Uniaxial versus biaxial character of nematic equilibria in three dimensions

Henao, Duvan and Majumdar, Apala and Pisante, Adriano (2017) Uniaxial versus biaxial character of nematic equilibria in three dimensions. Calculus of Variations and Partial Differential Equations, 56. 55. ISSN 1432-0835 (https://doi.org/10.1007/s00526-017-1142-8)

[thumbnail of Henao-etal-CVPDE-2017-Uniaxial-versus-biaxial-character-of-nematic-equilibria-in-three-dimensions]
Preview
Text. Filename: Henao_etal_CVPDE_2017_Uniaxial_versus_biaxial_character_of_nematic_equilibria_in_three_dimensions.pdf
Final Published Version
License: Creative Commons Attribution 4.0 logo

Download (635kB)| Preview

Abstract

We study global minimizers of the Landau–de Gennes (LdG) energy functional for nematic liquid crystals, on arbitrary three-dimensional simply connected geometries with topologically non-trivial and physically relevant Dirichlet boundary conditions. Our results are specific to an asymptotic limit coined in terms of a dimensionless temperature and material-dependent parameter, t and some constraints on the material parameters, and we work in the t→∞ limit that captures features of the widely used Lyuksyutov constraint (Kralj and Virga in J Phys A 34:829–838, 2001). We prove (i) that (re-scaled) global LdG minimizers converge uniformly to a (minimizing) limiting harmonic map, away from the singular set of the limiting map; (ii) we have points of maximal biaxiality and uniaxiality near each singular point of the limiting map; (iii) estimates for the size of “strongly biaxial” regions in terms of the parameter t. We further show that global LdG minimizers in the restricted class of uniaxial Q-tensors cannot be stable critical points of the LdG energy in this limit.