| Literature DB >> 23690570 |
Ekapop Pairam1, Jayalakshmi Vallamkondu, Vinzenz Koning, Benjamin C van Zuiden, Perry W Ellis, Martin A Bates, Vincenzo Vitelli, Alberto Fernandez-Nieves.
Abstract
We stabilize nematic droplets with handles against surface tension-driven instabilities, using a yield-stress material as outer fluid, and study the complex nematic textures and defect structures that result from the competition between topological constraints and the elasticity of the nematic liquid crystal. We uncover a surprisingly persistent twisted configuration of the nematic director inside the droplets when tangential anchoring is established at their boundaries, which we explain after considering the influence of saddle splay on the elastic free energy. For toroidal droplets, we find that the saddle-splay energy screens the twisting energy, resulting in a spontaneous breaking of mirror symmetry; the chiral twisted state persists for aspect ratios as large as ∼20. For droplets with additional handles, we observe in experiments and computer simulations that there are two additional -1 surface defects per handle; these are located in regions with local saddle geometry to minimize the nematic distortions and hence the corresponding elastic free energy.Keywords: boojum; double twist; geometric frustration; topology; torus
Mesh:
Year: 2013 PMID: 23690570 PMCID: PMC3677424 DOI: 10.1073/pnas.1221380110
Source DB: PubMed Journal: Proc Natl Acad Sci U S A ISSN: 0027-8424 Impact factor: 11.205