English
Related papers

Related papers: Defect Line Coarsening and Refinement in Active Ne…

200 papers

Liquid crystals inevitably possess topological defect excitations generated through boundary conditions, applied fields or in quenches to the ordered phase. In equilibrium pairs of defects coarsen and annihilate as the uniform ground state…

Soft Condensed Matter · Physics 2013-06-05 Luca Giomi , Mark J. Bowick , Xu Ma , M. Cristina Marchetti

Topological defects are at the root of the large-scale organization of liquid crystals. In two-dimensional active nematics, two classes of topological defects of charges $\pm 1/2$ are known to play a major role due to active stresses.…

Soft Condensed Matter · Physics 2022-04-08 Louis Brézin , Thomas Risler , Jean-François Joanny

A nematic liquid crystal confined to the surface of a sphere exhibits topological defects of total charge $+2$ due to the topological constraint. In equilibrium, the nematic field forms four $+1/2$ defects, located at the corners of a…

Soft Condensed Matter · Physics 2020-07-22 Yi-Heng Zhang , Markus Deserno , Zhan-Chun Tu

Confined active nematics exhibit rich dynamical behavior, including spontaneous flows, periodic defect dynamics, and chaotic `active turbulence'. Here, we study these phenomena using the framework of Exact Coherent Structures, which has…

Soft Condensed Matter · Physics 2022-01-26 Caleb G. Wagner , Michael M. Norton , Jae Sung Park , Piyush Grover

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

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

Active matter locally converts chemical energy into mechanical work and, for this reason, it provides new mechanisms of pattern formation. In particular, active gels made of protein motors and filaments are far-from-equilibrium systems that…

When a nematic liquid crystal is confined in a porous medium with strong anchoring conditions, topological defects, called disclinations, are stably formed with numerous possible configurations. Since the energy barriers between them are…

Soft Condensed Matter · Physics 2015-06-12 Takeaki Araki

We investigate similarities in the micro-structural dynamics between externally driven and actively driven nematics. Walls, lines of strong deformations in the director field, and topological defects are characteristic features of an active…

Soft Condensed Matter · Physics 2015-04-28 Sumesh P. Thampi , Ramin Golestanian , Julia M. Yeomans

We propose an agent-based model of active flexible rods. Inspired by cytoskeletal flows, we introduce activity by an internal flow that contributes to the dissipative forces. The active force between our agents is central and reciprocal,…

Soft Condensed Matter · Physics 2026-03-06 Mathieu Dedenon , Carles Blanch-Mercader , Karsten Kruse , Jens Elgeti

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 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 consider active nematodynamics on deformable surfaces. Based on a thermodynamically consistent surface Beris-Edwards model we add nematic activity and focus on the emerging additional coupling mechanism between the nematic field, the…

Soft Condensed Matter · Physics 2024-05-24 Ingo Nitschke , Axel Voigt

We perform energy spectrum analysis of the active turbulence in 3D bulk active nematic using continuum numerical modelling. Specifically, we calculate the spectra of two main energy contributions---kinetic energy and nematic elastic…

Soft Condensed Matter · Physics 2020-09-15 Žiga Krajnik , Žiga Kos , Miha Ravnik

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

Active materials are those in which individual, uncoordinated local stresses drive the material out of equilibrium on a global scale. Examples of such assemblies can be seen across scales from schools of fish to the cellular cytoskeleton…

Soft Condensed Matter · Physics 2022-09-30 Nitin Kumar , Rui Zhang , Steven A. Redford , Juan J. de Pablo , Margaret L. Gardel

We study the spatiotemporal patterns that emerge when an active nematic film is topologically constraint. These topological constraints allow to control the non-equilibrium dynamics of the active system. We consider ellipsoidal shapes for…

Soft Condensed Matter · Physics 2017-03-13 Francesco Alaimo , Christian Köhler , Axel Voigt

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 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

There is now growing evidence of the emergence and biological functionality of liquid crystal features, including nematic order and topological defects, in cellular tissues. However, how such features that intrinsically rely on particle…

Soft Condensed Matter · Physics 2019-02-06 Romain Mueller , Julia Yeomans , Amin Doostmohammadi