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Updated: May 8, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Confined nematic liquid crystal between two spherical boundaries with planar anchoring
Seyed Reza Seyednejad1, Mohammad Reza Mozaffari, Mohammad Reza Ejtehadi
1Department of Physics, Sharif University of Technology, P.O. Box 11155-9161, Tehran, Iran.
Summary
Defect structures in microscale nematic liquid crystal shells are crucial for electro-optical applications. Shell thickness and asymmetry control defect types, influencing inner droplet stability and device performance.
Area of Science:
- Physics
- Materials Science
Background:
- Nematic shells of liquid crystals are microscale colloidal objects.
- Defect structures within these shells are critical for electro-optical applications.
Purpose of the Study:
- To numerically minimize the free energy of symmetric and asymmetric spherical nematic liquid crystal shells.
- To investigate the influence of shell thickness and asymmetry on defect structures and inner droplet stability.
Main Methods:
- Numerical free energy minimization.
- Analysis of degenerate planar anchoring and isotropic nematic elasticity.
- Control of shell thickness and asymmetry.
Main Results:
- Symmetric shells exhibit boojum defects in thick shells and tetrahedral defects in thin shells.
- Asymmetric shells show boojum defects transforming to trigonal configurations, leading to off-center inner droplet positions.
- Thin asymmetric shells display two degenerate director textures, affecting inner droplet stability.
Conclusions:
- Shell thickness and asymmetry are key parameters for controlling defect structures in nematic liquid crystal shells.
- Defect configurations significantly impact the stability and positioning of the inner droplet.
- Understanding these relationships is vital for designing advanced electro-optical devices.
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