Threshold voltages and optical retardation of deformed flexoelectric nematic layers with asymmetric surface anchoring

G. Derfel, M. Buczkowska

Research output: Contribution to journalArticlepeer-review

1 Scopus citations

Abstract

Deformations of homeotropically aligned flexoelectric nematic layers induced by dc electric fields were simulated numerically. Two different anchoring strengths on the limiting surfaces were assumed. Nematic material was characterised by negative dielectric anisotropy. Both signs of the sum of flexoelectric coefficients were taken into account. The electric properties of the layer were described in terms of a weak electrolyte model. Mobility of cations was assumed to be one order of magnitude lower than that of anions. Quasi-blocking electrode contacts were assumed. The threshold voltages for deformations were determined by means of calculations of the phase difference Φ between ordinary and extraordinary light rays passing through a layer placed between crossed polarisers. The threshold values depended on the polarity of the bias voltage U. When the threshold value was exceeded, the phase difference increased with the voltage. Two different Φ(U/Uthreshold) dependencies for the two polarities of the voltage were found for each layer if the nematic possessed the flexoelectric properties. The possibility of using this effect to detect the flexoelectricity in the nematic was explored by simulated experiments. The effectiveness of the proposed method is discussed.

Original languageEnglish
Pages (from-to)205-209
Number of pages5
JournalOpto-electronics Review
Volume21
Issue number2
DOIs
StatePublished - 1 Jan 2013
Externally publishedYes

Keywords

  • director deformations
  • flexoelectricity
  • nematics
  • optical retardation
  • surface anchoring

Fingerprint

Dive into the research topics of 'Threshold voltages and optical retardation of deformed flexoelectric nematic layers with asymmetric surface anchoring'. Together they form a unique fingerprint.

Cite this