Optimized frequency regime for the electrohydrodynamic induction of a uniformly lying helix structure

Yu Lin Nian, Po Chang Wu, Wei Lee*

*Corresponding author for this work

Research output: Contribution to journalArticle

8 Scopus citations

Abstract

This study specifies the optimal frequency regime for the uniformly lying helix (ULH) alignment induced by the electrohydrodynamic (EHD) effect in a cholesteric liquid crystal with positive dielectric anisotropy. Based on the transport behavior of ionic charges in response to the externally applied ac electric field, four frequency regimes, divided by three critical frequencies (i.e., fL, fR, and fH), are identified by means of dielectric spectroscopy. By discussing the voltage-dependent cholesteric textural changes in each frequency regime in terms of the voltageand frequency-dependent transmission spectra and optical textures, our results suggest that the designated frequency regime fL, <f < fR, where electrical charges can effectively oscillate in the bulk of the cell with less ion accumulation on the electrode surfaces, is most adequate for the generation of well-structured ULH via effective induction of the EHD flow by the external voltage. As a result, this study provides a pathway to determination of the optimal frequency regime for generating the EHD-induced ULH state prior to voltage treatment.

Original languageEnglish
Pages (from-to)227-232
Number of pages6
JournalPhotonics Research
Volume4
Issue number6
DOIs
StatePublished - 1 Dec 2016

Fingerprint Dive into the research topics of 'Optimized frequency regime for the electrohydrodynamic induction of a uniformly lying helix structure'. Together they form a unique fingerprint.

  • Cite this