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arXiv · 2408.09137

Mean-field theory of the uniaxial ferroelectric smectic A liquid crystal phase

Aitor Erkoreka·Minjung Huang·Satoshi Aya·Josu Martinez-Perdiguero
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Abstract

Following the groundbreaking discovery of the ferroelectric nematic liquid crystal phase (NF), a series of closely-related new polar phases have also been found. An especially interesting one is the ferroelectric smectic A phase (SmAF) with spontaneous polarization along the layer normal observed in a few materials of the NF realm. Here, we present a mean-field molecular model that successfully captures the rich phase diagrams experimentally observed in the literature in terms of two parameters. Additionally, we carry out second harmonic generation, X-ray diffraction and birefringence measurements in a compound exhibiting the SmAF phase to determine the appropriate order parameters and compare with the model predictions.

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Aitor Erkoreka, Minjung Huang, Satoshi Aya, Josu Martinez-Perdiguero. 2024-08-17. Mean-field theory of the uniaxial ferroelectric smectic A liquid crystal phase. https://doi.org/10.1103/physrevlett.133.208101

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