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Updated: Sep 30, 2025

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Heliconical-fluctuation-induced compensation point in the diluted cholesteric phase of mixtures containing the
Patrick Oswald1, Alain Dequidt2
1Université Lyon, ENS de Lyon, Université Claude Bernard, CNRS, Laboratoire de Physique, F-69342 Lyon, France.
Abstract:
We show experimentally and theoretically that the heliconical fluctuations that develop in a cholesteric phase (Ch) close to a transition to a chiral twist-bend nematic phase (N_{TB}) may lead to the appearance of a compensation point. At this point, the equilibrium twist of the cholesteric phase vanishes and changes sign. Mixtures of the flexible dimer CB7CB and the rodlike molecules 8CB or 5CB, doped with a small amount of the chiral molecules R811, S2011, CC, or CB15, are used in experiments to determine the conditions for the appearance of a compensation point.
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