Visualising the crossover between 3D and 2D topological defects in nematic liquid crystals. Issue 13 (8th December 2018)

• Record Type: Journal Article
• Authors: Afghah, Sajedeh; Selinger, Robin L. B.; Selinger, Jonathan V.
• Is Part Of: Liquid crystals. Volume 45:Issue 13/15(2018)
• Page Start: 2022
• Page End: 2032
• Publication Date: 2018-12-08
• Subjects: Nematic liquid crystals -- topological defects -- disclinations -- negative dielectric anisotropy; Liquid crystals -- Periodicals; 548.905
• DOI: 10.1080/02678292.2018.1494857
• Languages: English
• ISSNs: 0267-8292

Abstract

ABSTRACT: The topological properties of disclinations are quite different for liquid crystals in two dimensions (2D) or three dimensions (3D). In 2D, there are distinct types of disclinations with topological charges or winding numbers of any half-integer or integer. By contrast, in 3D, all half-integer disclinations are topologically equivalent to each other, and integer disclinations are not defects at all. In this study, we use numerical simulations to explore the crossover between 3D and 2D. We show that certain disclination lines between patterned surfaces can exist when the director field is free to rotate in 3D, but not when the director field is forced into the 2D plane (by an electric field applied to a liquid crystal with negative dielectric anisotropy). As a result, these disclinations are expelled from the liquid crystal. GRAPHICAL ABSTRACT: