Ferroelectric-Ferroelastic Phase Transition in a Nematic Liquid Crystal.
Nerea Sebastián,Luka Cmok,Richard J. Mandle,Maria de la Fuente,Irena Drevenšek Olenik,Irena Drevenšek Olenik,Martin Čopič,Martin Čopič,Alenka Mertelj +8 more
TLDR
It is shown that ferroelectric ordering of the molecules causes the formation of recently reported splay nematic liquid-crystalline phase, which drives an orientational ferroelastic transition via flexoelectric coupling.Abstract:
Ferroelectric ordering in liquids is a fundamental question of physics. Here, we show that ferroelectric ordering of the molecules causes the formation of recently reported splay nematic liquid-crystalline phase. As shown by dielectric spectroscopy, the transition between the uniaxial and the splay nematic phase has the characteristics of a ferroelectric phase transition, which drives an orientational ferroelastic transition via flexoelectric coupling. The polarity of the splay phase was proven by second harmonic generation imaging, which additionally allowed for determination of the splay modulation period to be of the order of 5-10 microns, also confirmed by polarized optical microscopy. The observations can be quantitatively described by a Landau-de Gennes type of macroscopic theory.read more
Citations
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First-principles experimental demonstration of ferroelectricity in a thermotropic nematic liquid crystal: Polar domains and striking electro-optics.
Xi Chen,Eva Korblova,Dengpan Dong,Dengpan Dong,Xiaoyu Wei,Xiaoyu Wei,Renfan Shao,Leo Radzihovsky,Matthew A. Glaser,Joseph E. Maclennan,Dmitry Bedrov,Dmitry Bedrov,David M. Walba,Noel A. Clark +13 more
TL;DR: The experimental determination of the structure and response to applied electric field of the lower-temperature nematic phase of the previously reported calamitic compound 4-[(4-nitrophenoxy)carbonyl]phenyl2,4-dimethoxybenzoate and results indicate a significant potential for transformative, new nematic physics, chemistry, and applications based on the enhanced understanding, development, and exploitation of molecular electrostatic interaction.
Journal ArticleDOI
Development of ferroelectric nematic fluids with giant-ε dielectricity and nonlinear optical properties.
Jinxing Li,Hiroya Nishikawa,Junichi Kougo,Junchen Zhou,Shuqi Dai,Wentao Tang,Xiuhu Zhao,Yuki Hisai,Mingjun Huang,Satoshi Aya +9 more
TL;DR: In this paper, small molecules with high polarity, enabled by rational molecular design and machine learning analyses, enable the development of superhigh-e fluid materials (dielectric permittivity, e > 104) with strong second harmonic generation and macroscopic spontaneous polar ordering.
Journal ArticleDOI
Ferroelectric nematic phase at and below room temperature
TL;DR: In this paper, a liquid crystal was shown to show ferroelectricity at room temperature, without the formation of a con-formation of the nematic phase from the isotropic phase.
Journal ArticleDOI
Multiple Polar and Non-polar Nematic Phases.
Stevie Brown,Ewan Cruickshank,John Storey,Corrie T. Imrie,Damian Pociecha,Magdalena Majewska,Anna Makal,Ewa Gorecka +7 more
TL;DR: In this paper, liquid-crystal materials exhibiting up to three nematic phases are reported, and the modification of the molecular structure by increasing the number of lateral fluorine substituents leads to one of the materials showing a direct isotropic- ferronematic phase transition.
Journal ArticleDOI
On the molecular origins of the ferroelectric splay nematic phase.
TL;DR: In this article, the authors compare two materials of similar chemical structure and demonstrate that just a subtle change in the molecular structure enables denser packing of the molecules when they exhibit polar order, which shows that reduction of excluded volume is in the origin of the polar nematic phase.
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