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Related papers: The Topology of Dislocations in Smectic Liquid Cry…

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Smectic liquid crystals are charcterized by layers that have a preferred uniform spacing and vanishing curvature in their ground state. Dislocations in the smectics play an important role in phase nucleation, layer reorientation, and…

Soft Condensed Matter · Physics 2017-06-28 Hillel Aharoni , Thomas Machon , Randall D. Kamien

Volterra's definition of dislocations in crystals distinguishes edge and screw defects geometrically, according to whether the Burgers vector is perpendicular or parallel to the defect. Here, we demonstrate a distinction between screw and…

Materials Science · Physics 2024-01-25 Paul G. Severino , Randall D. Kamien

In this work, we investigate the topological properties of knotted defects in smectic liquid crystals. Our story begins with screw dislocations, whose radial surface structure can be smoothly accommodated on $S^3$ for fibred knots by using…

Soft Condensed Matter · Physics 2025-06-16 Paul G. Severino , Randall D. Kamien , Benjamin Bode

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

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

Smectic orders on curved substrates can be described by differential forms of rank one (1-forms), whose geometric meaning is the differential of the local phase field of density modulation. The exterior derivative of 1-form is the local…

Soft Condensed Matter · Physics 2009-11-13 Xiangjun Xing

A flux liquid can condense into a smectic crystal in a pure layered superconductors with the magnetic field oriented nearly parallel to the layers. If the smectic order is commensurate with the layering, this crystal is {\sl stable} to…

Condensed Matter · Physics 2009-10-22 Leon Balents , David R. Nelson

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

Smectic liquid crystals are materials formed by stacking deformable, fluid layers. Though smectics prefer to have flat, uniformly-spaced layers, boundary conditions can impose curvature on the layers. Since the layer spacing and curvature…

Differential Geometry · Mathematics 2007-05-23 Randall D. Kamien , Christian D. Santangelo

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

The goal of this work is to show that, mathematically, screw dislocation loops with distinct topological properties can be introduced locally on a given smectic liquid crystal configuration. Concretely, given a configuration, we show that a…

Mathematical Physics · Physics 2025-09-08 Robert Cardona , Andreu Vega

We show that back-flow, the coupling between the order parameter and the velocity fields, has a significant effect on the motion of defects in nematic liquid crystals. In particular the defect speed can depend strongly on the topological…

Soft Condensed Matter · Physics 2007-05-23 Geza Toth , Colin Denniston , Julia M. Yeomans

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

The homotopy theory of topological defects in ordered media fails to completely characterize systems with broken translational symmetry. We argue that the problem can be understood in terms of the lack of rotational Goldstone modes in such…

Soft Condensed Matter · Physics 2009-09-14 Bryan Gin-ge Chen , Gareth P. Alexander , Randall D. Kamien

We propose a general formalism to characterize orientational frustration of smectic liquid crystals in confinement by interpreting the emerging networks of grain boundaries as objects with a topological charge. In a formal idealization,…

Directional media, such as nematic liquid crystals and ferromagnets, are characterized by their topologically stabilized defects in directional order. In nematics, boundary conditions and surface-treated inclusions often create complex…

Soft Condensed Matter · Physics 2015-06-03 Simon Čopar , Slobodan Žumer

Smectic order on arbitrary curved substrate can be described by a differential form of rank one (1-form), whose geometric meaning is the differential of the local phase field of the density modulation. The exterior derivative of 1-form is…

Soft Condensed Matter · Physics 2009-11-13 Xiangjun Xing

Confined samples of liquid crystals are characterized by a variety of topological defects and can be exposed to external constraints such as extreme confinements with nontrivial topology. Here we explore the intrinsic structure of smectic…

Soft Condensed Matter · Physics 2021-02-03 René Wittmann , Louis B. G. Cortes , Hartmut Löwen , Dirk G. A. L. Aarts

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

Smectic materials represent a unique state between fluids and solids, characterized by orientational and partial positional order, making them notoriously difficult to model, particularly in confining geometries. We propose a complex order…

Soft Condensed Matter · Physics 2023-03-22 Jack Paget , Marco G. Mazza , Andew J. Archer , Tyler N. Shendruk
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