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Related papers: Dynamics of defects in active nematics

200 papers

Colloidal inclusions in nematic fluids induce topological defects that govern their dynamics. These defects create well-understood rheological behavior in passive nematics, but the interplay between colloid-associated defects and…

Soft Condensed Matter · Physics 2025-03-26 Timofey Kozhukhov , Benjamin Loewe , Kristian Thijssen , Tyler N. Shendruk

The study of liquid crystals at equilibrium has led to fundamental insights into the nature of ordered materials, as well as to practical applications such as display technologies. Active nematics are a fundamentally different class of…

Soft Condensed Matter · Physics 2015-08-19 Stephen J. DeCamp , Gabriel S. Redner , Aparna Baskaran , Michael F. Hagan , Zvonimir Dogic

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

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

The effects of an electric field on the flow patterns and defect dynamics of two-dimensional active nematics are numerically investigated. We found that field-induced director reorientation causes anisotropic active turbulence characterized…

Soft Condensed Matter · Physics 2023-07-20 Yutaka Kinoshita , Nariya Uchida

We perform dynamical simulations of a two-dimensional active nematic fluid in coexistence with an isotropic fluid. Drops of active nematic become elongated, and an effective anchoring develops at the nematic-isotropic interface. The…

Soft Condensed Matter · Physics 2014-12-17 Matthew L. Blow , Sumesh P. Thampi , Julia M. Yeomans

Starting from a three-dimensional description of an active nematic layer, we employ an asymptotic theory to derive a series of low-dimensional continuum models that capture the coupled dynamics of flat and curved films, including variations…

Soft Condensed Matter · Physics 2025-06-23 Mehrana R. Nejad , L. Mahadevan

We study emergent dynamics in a viscous drop subject to interfacial nematic activity. Using hydrodynamic simulations, we show how the interplay of nematodynamics, activity-driven flows and surface deformations gives rise to a sequence of…

Soft Condensed Matter · Physics 2024-04-19 Mohammadhossein Firouznia , David Saintillan

We propose a reaction-diffusion system that converts topological information of an active nematic into chemical signals. We show that a curvature-activated reaction dipole is sufficient for creating a system that dynamically senses topology…

Soft Condensed Matter · Physics 2025-01-09 Michael M. Norton , Piyush Grover

Two-dimensional active nematics are often modeled using phenomenological continuum theories that describe the dynamics of the nematic director and fluid velocity through partial differential equations (PDEs). While these models provide a…

Using novel micro-printing techniques, we develop a versatile experimental setup that allows us to study how lateral confinement tames the active flows and defect properties of the microtubule/kinesin active nematic system. We demonstrate…

We describe a numerical investigation of a continuum model of an active nematic, concentrating on the regime of active turbulence. Results are presented for the effect of three parameters, activity, elastic constant and rotational diffusion…

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

We develop a description of defect loops in three-dimensional active nematics based on a multipole expansion of the far-field director and show how this leads to a self-dynamics dependent on the loop's geometric type. The dipole term leads…

Soft Condensed Matter · Physics 2022-06-15 Alexander J. H. Houston , Gareth P. Alexander

We investigate the dynamics of active nematic liquid crystals on deformable membranes, focusing on the interplay between active stress and anisotropic curvature coupling. Using a minimal model, we simulate the coupled evolution of the…

Soft Condensed Matter · Physics 2026-05-19 Yuki Hirota , Nariya Uchida

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

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…

We report on the emergence of stable self-propelled bound defects in monolayers of active nematics, which form virtual full-integer topological defects in the form of vortices and asters. Through numerical simulations and analytical…

Soft Condensed Matter · Physics 2020-10-26 Kristian Thijssen , Amin Doostmohammadi

Active nematics are out-of-equilibrium systems in which energy injection at the microscale drives emergent collective behaviors, from spontaneous flows to active turbulence. While the dynamics of these systems have been extensively studied,…

Soft Condensed Matter · Physics 2025-04-15 Ahmet Umut Akduman , Yusuf Sariyar , Giuseppe Negro , Livio Nicola Carenza

We adapt the Halperin-Mazenko formalism to analyze two-dimensional active nematics coupled to a generic fluid flow. The governing hydrodynamic equations lead to evolution laws for nematic topological defects and their corresponding density…

Soft Condensed Matter · Physics 2021-05-11 Luiza Angheluta , Zhitao Chen , M. Cristina Marchetti , Mark J. Bowick

We study the active flow around isolated defects and the self-propulsion velocity of $+1/2$ defects in an active nematic film with both viscous dissipation (with viscosity $\eta$) and frictional damping $\Gamma$ with a substrate. The…

Soft Condensed Matter · Physics 2022-01-28 Jonas Rønning , M. Cristina Marchetti , Mark J. Bowick , Luiza Angheluta