English
Related papers

Related papers: Defect configuration of an active nematic around a…

200 papers

Topological defects are a ubiquitous phenomenon in diverse physical systems. In nematic liquid crystals (LCs), they are dynamic, physicochemically distinct, sensitive to stimuli, and are thereby promising for a range of applications.…

Soft Condensed Matter · Physics 2023-12-25 Shengzhu Yi , Hao Chen , Xinyu Wang , Miao Jiang , Bo Li , Qi-huo Wei , Rui Zhang

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

The self-propulsion of +1/2 topological defects is a hallmark of active nematic fluids, where the defects are advected by the flow field they themselves generate. In this paper we propose a minimal model for defect self-propulsion in a…

Soft Condensed Matter · Physics 2025-08-08 Fridtjof Brauns , Myles O'Leary , Arthur Hernandez , Mark J. Bowick , M. Cristina Marchetti

Topological defects are ubiquitous on surfaces with orientational order fields. Here, we study equilibrium states generated by the feedback between geometry and nematic order on fluid membranes with an integer topological defect. When the…

Soft Condensed Matter · Physics 2024-11-14 D. J. G. Pearce , C. Thibault , Q. Chaboche , C. Blanch-Mercader

We investigate the turbulent dynamics of a two-dimensional active nematic liquid crystal con- strained on a curved surface. Using a combination of hydrodynamic and particle-based simulations, we demonstrate that the fundamental structural…

Soft Condensed Matter · Physics 2019-05-01 D. J. G. Pearce , Perry W. Ellis , Alberto Fernandez-Nieves , L. Giomi

Topological defects play a key role in two-dimensional active nematics, and a transient role in two-dimensional active polar fluids. In this paper, we study both the transient and long-time behavior of defects in two-dimensional active…

Soft Condensed Matter · Physics 2020-09-24 Farzan Vafa

We study a continuum model of an extensile active nematic to show that mesoscale turbulence develops in two stages: (i) ordered regions undergo an intrinsic hydrodynamic instability generating walls, lines of stong bend deformations, (ii)…

Soft Condensed Matter · Physics 2015-06-18 Sumesh P. Thampi , Ramin Golestanian , Julia M. Yeomans

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

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

Inspired by recent experiments that highlight the role of nematic defects in the morphogenesis of epithelial tissues, we develop a minimal framework to study the dynamics of an active curved surface driven by its nematic texture. Allowing…

Soft Condensed Matter · Physics 2022-09-14 Farzan Vafa , L. Mahadevan

Active fluids, such as cytoskeletal filaments, bacterial colonies and epithelial cell layers, exhibit distinctive orientational coherence, often characterized by nematic order and topological defects. By contrast, little is known about…

Soft Condensed Matter · Physics 2021-04-07 Mattia Serra , Linnea Lemma , Luca Giomi , Zvonimir Dogic , L. Mahadevan

Point-like motile topological defects control the universal dynamics of diverse two-dimensional active nematics ranging from shaken granular rods to cellular monolayers. A comparable understanding in higher dimensions has yet to emerge. We…

In two dimensional nematics, topological defects are point like singularities with both a charge and a phase. We study topological defects within curved nematic textures on the surface of a cylinder. This allows us to isolate the effect of…

Soft Condensed Matter · Physics 2022-05-10 Daniel J. G. Pearce

Topological defects are a conspicuous feature of active liquid crystals that have been associated with important morphogenetic transitions in organismal development. Robust development thus requires a tight control of the motion and…

Non-equilibrium dynamics of topological defects can be used as a fundamental propulsion mechanism in microscopic active matter. Here, we demonstrate swimming of topological defect-propelled colloidal particles in (passive) nematic fluids…

Soft Condensed Matter · Physics 2021-09-30 Tianyi Yao , Žiga Kos , Yimin Luo , Edward B. Steager , Miha Ravnik , Kathleen J. Stebe

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

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…

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 topological properties of many materials are central to their behavior, with the dynamics of topological defects being particularly important to intrinsically out-of-equilibrium, active materials. In this paper, local manipulation of…

Soft Condensed Matter · Physics 2019-11-01 David P. Rivas , Tyler N. Shendruk , Robert R. Henry , Daniel H. Reich , Robert L. Leheny

We present a novel framework for the study of disclinations in two-dimensional active nematic liquid crystals, and topological defects in general. The order tensor formalism is used to calculate exact multi-particle solutions of the…

Soft Condensed Matter · Physics 2018-02-28 Dario Cortese , Jens Eggers , Tanniemola B. Liverpool