Spatially periodic deformations in super-twisted flexoelectric nematic layers

ABSTRACT

Electric field induced deformations in super-twisted layers of nematic liquid crystals possessing flexoelectric properties were investigated numerically. The energetically preferred two-dimensional deformations, taking the form of spatially periodic parallel stripes, were investigated. The twist angles ranging between 120 and 240 degrees were taken into account. Calculations were performed with use of the peculiar elastic properties characteristic for the bent-core nematics. The structures of distorted layers were determined. The results are qualitatively similar to those found in nematic cells twisted by 90 degrees. Two different kinds of periodic deformation were distinguished. They had different structures and different directions with respect to the easy axes corresponding to surface anchoring. The evolution of deformations during changes of bias voltage common for all twist angles was recognised. The role of flexoelectric properties was analysed.

GRAPHICAL ABSTRACT

KEYWORDS:

• Nematics
• flexoelectricity
• director deformations
• periodic patterns
• super-twisted nematic layers
• flexodomains

Disclosure statement

No potential conflict of interest was reported by the author(s).