-ichi Fukuda1, Slobodan Zumer
1Nanosystem Research Institute, National Institute of Advanced Industrial Science and Technology, Umezono, Tsukuba, Japan.
Physical Review Letters
|March 17, 2011
Summary
Stable ring defects form in chiral liquid crystals confined in thin cells. This occurs due to surface anchoring frustrations when cell thickness is 3/4 of the helical pitch.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Liquid Crystal Physics
Background:
- Chiral liquid crystals exhibit complex structures.
- Confining liquid crystals in thin cells with specific surface anchoring can induce novel states.
Purpose of the Study:
- Investigate the stability of ring defects in chiral liquid crystals.
- Explore the role of cell thickness and surface anchoring on defect formation.
Main Methods:
- Numerical simulations were employed.
- Analysis focused on a thin cell with fixed planar anchoring on parallel surfaces.
Main Results:
- A regular array of isolated ring defects was found to be a stable state.
- This stability is achieved when the cell thickness (d) is approximately 3/4 of the helical pitch (p).
- The formation of ring defects is attributed to frustration between helical alignment and surface boundary conditions.
Conclusions:
- Ring defects represent a stable emergent state in confined chiral liquid crystals.
- The specific cell thickness of 3p/4 with parallel anchoring is crucial for this phenomenon.
- Surface-induced frustration drives the formation of these unique defect structures.
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