Landau–de Gennes theory for a −1 boojum in a degenerate hybrid-aligned nematic cell

ABSTRACT

Within Landau–de Gennes theory, the texture of a cylindrically confined degenerate hybrid nematic cell containing a −1 boojum has been investigated using a three-dimensional finite-difference iterative method. We impose strong anchoring conditions, with the nematic director perpendicular to the upper plate and planar degenerate at the lower plate. The director distribution of a degenerate hybrid-aligned nematic cell with a −1 defect is known to have no axial symmetry. The axially symmetric characteristic of the biaxial distribution is surprising. The geometric confinement and boundary condition induce an order reconstruction. The influences of cell thickness on the frustrated cell and eigenvalue exchange solution for a sufficiently small thickness with order reconstruction nucleus have been analysed. Defect rings appear when cell thickness is sufficiently small.

GRAPHICAL ABSTRACT

KEYWORDS:

• −1 Boojum
• Landau−de Gennes theory
• finite-difference iterative
• order reconstruction

Acknowledgements

This research was supported by the National Natural Science Foundation of China under Grant No. 11374087 and the Key Subject Construction Project of Hebei Province University.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [Grant number 11374087].