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Related papers: Defect unbinding in active nematics

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Engineering synthetic materials that mimic the remarkable complexity of living organisms is a fundamental challenge in science and technology. We study the spatiotemporal patterns that emerge when an active nematicfilm of microtubules and…

We numerically study the effect of an active turbulent environment on a passive deformable droplet. The system is simulated using coupled hydrodynamic and nematodynamic equations for nematic liquid crystals with an active stress which is…

Soft Condensed Matter · Physics 2024-05-06 Chamkor Singh , Abhishek Chaudhuri

We investigate the effects of extrinsic curvature on the turbulent behavior of a 2D active nematic confined to the surface of a cylinder. The surface of a cylinder has no intrinsic curvatrue and only extrinsic curvature. A nematic field…

Soft Condensed Matter · Physics 2020-08-26 D. J. G. Pearce

In pulsating active matter, topological defects are motile despite the absence of any macroscopic flows and microscopic self-propulsion. We reveal that this motility arises from a ratchet effect: the mechanochemical coupling between local…

Soft Condensed Matter · Physics 2026-05-26 Luca Casagrande , Alessandro Manacorda , Etienne Fodor

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

How do topological defects affect the degree of order in active matter? To answer this question we investigate an agent-based model of self-propelled particles, which accounts for polar alignment and short-ranged repulsive interactions. For…

Soft Condensed Matter · Physics 2014-04-30 Christoph A. Weber , Christopher Bock , Erwin Frey

The hydrodynamic theory of active nematics has been often used to describe the spatio-temporal dynamics of cell flows and motile topological defects within soft confluent tissues. Those theories, however, often rely on the assumption that…

Soft Condensed Matter · Physics 2023-08-15 Ioannis Hadjifrangiskou , Liam J. Ruske , Julia M. Yeomans

We introduce a two-dimensional active nematic with quenched disorder. We write the coarse-grained hydrodynamic equations of motion for slow variables, viz. density, and orientation. Disorder strength is tuned from zero to large values.…

Soft Condensed Matter · Physics 2021-07-15 Sameer Kumar , Shradha Mishra

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

Using the Born-Oppenheimer approximation, we present a general description of topological defects dynamics in $p$-atic materials on curved surfaces, and simplify it in the case of active nematics. We find that activity induces a geometric…

Soft Condensed Matter · Physics 2023-08-02 Farzan Vafa , David R. Nelson , Amin Doostmohammadi

We measure the defect density as a function of time at different temperatures in simulations of a two dimensional system of interacting particles. Just above the solid to liquid transition temperature, the power spectrum of the defect…

Soft Condensed Matter · Physics 2009-11-07 C. Reichhardt , C. J. Olson Reichhardt

We study dry, dense active nematics at both particle and continuous levels. Specifically, extending the Boltzmann-Ginzburg-Landau approach, we derive well-behaved hydrodynamic equations from a Vicsek-style model with nematic alignment and…

Soft Condensed Matter · Physics 2019-12-20 Aurelio Patelli , Ilyas Djafer-Cherif , Igor S. Aranson , Eric Bertin , Hugues Chaté

We show that the dominant mode of alignment plays an important role in dry active nematics,leading to two dynamical sub-classes defined by the nature of the instability of the nematic bands that characterize, in these systems, the…

Soft Condensed Matter · Physics 2019-01-16 Li-bing Cai , Hugues Chaté , Yu-qiang Ma , Xia-qing Shi

We study the dynamics of active nematic films on a substrate driven by active flows with or without the incompressible constraint.Through simulations and theoretical analysis, we show that arch patterns are stable in the compressible case,…

Soft Condensed Matter · Physics 2022-11-30 Supavit Pokawanvit , Zhitao Chen , Zhihong You , Luiza Angheluta , M. Cristina Marchetti , Mark J. Bowick

We use numerical simulations to investigate the hydrodynamic behavior of the interface between nematic (N) and isotropic (I) phases of a confined active liquid crystal. At low activities, a stable interface with constant shape and velocity…

Soft Condensed Matter · Physics 2021-02-25 Rodrigo C. V. Coelho , Nuno A. M. Araújo , Margarida M. Telo da Gama

Defects are a ubiquitous feature of ordered media. They have certain universal features, independent of the underlying physical system, reflecting their topological origins. While the topological properties of defects are robust, they…

Soft Condensed Matter · Physics 2021-02-24 Chiqun Zhang , Amit Acharya , Alan C. Newell , Shankar C. Venkataramani

We use analytic arguments and numerical solutions of the continuum, active nematohydrodynamic equations to study how friction alters the behaviour of active nematics. Concentrating on the case where there is nematic ordering in the passive…

Soft Condensed Matter · Physics 2024-04-23 Mehrana Raeisian Nejad , Amin Doostmohammadi , Julia Mary Yeomans

We numerically study two-dimensional active nematics with periodic activity patterning. For stripes of activity, we observe a transition from two-dimensional to one-dimensional active turbulence as the maximum active force and distance…

Soft Condensed Matter · Physics 2025-03-11 Cody D. Schimming , C. J. O. Reichhardt , C. Reichhardt

Cell layers are often categorized as contractile or extensile active nematics but recent experiments on neural progenitor cells with induced $+1$ topological defects challenge this classification. In a bottom-up approach, we first study a…

Soft Condensed Matter · Physics 2024-09-13 Zihui Zhao , Yisong Yao , He Li , Yongfeng Zhao , Yujia Wang , Hepeng Zhang , Hugues Chat'e , Masaki Sano

Active matter is characterized by its ability to induce motion by self-generated stress. In the case of a solid, such motion can lead to shape transformations. The stress-generating components can be anisotropic endowing the material with…

Soft Condensed Matter · Physics 2022-05-16 D. J. G. Pearce , S. Gat , G. Livne , A. Bernheim-Groswasser , K. Kruse