The transition from surface to bulk normal dielectric rolls in a nematic liquid crystal is imaged by fluorescence confocal polarizing microscopy. The three-dimensional director structure and the liquid flow are scanned in both the layer plane and the transverse plane. Two systems of small-scale convective flow are formed, one at each electrode. Strong anchoring makes director oscillations difficult and charges accumulate by the Carr-Helfrich mechanism. The middle region is a structureless convection where the director oscillates with the frequency of the applied voltage. The small-scale flow eventually fills the cell from one electrode to the other as one system of thin and elongated rolls. The true dielectric mode is not a director pattern, rather a surface flow instability.
Physical Review E
Copyright 2006 American Physical Society. Available on publisher's site at http://dx.doi.org/10.1103/PhysRevE.74.041702
Gheorghiu, Nadina; Smalyukh, Ivan I.; Lavrentovich, Oleg; Gleeson, Jim T. (2006). Three-Dimensional Imaging of Dielectric Patterns in Electrohydrodynamic Convection of a Nematic Liquid Crystal. Physical Review E 74(4) doi: 10.1103/PhysRevE.74.041702. Retrieved from https://oaks.kent.edu/cpippubs/203