Numerical investigation of liquid crystal colloids using a continuum description

Area of Science:

• Soft Matter Physics
• Materials Science
• Continuum Mechanics

Background:

• Nematic liquid crystals exhibit complex orientational order.
• Interactions between liquid crystals and confining geometries are crucial for device applications.
• Understanding topological defects is key to liquid crystal physics.

Purpose of the Study:

• To numerically investigate the configuration of nematic liquid crystals around two spherical particles.
• To explore phenomena like capillary condensation and defect formation.
• To analyze the impact of particle proximity on liquid crystal orientation.

Main Methods:

• Landau-de Gennes continuum theory using a second-rank tensor order parameter Q(ij).
• Bispherical coordinates to model the two-particle geometry.
• Adaptive mesh refinement for high-resolution simulation of topological defects.

Main Results:

• Observed capillary condensation of the nematic liquid crystal between the two particles near the nematic-isotropic transition point.
• Identified the formation of a hyperbolic hedgehog defect near a particle under strong normal anchoring below the transition point.
• Demonstrated significant distortion of the nematic orientation profile when particles are in close proximity.

Conclusions:

• The study reveals key phenomena in confined nematic liquid crystals, including condensation and defect formation.
• Numerical simulations provide insights into the influence of particle geometry and anchoring on liquid crystal order.
• Findings contribute to the understanding of liquid crystal behavior in complex environments.