Topological structure and dynamics of three-dimensional active nematics

Science, vol. 367, pp. 1120–1124

Abstract

Topological structures are effective descriptors of the nonequilibrium dynamics of diverse many-body systems. For example, motile, point-like topological defects capture the salient features of two-dimensional active liquid crystals composed of energy-consuming anisotropic units. We dispersed force-generating microtubule bundles in a passive colloidal liquid crystal to form a three-dimensional active nematic. Light-sheet microscopy revealed the temporal evolution of the millimeter-scale structure of these active nematics with single-bundle resolution. The primary topological excitations are extended, charge-neutral disclination loops that undergo complex dynamics and recombination events. Our work suggests a framework for analyzing the nonequilibrium dynamics of bulk anisotropic systems as diverse as driven complex fluids, active metamaterials, biological tissues, and collections of robots or organisms.

Authors 2

1. Guillaume Duclos corresponding

   Brandeis University

   Affiliation as printed

   Department of Physics, Brandeis University, Waltham, MA 02453, USA

2. Sebastian J. Streichan

   University of California, Santa Barbara

   Affiliation as printed

   Department of Physics, University of California, Santa Barbara, CA 93111, USA