Probing the shear viscosity of an active nematic

Abstract

In vitro reconstituted active systems, such as the ATP-driven microtubule bundle suspension developed by the Dogic group, provide a fertile testing ground for elucidating the phenomenology of active liquid crystalline states. Controlling such novel phases of matter crucially depends on our knowledge of their material and physical properties. In this letter, we show that the rheological properties of an active nematic film can be probed by varying its hydrodynamic coupling to a bounding oil layer. Using the motion of disclinations as intrinsic tracers of the flow field and a hydrodynamic model, we obtain an estimate for the as of now unknown shear viscosity of the nematic film. Knowing this now provides us with an additional handle for robust and precision tunable control of the emergent dynamics of active fluids.

5 pages, 4 figures, a SI file, and a SI video

References in corpus (10)

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Cited by in corpus (7)

• Data-driven quantitative modeling of bacterial active nematics
• Probing active nematics with in-situ microfabricated elastic inclusions
• Vortex Lattices in Active Nematics with Periodic Obstacle Arrays
• Vorticity phase separation and defect lattices in the isotropic phase of active liquid crystals
• Friction mediated phase transition in confined active nematics
• Flow patterns and defect dynamics of active nematics under an electric field
• Passive defect driven morphogenesis in nematic membranes