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Related papers: Point Defects, Chirality and Singularity Theory in…

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We investigate experimentally and numerically the defect configurations emerging when a cholesteric liquid crystal is confined to a spherical shell. We uncover a rich scenario of defect configurations, some of them non-existent in nematic…

Soft Condensed Matter · Physics 2017-09-13 Alexandre Darmon , Michael Benzaquen , Simon Čopar , Olivier Dauchot , Teresa Lopez-Leon

Using computer simulations we investigate the microscopic structure of the singular director field within a nematic droplet. As a theoretical model for nematic liquid crystals we take hard spherocylinders. To induce an overall topological…

Soft Condensed Matter · Physics 2009-10-31 J. Dzubiella , M. Schmidt , H. Loewen

Liquid crystals formed of bent-core molecules are exotic materials that exhibit the twist-bend nematic phase. This arises when an energetic preference for nonzero local bend distortion is accommodated via twist in the texture, resulting in…

Soft Condensed Matter · Physics 2025-05-23 Joseph Pollard , Richard G. Morris

We give a topological classification of defect lines in cholesteric liquid crystals using methods from contact topology. By focusing on the role played by the chirality of the material, we demonstrate a fundamental distinction between…

Soft Condensed Matter · Physics 2023-06-14 Joseph Pollard , Gareth P. Alexander

The description of point defects in chiral liquid crystals via topological methods requires the introduction of singular contact structures, a generalisation of regular contact structures where the plane field may have singularities at…

Symplectic Geometry · Mathematics 2019-11-25 Joseph Pollard , Gareth P. Alexander

Handedness of the director twist in cholesteric liquid crystals is commonly assumed to be the same throughout the medium, determined solely by the chirality of constituent molecules or chiral additives, albeit distortions of the…

Soft Condensed Matter · Physics 2017-04-26 P. J. Ackerman , I. I. Smalyukh

This paper reviews the complex ordered structures induced by chirality in liquid crystals. In general, chirality favors a twist in the orientation of liquid-crystal molecules. In some cases, as in the cholesteric phase, this favored twist…

Soft Condensed Matter · Physics 2009-10-31 Randall D. Kamien , Jonathan V. Selinger

We study the topology of smectic defects in two and three dimensions. We give a topological classification of smectic point defects and disclination lines in three dimensions. In addition we describe the combination rules for smectic point…

Soft Condensed Matter · Physics 2019-11-19 Thomas Machon , Hillel Aharoni , Yichen Hu , Randall D. Kamien

Specific features of the defect modes of cholesteric liquid crystals (CLCs) with an isotropic defect, as well as their photonic density of states, Q factor, and emission, have been investigated. The effect of the thicknesses of the defect…

The transition from a nematic to an isotropic state in a self-closing spherical liquid crystal shell with tangential alignment is a stimulating phenomenon to investigate, as the topology dictates that the shell exhibits local isotropic…

Soft Condensed Matter · Physics 2024-02-02 Yucen Han , Jan Lagerwall , Apala Majumdar

Widely known for their uses in displays and electro-optics, liquid crystals are more than just technological marvels. They vividly reveal the topology and structure of various solitonic and singular field configurations, often markedly…

Soft Condensed Matter · Physics 2023-04-18 Jin-Sheng Wu , Ivan I. Smalyukh

We present a novel, self-consistent and robust theoretical model to investigate elastic interactions between topological defects in liquid crystal shells. Accounting for the non-concentric nature of the shell in a simple manner, we are able…

Soft Condensed Matter · Physics 2016-12-14 Alexandre Darmon , Olivier Dauchot , Teresa Lopez-Leon , Michael Benzaquen

Cholesteric liquid crystals experience geometric frustration when they are confined between surfaces with anchoring conditions that are incompatible with the cholesteric twist. Because of this frustration, they develop complex topological…

Soft Condensed Matter · Physics 2017-08-02 Sajedeh Afghah , Jonathan V. Selinger

Molecular chirality leads to a wonderful variety of equilibrium structures, from the simple cholesteric phase to the twist-grain-boundary phases, and it is responsible for interesting and technologically important materials like…

Soft Condensed Matter · Physics 2007-05-23 T. C. Lubensky , A. B. Harris , Randall D. Kamien , Gu Yan

Most theoretical descriptions of lyotropic cholesteric liquid crystals to date focus on homogeneous systems in which the rod concentration, as opposed to the rod orientation, is uniform. In this work, we build upon the Onsager-Straley…

Soft Condensed Matter · Physics 2017-08-10 H. H. Wensink , C. Ferreiro-Córdova

The fundamental issues of symmetry related to chirality are discussed and applied to simple situations relevant to liquid crystals. We show that any chiral measure of a geometric object is a pseudoscalar (invariant under proper rotations…

Statistical Mechanics · Physics 2009-10-31 A. B. Harris , Randall D. Kamien , T. C. Lubensky

Topological defects are distinctive signatures of liquid crystals. They profoundly affect the viscoelastic behavior of the fluid by constraining the orientational structure in a way that inevitably requires global changes not achievable…

Soft Condensed Matter · Physics 2015-06-19 Luca Giomi , Mark J. Bowick , Prashant Mishra , Rastko Sknepnek , M. Cristina Marchetti

Liquid crystals generally support orientational singularities of the director field known as topological defects. These latter modifiy transport properties in their vicinity as if the geometry was non-Euclidean. We present a state of the…

Soft Condensed Matter · Physics 2023-07-06 Sébastien Fumeron , Bertrand Berche , Fernando Moraes

Liquid crystals are assemblies of rod-like molecules which self-organize to form mesophases, in-between ordinary liquids and anisotropic crystals. At each point, the molecules collectively orient themselves along a privileged direction,…

Soft Condensed Matter · Physics 2023-05-03 Sébastien Fumeron , Bertrand Berche

This study investigates the influence of chirality, viscous effects, and confinement geometry on the flow dynamics and defect structures of cholesteric liquid crystals (CLCs) using numerical simulations. As chiral strength increases,…

Soft Condensed Matter · Physics 2025-09-05 Isreal Morawo , Dana Grecov
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