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DOE OSTI · 1603221

Topological structure and dynamics of three-dimensional active nematics

Duclos, Guillaume (ORCID:0000000190108952)·Adkins, Raymond (ORCID:0000000176222812)·Banerjee, Debarghya·Peterson, Matthew S. E. (ORCID:0000000257497770)·Varghese, Minu (ORCID:0000000344100233)·Kolvin, Itamar (ORCID:0000000268691245)·Baskaran, Arvind·Pelcovits, Robert A. (ORCID:0000000205207516)·Powers, Thomas R. (ORCID:0000000334328226)·Baskaran, Aparna·Toschi, Federico (ORCID:0000000159352332)·Hagan, Michael F. (ORCID:0000000292112434)·Streichan, Sebastian J.·Vitelli, Vincenzo·Beller, Daniel A. (ORCID:000000031957164X)·Dogic, Zvonimir (ORCID:0000000301421838)
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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.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

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Duclos, Guillaume (ORCID:0000000190108952), Adkins, Raymond (ORCID:0000000176222812), Banerjee, Debarghya, Peterson, Matthew S. E. (ORCID:0000000257497770), Varghese, Minu (ORCID:0000000344100233), Kolvin, Itamar (ORCID:0000000268691245), Baskaran, Arvind, Pelcovits, Robert A. (ORCID:0000000205207516), Powers, Thomas R. (ORCID:0000000334328226), Baskaran, Aparna, Toschi, Federico (ORCID:0000000159352332), Hagan, Michael F. (ORCID:0000000292112434), Streichan, Sebastian J., Vitelli, Vincenzo, Beller, Daniel A. (ORCID:000000031957164X), Dogic, Zvonimir (ORCID:0000000301421838). 2020-03-05. Topological structure and dynamics of three-dimensional active nematics. https://doi.org/10.1126/science.aaz4547

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