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Related papers: Knotted Defects in Nematic Liquid Crystals

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Knots are entangled structures that cannot be untangled without a cut. Topological stability of knots is one of the many examples of their important properties that can be used in information storage and transfer. Knot dynamics is important…

Soft Condensed Matter · Physics 2022-11-04 Hyo Jung Park , Anna Lappala

Linear defects such as dislocations and disclinations in ordered materials attract foreign particles since they replace strong elastic distortions at the defect cores. In this work, we explore the behavior of isotropic droplets nucleating…

Recent numerical simulations of hard helical particle systems unveiled the existence of a novel chiral nematic phase, termed screw-like, characterised by the helical organization of the particle C$_2$ symmetry axes round the nematic…

Soft Condensed Matter · Physics 2018-01-17 Giorgio Cinacchi , Alberta Ferrarini , Achille Giacometti , Hima Bindu Kolli

From the mitotic spindle up to tissues and biofilms, many biological systems behave as active droplets, which often break symmetry and change shape spontaneously. Here, I show that active nematic droplets can experience a fingering…

Soft Condensed Matter · Physics 2022-06-07 Ricard Alert

Links and knots are exotic topological structures that have garnered significant interest across multiple branches of natural sciences. Coherent links and knots, such as those constructed by phase or polarization singularities of coherent…

Optics · Physics 2025-04-08 Zhuoyi Wang , Xingyuan Lu , Zhigang Chen , Yangjian Cai , Chengliang Zhao

We show that topological defects in an ion-doped nematic liquid crystal can be used to manipulate the surface charge distribution on chemically homogeneous, charge-regulating external surfaces, using a minimal theoretical model. In…

Soft Condensed Matter · Physics 2020-07-16 Miha Ravnik , Jeffrey C. Everts

Liquid crystals can self-organize into a layered smectic phase. While the smectic layers are typically straight forming a lamellar pattern in bulk, external confinement may drastically distort the layers due to the boundary conditions…

We present a general analysis of two-dimensional optical lattice models that give rise to topologically non-trivial insulating states. We identify the main ingredients of the lattice models that are responsible for the non-trivial…

Quantum Gases · Physics 2010-07-13 Tudor D. Stanescu , Victor Galitski , S. Das Sarma

There are two prominent applications of the mathematical concept of topology to the physics of materials: band topology, which classifies different topological insulators and semimetals, and topological defects that represent immutable…

Materials Science · Physics 2022-08-11 Zhi-Kang Lin , Qiang Wang , Yang Liu , Haoran Xue , Baile Zhang , Yidong Chong , Jian-Hua Jiang

Systems with holes, such as colloidal handlebodies and toroidal droplets, have been studied in the nematic liquid crystal (NLC) 4-cyano-4'-pentylbiphenyl (5CB): both point and ring topological defects can occur within each hole and around…

Soft Condensed Matter · Physics 2023-12-01 Lisa Tran , Maxim O. Lavrentovich , Daniel A. Beller , Ningwei Li , Kathleen J. Stebe , Randall D. Kamien

Active materials are capable of converting free energy into directional motion, giving rise to striking dynamical phenomena. Developing a general understanding of their structure in relation to the underlying non-equilibrium physics would…

Soft Condensed Matter · Physics 2018-10-17 Nitin Kumar , Rui Zhang , Juan J. de Pablo , Margaret L. Gardel

Active nematics contain topological defects which under sufficient activity move, create and annihilate in a chaotic quasi-steady state, called active turbulence. However, understanding active defects under confinement is an open challenge,…

Soft Condensed Matter · Physics 2019-10-02 Simon Čopar , Jure Aplinc , Žiga Kos , Slobodan Žumer , Miha Ravnik

The lectures review the state of affairs in modern branch of mathematical physics called probabilistic topology. In particular we consider the following problems: (i) We estimate the probability of a trivial knot formation on the lattice…

Statistical Mechanics · Physics 2007-05-23 Sergei Nechaev

Disclinations lines play a key role in many physical processes, from the fracture of materials to the formation of the early universe. Achieving versatile control over disclinations is key to developing novel electro-optical devices,…

Soft Condensed Matter · Physics 2023-06-28 Alvin Modin , Biswarup Ash , Kelsey Ishimoto , Robert L. Leheny , Francesca Serra , Hillel Aharoni

We develop a theory of point defects in cholesterics and textures in spherical droplets with normal anchoring. The local structure of chiral defects is described by singularity theory and a smectic-like gradient field establishing a nexus…

Soft Condensed Matter · Physics 2019-04-11 Joseph Pollard , Gregor Posnjak , Gareth P. Alexander , Simon Copar , Igor Musevic

Using numerical simulations of the full nonlinear equations of motion we investigate topological solitons of a modified O(3) sigma model in three space dimensions, in which the solitons are stabilized by the Hopf charge. We find that for…

High Energy Physics - Theory · Physics 2009-10-31 Richard Battye , Paul Sutcliffe

Nematic liquid crystals confined to geometrically as well as chemically patterned substrate on one end and a flat substrate with strong anchoring on the other is studied using non-Boltzmann Monte Carlo methods. We observe significant…

Soft Condensed Matter · Physics 2010-10-18 D. Jayasri , Regina Jose , K. P. N. Murthy , V. S. S. Sastry

Stable array of point defects was generated in nematic liquid crystal. Point defects with topological charge of +1 and -1 (hedgehogs) were generated in vertically aligned liquid crystal cell. The hedgehogs were arranged in square or…

Soft Condensed Matter · Physics 2019-06-18 Jieh-Wen Tsung

Liquid crystals have proven to provide a versatile experimental and theoretical platform for studying topological objects such as vortices, skyrmions, and hopfions. In parallel, in hard condensed matter physics, the concept of topological…

Soft Condensed Matter · Physics 2025-02-13 Cuiling Meng , Jin-Sheng Wu , Žiga Kos , Jörn Dunkel , Cristiano Nisoli , Ivan I. Smalyukh

We formulate a model for a point defect embedded in a homogeneous multilattice crystal with an empirical interatomic potential interaction. Under a natural, phonon stability assumption we quantify the decay of the long-range elastic fields…

Analysis of PDEs · Mathematics 2016-10-03 Derek Olson , Christoph Ortner