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Title: Confinement Controls the Bend Instability of Three-Dimensional Active Liquid Crystals
Spontaneous growth of long-wavelength deformations is a defining feature of active liquid crystals. We investigate the effect of confinement on the instability of 3D active liquid crystals in the isotropic phase composed of extensile microtubule bundles and kinesin molecular motors. When shear aligned, such fluids exhibit finite-wavelength self-amplifying bend deformations. By systematically changing the channel size we elucidate how the instability wavelength and its growth rate depend on the channel dimensions. Experimental findings are qualitatively consistent with a minimal hydrodynamic model, where the fastest growing deformation is set by a balance of active driving and elastic relaxation. Our results demonstrate that confinement determines the structure and dynamics of active fluids on all experimentally accessible length scales.  more » « less
Award ID(s):
2011846
PAR ID:
10506760
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
American Physical Society
Date Published:
Journal Name:
Physical Review Letters
Volume:
125
Issue:
25
ISSN:
0031-9007
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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