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Alignment transition in a nematic liquid crystal due to field-induced breaking of anchoring

Valentina S. U. Fazio·Lachezar Komitov
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Abstract

We report on the alignment transition of a nematic liquid crystal from initially homeotropic to quasi-planar due to field-induced anchoring breaking. The initial homeotropic alignment is achieved by Langmuir-Blodgett monolayers. In this geometry the anchoring strength can be evaluated by the Frederiks transition technique. Applying an electric field above a certain threshold provokes turbulent states denoted DSM1 and DSM2. While DSM1 does not affect the anchoring, DSM2 breaks the coupling between the surface and the liquid crystal: switching off the field from a DSM2 state does not immediately restore the homeotropic alignment. Instead, we obtain a quasi-planar metastable alignment. The cell thickness dependence for the transition is related to the

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Valentina S. U. Fazio, Lachezar Komitov. 1999-02-18. Alignment transition in a nematic liquid crystal due to field-induced breaking of anchoring. https://doi.org/10.1209/epl%2Fi1999-00559-8

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