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Re-entrant ferroelectricity in liquid crystals

D. Pociecha·E. Gorecka·M. Cepic·N. Vaupotic·B. Zeks·D. Kardas·J. Mieczkowski
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Abstract

The ferroelectric (Sm C$^*$) -- antiferroelectric (Sm C$^*_A$) -- reentrant ferroelectric (re Sm C$^*$) phase temperature sequence was observed for system with competing synclinic - anticlinic interactions. The basic properties of this system are as follows (1) the Sm C$^*$ phase is metastable in temperature range of the Sm C$^*_A$ stability (2) the double inversions of the helix handedness at Sm C$^*$ -- Sm C$^*_A$ and Sm C$^*_A$% -- re-Sm C$^*$ phase transitions were found (3) the threshold electric field that is necessary to induce synclinic ordering in the Sm C$^*_A$ phase decreases near both Sm C$^*_A$ -- Sm C$^*$ and Sm C$^*_A$ -- re-Sm C$^*$ phase boundaries, and it has maximum in the middle of the Sm C$^*_A$ stability region. All these properties are properly described by simple Landau model that accounts for nearest neighboring layer steric interactions and quadrupolar ordering only.

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D. Pociecha, E. Gorecka, M. Cepic, N. Vaupotic, B. Zeks, D. Kardas, J. Mieczkowski. 2000-11-02. Re-entrant ferroelectricity in liquid crystals. https://doi.org/10.1103/physrevlett.86.3048

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