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arXiv · 2005.01164

Role of friction in multidefect ordering

Kristian Thijssen·Mehrana R. Nejad·Julia M. Yeomans
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Abstract

We use continuum simulations to study the impact of friction on the ordering of defects in an active nematic. Even in a frictionless system, +1/2 defects tend to align side-by-side and orient antiparallel reflecting their propensity to form, and circulate with, flow vortices. Increasing friction enhances the effectiveness of the defect-defect interactions, and defects form dynamically evolving, large scale, positionally and orientationally-ordered structures which can be explained as a competition between hexagonal packing, preferred by the -1/2 defects, and rectangular packing preferred by the +1/2 defects.

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Kristian Thijssen, Mehrana R. Nejad, Julia M. Yeomans. 2020-05-03. Role of friction in multidefect ordering. https://doi.org/10.1103/physrevlett.125.218004

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