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Related papers: Defect order in active nematics on a curved surfac…

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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

A nematic membrane is a sheet with embedded orientational order, which can occur in biological cells, liquid crystal films, manufactured materials, and other soft matter systems. By formulating the free energy of nematic films using tensor…

Soft Condensed Matter · Physics 2009-11-13 John R. Frank , Mehran Kardar

Topological defects play a prominent role in the physics of two-dimensional materials. When driven out of equilibrium in active nematics, disclinations can acquire spontaneous self-propulsion and drive self-sustained flows upon…

Soft Condensed Matter · Physics 2019-12-06 Suraj Shankar , M. Cristina Marchetti

We describe the flows and morphological dynamics of topological defect lines and loops in three-dimensional active nematics and show, using theory and numerical modelling, that they are governed by the local profile of the orientational…

Soft Condensed Matter · Physics 2020-03-13 Jack Binysh , Žiga Kos , Simon Čopar , Miha Ravnik , Gareth P. Alexander

We use numerical modelling to study the flow patterns of an active nematic confined in a cylindrical capillary, considering both planar and homeotropic boundary conditions. We find that active flow emerges not only along the capillary axis…

Soft Condensed Matter · Physics 2015-06-12 Miha Ravnik , Julia M. Yeomans

Topological defects are one of the most conspicuous features of liquid crystals. In two dimensional nematics, they have been shown to behave effectively as particles with both, charge and orientation, which dictate their interactions. Here,…

Soft Condensed Matter · Physics 2021-07-14 Daniel J. G. Pearce , Karsten Kruse

We report an experimental study of the development of orientational order in a crumpled sheet, with a particular focus on the role played by the geometry of confinement. Our experiments are performed on elastomeric sheets immersed in a…

Soft Condensed Matter · Physics 2014-10-30 Anne Dominique Cambou , Narayanan Menon

Coupling between flow and orientation is a central issue in understanding the collective dynamics of active biofilaments and cells. Active stresses generated by motor activity destroy (quasi-)long-range orientational order and induce…

Soft Condensed Matter · Physics 2025-06-04 Yutaka Kinoshita , Nariya Uchida

The persistent dynamics in systems out of equilibrium, particularly those characterized by annihilation and creation of topological defects, is known to involve complicated spatiotemporal processes and is deemed difficult to control. Here…

Soft Condensed Matter · Physics 2022-11-22 Zhi-Feng Huang , Hartmut Löwen , Axel Voigt

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

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 present a hydrodynamic model for a thin spherical shell of active nematic liquid crystal with an arbitrary configuration of defects. The active flows generated by defects in the director lead to the formation of stable vortices,…

Soft Condensed Matter · Physics 2017-11-13 Diana Khoromskaia , Gareth P. Alexander

Active nematics in two dimensions stir themselves efficiently through internally generated chaotic flows, largely driven by motile $+1/2$ disclinations. We investigate how this tendency toward chaotic fluid stirring can, counterintuitively,…

We derive and numerically solve a surface active nematodynamics model. We validate the numerical approach on a sphere and analyse the influence of hydrodynamics on the oscillatory motion of topological defects. For ellipsoidal surfaces the…

Soft Condensed Matter · Physics 2022-09-07 Michael Nestler , Axel Voigt

We investigate the dynamics of elastic capsules suspended in two-dimensional active nematic fluids using lattice Boltzmann simulations. The capsules, modeled as flexible membranes enclosing active internal regions, exhibit a rich variety of…

Soft Condensed Matter · Physics 2026-04-13 Júlio P. A. Santos , Margarida M. Telo da Gama , Rodrigo C. V. Coelho

From incompressible flows to electrostatics, harmonic functions can provide solutions to many two-dimensional problems and, similarly, the director field of a planar nematic can be determined using complex analysis. We derive a closed-form…

Soft Condensed Matter · Physics 2024-12-03 Simon Čopar , Žiga Kos

We investigate the effect of an anisotropic substrate on the turbulent dynamics of a simulated two dimensional active nematic. This is introduced as an anisotropic friction and an effective anisotropic viscosity, with the orientation of the…

Soft Condensed Matter · Physics 2019-06-12 D. J. G. Pearce

We use continuum simulations to study the impact of friction on the ordering of defects in an active nematic. Even in a frictionless system, +1/2 defects tend to align side-by-side and orient antiparallel reflecting their propensity to…

Soft Condensed Matter · Physics 2020-11-25 Kristian Thijssen , Mehrana R. Nejad , Julia M. Yeomans

We characterise the particlelike kinematics of charge-carrying topological defects in nematic media via a geometric field theory. This differs from the theory of electromagnetism, with which it is often compared, due to the absence of…

Soft Condensed Matter · Physics 2026-05-22 Joseph Pollard , Richard G. Morris

We study numerically some possible vortex configurations in a rotating cylinder that is tilted with respect to the rotation axis and where different numbers of vortices can be present at given rotation velocity. In a long cylinder at small…

Other Condensed Matter · Physics 2009-08-04 R. Hänninen