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arXiv · 2507.08754

Interplay of polar order and positional order in liquid crystals -- observation of re-entrant ferroelectric nematic phase

Grant Strachan·Shona Ramsay·Marijus Juodka·Damian Pociecha·Jadwiga Szydlowska·John M. D. Storey·Natasa Vaupotic·Rebecca Walker·Ewa Gorecka
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Abstract

We show that development of polar order may spontaneously destroy the lamellar structure of a liquid crystal. This results in an unusual sequence of phases with the ferroelectric nematic phase appearing below a non-polar smectic phase. The effect is related to unfavourable dipole interactions within the smectic layers and can be explained by Landau theory in which the temperature dependent term is non-monotonic as it is renormalized by spontaneous electric polarization.

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Grant Strachan, Shona Ramsay, Marijus Juodka, Damian Pociecha, Jadwiga Szydlowska, John M. D. Storey, Natasa Vaupotic, Rebecca Walker, Ewa Gorecka. 2025-07-11. Interplay of polar order and positional order in liquid crystals -- observation of re-entrant ferroelectric nematic phase. https://arxiv.org/abs/2507.08754

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