English
Related papers

Related papers: Defect Spirograph: Dynamical Behavior of Defects i…

200 papers

In this work we present the first systematic framework to sculpt active nematics systems, using optimal control theory and a hydrodynamic model of active nematics. We demonstrate the use of two different control fields, (1) applied…

Soft Condensed Matter · Physics 2020-10-28 Michael M. Norton , Piyush Grover , Michael F. Hagan , Seth Fraden

Topological defects, which are singular points in a director field, play a major role in shaping active systems. Here, we experimentally study topological defects and the flow patterns around them, that are formed during the highly rapid…

Soft Condensed Matter · Physics 2024-03-20 Victor Yashunsky , Daniel J. G. Pearce , Gil Ariel , Avraham Be'er

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

Active nematics are an important new paradigm in soft condensed matter systems. They consist of rod-like components with an internal driving force pushing them out of equilibrium. The resulting fluid motion exhibits chaotic advection, in…

We study the defect dynamics in a colloidal spin ice system realized by filling a square lattice of topographic double well islands with repulsively interacting magnetic colloids. We focus on the contraction of defects in the ground state,…

Soft Condensed Matter · Physics 2016-12-26 Johannes Loehr , Antonio Ortiz-Ambriz , Pietro Tierno

I put forward a continuum theory for active nematic gels, defined as fluids or suspensions of orientable rodlike objects endowed with active dynamics, that is based on symmetry arguments and compatibility with thermodynamics. The starting…

Soft Condensed Matter · Physics 2017-11-15 Stefano S Turzi

Confinement can be used to systematically tame turbulent dynamics occurring in active fluids. Although periodic channels are the simplest geometries to study confinement numerically, the corresponding experimental realizations require…

Soft Condensed Matter · Physics 2023-04-12 Chaitanya Joshi , Zahra Zarei , Michael M. Norton , Seth Fraden , Aparna Baskaran , Michael F. Hagan

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 provide a comprehensive quantitative analysis of localized and extended topological defects in the steady state of 2D passive and active repulsive Brownian disk systems. We show that, both in and out-of-equilibrium, the passage from the…

Morphodynamic equations governing the behaviour of active nematic fluids on deformable curved surfaces are constructed in the large deformation limit. Emphasis is placed on the formulation of objective rates that account for normal…

Soft Condensed Matter · Physics 2023-02-22 Sami C. Al-Izzi , Richard G. Morris

Topological defects are singularities within a field that cannot be removed by continuous transformations. The definition of these irregularities requires an ordered reference configuration, calling into question whether they exist in…

Soft Condensed Matter · Physics 2025-01-06 Vinay Vaibhav , Arabinda Bera , Amelia C. Y. Liu , Matteo Baggioli , Peter Keim , Alessio Zaccone

Drops of active liquid crystal have recently shown the ability to self-propel, which was associated with topological defects in the orientation of active filaments [Sanchez {\em et al.}, Nature {\bf 491}, 431 (2013)]. Here, we study the…

Soft Condensed Matter · Physics 2016-07-05 Diana Khoromskaia , Gareth P. Alexander

We consider a microscopic field theoretical approach for interacting active nematic particles. With only steric interactions the self-propulsion strength in such systems can lead to different collective behaviour, e.g., synchronized…

Soft Condensed Matter · Physics 2021-02-04 Veit Krause , Axel Voigt

Recent experimental realizations of liquid-liquid phase separation of active liquid crystals have offered an insight into the interaction between phase separation, ubiquitous in soft matter and biology, and chaotic active flows. In this…

Soft Condensed Matter · Physics 2025-04-23 Paarth Gulati , Fernando Caballero , M. Cristina Marchetti

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

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…

We develop a formal analogy between configurational stresses in two distinct physical systems, and study the flows that they induce when the configurations of interest include topological de- fects. The two systems in question are…

Soft Condensed Matter · Physics 2018-03-23 Christopher Conklin , Jorge Vinals , Oriol T. Valls

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

Using particle-resolved molecular-dynamics simulations, we compute the phase diagram for soft repulsive spherocylinders confined on the surface of a sphere. While crystal (K), smectic (Sm), and isotropic (I) phases exhibit a stability…

Soft Condensed Matter · Physics 2025-11-03 Jaydeep Mandal , Hartmut Löwen , Prabal K. Maiti

Stabilizing defects in liquid-crystal systems is crucial for many physical processes and applications ranging from functionalizing liquid-crystal textures to recently reported command of chaotic behaviors of active matters. In this work, we…

Soft Condensed Matter · Physics 2017-06-29 Xiuqing Duan , Zhenwei Yao