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Related papers: Knotted Defects in Nematic Liquid Crystals

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We exploit the long-ranged elastic fields inherent to confined nematic liquid crystals to assemble colloidal particles trapped at the liquid crystal interface into reconfigurable structures with complex symmetries and packings. Spherical…

Topological defects in active liquid crystals can be confined by introducing gradients of activity. Here, we examine the dynamical behavior of two defects confined by a sharp gradient of activity that separates an active circular region and…

Soft Condensed Matter · Physics 2021-06-16 Ali Mozaffari , Rui Zhang , Noe Atzin , Juan J. de Pablo

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

The homotopy theory of topological defects is a powerful tool for organizing and unifying many ideas across a broad range of physical systems. Recently, experimental progress has been made in controlling and measuring colloidal inclusions…

Soft Condensed Matter · Physics 2012-04-10 Gareth P. Alexander , Bryan Gin-ge Chen , Elisabetta A. Matsumoto , Randall D. Kamien

Recent experimental observations have suggested that topological defects can facilitate the creation of sharp features in developing embryos. Whereas these observations echo established knowledge about the interplay between geometry and…

Soft Condensed Matter · Physics 2023-07-25 Ludwig A. Hoffmann , Livio Nicola Carenza , Luca Giomi

Topological defects are singularities in material fields that play a vital role across a range of systems: from cosmic microwave background polarization to superconductors, and biological materials. Although topological defects and their…

Soft Condensed Matter · Physics 2017-10-06 Luca Giomi , Žiga Kos , Miha Ravnik , Anupam Sengupta

Colloidal rods immersed in a thermotropic liquid-crystalline solvent are at the basis of so-called hybrid liquid crystals which are characterized by tunable nematic fluidity with symmetries ranging from conventional uniaxial nematic or…

Soft Condensed Matter · Physics 2021-07-28 B. Senyuk , H. Mundoor , I. I. Smalyukh , H. H. Wensink

We use molecular dynamics to study the ordering of a nematic liquid crystal around a spherical particle or droplet. Homeotropic boundary conditions and strong anchoring create a hedgehog director configuration on the particle surface and in…

Soft Condensed Matter · Physics 2013-03-19 D. Andrienko , G. Germano , M. P. Allen

We consider a phenomenological continuum theory for an extensile, overdamped active nematic liquid crystal, applicable in the dense regime. Constructed from general principles, the theory is universal, with parameters independent of any…

Soft Condensed Matter · Physics 2015-06-12 Elias Putzig , Gabriel S. Redner , Arvind Baskaran , Aparna Baskaran

We describe the basic properties and consequences of introducing active stresses, with principal direction along the local director, in cholesteric liquid crystals. The helical ground state is found to be linearly unstable to extensile…

Topological defects play a central role in the formation and organization of various biological systems. Historically, such nonequilibrium defects have been mainly studied in the context of homogeneous active nematics. Phase-separated…

Soft Condensed Matter · Physics 2023-07-13 Timo Krüger , Ivan Maryshev , Erwin Frey

We establish how active stress globally affects the morphology of disclination lines of a three dimensional active nematic liquid crystal under chaotic flow. Thanks to a defect detection algorithm based on the local nematic orientation, we…

Soft Condensed Matter · Physics 2025-06-30 Pasquale Digregorio , Cecilia Rorai , Ignacio Pagonabarraga , Federico Toschi

Disclination lines in three-dimensional nematic liquid crystals generically form closed loops whose topology is classified by homotopy theory. While this classification successfully captures global topological features, it does not encode…

Soft Condensed Matter · Physics 2026-05-27 F. Aprile , A. J. H. Houston , G. Gonnella , D. Marenduzzo , T. N. Shendruk , G. Negro

We present observations of strength one defects and antidefects formed in isotropic-nematic phase transition in a thin layer of nematic liquid crystals, using a cross-polarizer setup. We measure the widths of the distributions of {\it net}…

High Energy Physics - Phenomenology · Physics 2009-10-31 Sanatan Digal , Rajarshi Ray , Ajit M. Srivastava

Confining a liquid crystal imposes topological constraints on the orientational order, allowing global control of equilibrium systems by manipulation of anchoring boundary conditions. In this article, we investigate whether a similar…

Nematic colloids exhibit a large diversity of topological defects and structures induced by colloidal particles in the orientationally ordered liquid crystal host fluids. These defects and field configurations define elastic interactions…

Soft Condensed Matter · Physics 2016-12-30 Bohdan Senyuk , Qingkun Liu , Ye Yuan , Ivan I. Smalyukh

The geometric shape, symmetry, and topology of colloidal particles often allow for controlling colloidal phase behavior and physical properties of these soft matter systems. In liquid crystalline dispersions, colloidal particles with low…

Soft Condensed Matter · Physics 2024-10-14 Ye Yuan , Ivan I. Smalyukh

We numerically model a two-dimensional active nematic confined by a periodic array of fixed obstacles. Even in the passive nematic, the appearance of topological defects is unavoidable due to planar anchoring by the obstacle surfaces. We…

Soft Condensed Matter · Physics 2024-01-25 Cody D. Schimming , C. J. O. Reichhardt , C. Reichhardt

A time crystal is a time dependent physical system that does not reach a standstill, even in state of minimum energy. Here we show that the stability of a time crystal can be enhanced by its topology. For this we simulate time crystals made…

Pattern Formation and Solitons · Physics 2019-10-31 Jin Dai , Xubiao Peng , Antti J. Niemi

Stability is an important and fruitful avenue of research for liquid crystal elastomers. At constant temperature, upon stretching, the homogeneous state of a nematic body becomes unstable, and alternating shear stripes develop at very low…

Soft Condensed Matter · Physics 2021-05-17 L. Angela Mihai , Alain Goriely