Reorientational dynamics of conjugated nematic point defects

Abstract

To appreciate the universal qualitative features of defect annihilation in nematic liquid crystals, we study how the viscous force of reorientational dynamics behaves under a transformation that reverses the sign of the defect's topological charge. As an illustration of our general results, we consider a class of point defects that were first studied by A. Saupe. The reorientational viscous forces acting on them differ dramatically from those acting on line defects.

Keywords:

• liquid crystals
• defect dynamics
• parity

Notes

1. Half-integer values of s are allowed in Equation (28)(28), but they do not lead to point defects. Indeed, changing ϕ by π leaves n invariant in Equation (21)(21) for the defect-free homogeneous director field ϑ ≡ 0, and it leads to − n when , which gives line defects.