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Related papers: Flexoelectricity versus Electrostatics in Polar Ne…

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The statistical theory of the dipole flexoelectric (FE) polarization in liquid crystals is used to calculate the temperature dependence of order parameters, the elastic constants and the FE coefficients. Two systems with polar wedge-shaped…

Soft Condensed Matter · Physics 2011-02-10 A. Kapanowski

We present in this paper a detailed analysis of the flexoelectric instability of a planar nematic layer in the presence of an alternating electric field (frequency $\omega$), which leads to stripe patterns (flexodomains) in the plane of the…

Soft Condensed Matter · Physics 2015-05-27 Alexei Krekhov , Werner Pesch , Agnes Buka

Because of their spontaneous bulk polarization, ferroelectric nematic liquid crystals can be easily brought by surface coupling or confinement in a state in which the accumulation of bound charges becomes incompatible with polar order,…

The recent discovery of a new ferroelectric nematic (NF) liquid crystalline phase became of utmost interest for the liquid crystal (LC) and the whole soft and condensed matter fields. Contrary to the previously known ferroelectric LC…

Only a few years have passed since discovery of polar nematics, and now they are becoming the most actively studied liquid crystal materials. Despite numerous breakthrough findings made recently, a theoretical systematization is still…

Soft Condensed Matter · Physics 2023-09-28 A. V. Emelyanenko , V. Yu. Rudyak , F. Araoka , H. Nishikawa , K. Ishikawa

Liquid crystal materials exhibiting up to three nematic phases are reported. Dielectric response measurements show that while the lower temperature nematic phase has ferroelectric order and the highest temperature nematic phase is apolar,…

Soft Condensed Matter · Physics 2021-09-07 S. Brown , E. Cruickshank , J. M. D. Storey , C. T. Imrie , D. Pociecha , M. Majewska , A. Makal , E. Gorecka

In liquid crystals, if flexoelectric couplings between polar order and director gradients are strong enough, the uniform nematic phase can become unstable to formation of a modulated polar phase. Previous theories have predicted two types…

Soft Condensed Matter · Physics 2018-06-21 Shaikh M. Shamid , David W. Allender , Jonathan V. Selinger

The recently discovered ferroelectric nematic liquids incorporate to the functional combination of fluidity, processability and anisotropic optical properties of nematic liquids, an astonishing range of physical properties derived from the…

The phase diagram of ice is complex and contains many phases, but the most common (frozen water at ambient pressure, also known as Ih ice) is a non-polar material despite individual water molecules being polar1,2. Consequently, ice is not…

Materials Science · Physics 2025-05-02 Xin Wen , Qianqian Ma , Anthony Mannino , Marivi Fernandez-serra , Shengping Shen , Gustau Catalan

We have measured the bending-induced polarization of Pb(Mg1/3Nb2/3)O3-PbTiO3 single crystals with compositions at the relaxor-ferroelectric phase boundary. The crystals display very large flexoelectricity, with flexocoupling coefficients an…

Materials Science · Physics 2015-06-18 Jackeline Narvaez , Gustau Catalan

The ferroelectric nematic phase (NF) is a recently discovered phase of matter in which the orientational order of the conventional nematic liquid crystal state is augmented with polar order. Atomistic simulations suggest that the polar NF…

Soft Condensed Matter · Physics 2023-09-26 Charles Parton-Barr , Helen Gleeson , Richard Mandle

We report 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…

We develop a Landau theory for bend flexoelectricity in liquid crystals of bent-core molecules. In the nematic phase of the model, the bend flexoelectric coefficient increases as we reduce the temperature toward the nematic to polar phase…

Soft Condensed Matter · Physics 2013-05-28 Shaikh M. Shamid , Subas Dhakal , Jonathan V. Selinger

Ferroelectric nematic phases are a new class of polar fluids in which spontaneous polarization is directly coupled to the orientational order, providing unique opportunities for creating self-organized materils with spatially modulated…

The free energy of antiferroelectric liquid crystal which takes into account polar order explicitly is presented. Steric, van der Waals, piezoelectric and flexoelectric interactions to the nearest layers and dipolar electrostatic…

Soft Condensed Matter · Physics 2009-11-07 Mojca Cepic , Bostjan Zeks

We report the properties of two new series of compounds that show the ferroelectric nematic phase in which the length of a terminal chain is varied. The longer the terminal chain, the weaker the dipole-dipole interactions of the molecules…

Blue phase liquid crystals are not usually considered to exhibit a flexoelectrooptic effect, due to the polar nature of flexoelectric switching and the cubic or amorphous structure of blue phases. Here, we derive the form of the…

Soft Condensed Matter · Physics 2014-06-13 B. I. Outram , S. J. Elston , F. Castles , M. M. Qasim , H. Coles , H. -Y. Chen , S. -F. Lu

Here we discuss the free energy of nematic liquid crystals using two vectors and the helicity, with the aim of having a compact form of its density. The two vectors are due to the splay and bend distortions of the director field. They have…

Soft Condensed Matter · Physics 2018-05-01 Amelia Carolina Sparavigna

In culture migrating and interacting amoeboid cells can form nematic liquid crystal phases. A polar nematic liquid crystal is formed if the interaction has a polar symmetry. One type of white blood cells (granulocytes) form clusters where…

Biological Physics · Physics 2007-05-23 Ralf Kemkemer , Dieter Kling , Dieter Kaufmann , Hans Gruler

The ferroelectric nematic phase (N$_{\text{F}}$) has quickly become the most studied system in liquid crystal research. In this work, we investigate the origin of such polar structure by studying a compound for which the N$_{\text{F}}$…

Soft Condensed Matter · Physics 2024-11-14 Aitor Erkoreka , Nerea Sebastián , Alenka Mertelj , Josu Martinez-Perdiguero