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Defect coalescence in spherical nematic shells
Teresa Lopez-Leon1, Martin A Bates, Alberto Fernandez-Nieves
1School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
Summary
Topological defects in nematic liquid crystals within spherical shells coalesce into pairs. This process forms two single defects, influenced by shell geometry and thickness variations.
Area of Science:
- Physics
- Materials Science
Background:
- Nematic liquid crystals exhibit topological defects due to geometric constraints.
- Spherical confinement introduces specific topological defect configurations.
Purpose of the Study:
- To investigate the coalescence of topological defects in spherical nematic liquid crystals.
- To understand the role of surface anchoring and shell geometry in defect dynamics.
Main Methods:
- Experimental observation of defect behavior.
- Computational simulations of liquid crystal hydrodynamics.
Main Results:
- Four s=+1/2 defects coalesce into two s=+1 defects upon changing surface anchoring.
- Coalescence speed is maximized when defects are antipodal, linked to shell thickness inhomogeneity.
Conclusions:
- Surface orientation change drives defect pair coalescence in confined nematics.
- Shell thickness variations significantly impact defect dynamics and coalescence rates.
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