Properties of surface Landau-de Gennes Q-tensor models

Area of Science:

• Physics
• Materials Science
• Soft Matter Physics

Background:

• Uniaxial nematic liquid crystals exhibit complex behavior when subjected to tangential anchoring on curved surfaces.
• This interaction involves a interplay between surface geometry, topology, and molecular orientation.
• Existing models for liquid crystal surface anchoring have limitations.

Purpose of the Study:

• To develop and analyze a general thin film limit of the Landau-de Gennes Q-tensor model for liquid crystals on curved surfaces.
• To compare fundamental properties of this generalized model with previously proposed surface models.
• To suggest experimental methods for distinguishing between different model assumptions.

Main Methods:

• Utilizing a Landau-de Gennes Q-tensor model in a thin film limit, retaining 3D model characteristics.
• Analyzing the alignment of orientational degrees of freedom with principal curvature lines.
• Investigating order parameter symmetry and phase transition types.

Main Results:

• The generalized thin film model encompasses previously proposed surface models as special cases.
• Key differences in alignment, symmetry, and phase transitions between models were identified.
• The study provides a framework for understanding liquid crystal behavior on curved substrates.

Conclusions:

• The developed Landau-de Gennes Q-tensor model offers a comprehensive approach to liquid crystals on curved surfaces.
• Experimental validation is crucial for selecting appropriate models for specific applications.
• This research advances the understanding of liquid crystal-surface interactions.