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arXiv · 1204.2708

Live Soap: Order, Fluctuations and Instabilities in Active Smectics

Tapan Chandra Adhyapak·Sriram Ramaswamy·John Toner
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Abstract

We construct a hydrodynamic theory of noisy, apolar active smectics, in bulk suspension or on a substrate. Our predictions include: quasi-long-ranged smectic order in dimension d = 2, and long- ranged in d = 3, extending previously published results to all dynamical regimes; Kosterlitz-Thouless melting to an active nematic at high and low concentrations in d = 2; nonzero second-sound speed parallel to the layers; the suppression of giant number fluctuations by smectic elasticity; instability to spontaneous undulation and flow in bulk contractile smectics; a layer spacing instability, possibly oscillatory, for large enough extensile active stresses.

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Tapan Chandra Adhyapak, Sriram Ramaswamy, John Toner. 2012-04-12. Live Soap: Order, Fluctuations and Instabilities in Active Smectics. https://doi.org/10.1103/physrevlett.110.118102

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