Electric-field-induced nematic-cholesteric transition and 3-D director structures in homeotropic cells

I. I. Smalyukh; B. I. Senyuk; P. Palffy-Muhoray; O. D. Lavrentovich; H. Huang; E. C. Gartland, Jr.; V. H. Bodnar; T. Kosa; B. Taheri

doi:10.1103/physreve.72.061707

arXiv · cond-mat/0512365

Electric-field-induced nematic-cholesteric transition and 3-D director structures in homeotropic cells

I. I. Smalyukh·B. I. Senyuk·P. Palffy-Muhoray·O. D. Lavrentovich·H. Huang·E. C. Gartland, Jr.·V. H. Bodnar·T. Kosa·B. Taheri

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Abstract

We study the phase diagram of director structures in cholesteric liquid crystals of negative dielectric anisotropy in homeotropic cells of thickness d which is smaller than the cholesteric pitch p. The basic control parameters are the frustration ratio d/p and the applied voltage U. Fluorescence Confocal Polarising Microscopy allows us to directly and unambiguously determine the 3-D director structures. The results are of importance for potential applications of the cholesteric structures, such as switchable gratings and eyewear with tunable transparency based.

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I. I. Smalyukh, B. I. Senyuk, P. Palffy-Muhoray, O. D. Lavrentovich, H. Huang, E. C. Gartland, Jr., V. H. Bodnar, T. Kosa, B. Taheri. 2005-12-16. Electric-field-induced nematic-cholesteric transition and 3-D director structures in homeotropic cells. https://doi.org/10.1103/physreve.72.061707

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