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arXiv · 1909.01381

Topological structure and dynamics of three dimensional active nematics

Guillaume Duclos·Raymond Adkins·Debarghya Banerjee·Matthew S. E. Peterson·Minu Varghese·Itamar Kolvin·Arvind Baskaran·Robert A. Pelcovits·Thomas R. Powers·Aparna Baskaran·Federico Toschi·Michael F. Hagan·Sebastian J. Streichan·Vincenzo Vitelli·Daniel A. Beller·Zvonimir Dogic
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Abstract

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 report the creation of three-dimensional active nematics by dispersing extensile microtubule bundles in a passive colloidal liquid crystal. Light-sheet microscopy reveals the millimeter-scale structure of active nematics with a single bundle resolution and the temporal evolution of the associated nematic director field. The dominant excitations of three-dimensional active nematics are extended charge-neutral disclination loops that undergo complex dynamics and recombination events. These studies introduce a new class of non-equilibrium systems whose turbulent-like dynamics arises from the interplay between internally generated active stresses, the chaotic flows and the topological structure of the constituent defects.

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Guillaume Duclos, Raymond Adkins, Debarghya Banerjee, Matthew S. E. Peterson, Minu Varghese, Itamar Kolvin, Arvind Baskaran, Robert A. Pelcovits, Thomas R. Powers, Aparna Baskaran, Federico Toschi, Michael F. Hagan, Sebastian J. Streichan, Vincenzo Vitelli, Daniel A. Beller, Zvonimir Dogic. 2019-09-03. Topological structure and dynamics of three dimensional active nematics. https://doi.org/10.1126/science.aaz4547

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