Director alignment at the nematic-isotropic interface: elastic anisotropy and active anchoring
Rodrigo C V Coelho1,2, Nuno A M Araújo1,2, Margarida M Telo da Gama1,2
1Centro de Física Teórica e Computacional, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal.
Summary
Active nematic hydrodynamics are typically simplified, but elastic anisotropy influences interfacial alignment. Simulations show active anchoring dominates over elastic effects, except in static systems, altering active length scales.
Area of Science:
- Fluid dynamics
- Soft matter physics
- Active matter
Background:
- Active nematics exhibit interfacial flows and alignment phenomena like active anchoring.
- Current theories often assume elastic isotropy, neglecting real nematic properties.
- Elastic anisotropy in passive nematics can induce its own interfacial anchoring.
Purpose of the Study:
- Investigate the interplay between active anchoring and elastic anisotropy in active nematics.
- Analyze alignment at flat interfaces and in active nematic droplets.
- Determine the conditions under which each anchoring mechanism dominates.
Main Methods:
- Developed multiphase and multicomponent hydrodynamic models for active nematics.
- Incorporated elastic anisotropy into the models.
- Performed simulations for systems with translational invariance and 2D systems.
Main Results:
- Active anchoring is the dominant mechanism, except at very low activity levels where interfaces are static.
- Elastic anisotropy does not influence the dynamics of the system.
- Elastic anisotropy leads to an anisotropic active length.
Conclusions:
- Active anchoring is robust and generally overrides elastic anisotropy effects in active nematics.
- The findings highlight the importance of considering elastic anisotropy for accurate modeling, particularly regarding active length scales.
- This work contributes to understanding complex fluid dynamics in mesoscale systems.
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