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Updated: Dec 9, 2025

Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
Gelling and the collective dynamics in ferroelectric liquid crystals
Rachid Meziane1, Martin Brehmer2, Ulrich Maschke1
1Laboratoire de Chimie Macromoléculaire (UMR CNRS No 8009), Bâtiment C6, Université des Sciences et Technologies de Lille, 59655 Villeneuve d'Ascq Cedex, France.
Abstract:
Dielectric spectroscopy has been applied to investigate the dynamic behaviour of a ferroelectric liquid crystal in the smectic C* and smectic A phases confined in gel matrices of a fibre like (1D) or platelet like (2D) structure. These gel matrices were obtained from semicarbazide or bis-acylurea derivatives, which self assemble because of their H-bonding motif. The confinement strongly influences the magnitude of the spontaneous polarization and the collective fluctuations of the director detected as the Goldstone-mode. It is thus possible to detect gelation by dielectric spectroscopy. By this method it was possible to follow the destruction and restoration of the gel structure induced by the photochemical trans-cis isomerisation.
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