Abstract
We study the organization of topological defects in a system of nematogens confined to the two-dimensional sphere (). We first perform Monte Carlo simulations of a fluid system of hard rods (spherocylinders) living in the tangent plane of . The sphere is adiabatically compressed until we reach a jammed nematic state with maximum packing density. The nematic state exhibits four disclinations arrayed on a great circle. This arises from the high elastic anisotropy of the system in which splay () is far softer than bending (). We also introduce and study a lattice nematic model on with tunable elastic constants and map out the preferred defect locations as a function of elastic anisotropy. We find a one-parameter family of degenerate ground states in the extreme splay-dominated limit . Thus the global defect geometry is controllable by tuning the relative splay to bend modulus.
- Received 27 December 2007
DOI:https://doi.org/10.1103/PhysRevLett.101.037802
©2008 American Physical Society