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arXiv · 1708.03935

Topological edge floppy modes in disordered fiber networks

Di Zhou·Leyou Zhang·Xiaoming Mao
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Abstract

Disordered fiber networks are ubiquitous in a broad range of natural (e.g., cytoskeleton) and manmade (e.g., aerogels) materials. In this paper, we discuss the emergence of topological floppy edge modes in these fiber networks as a result of deformation or active driving. It is known that a network of straight fibers exhibits bulk floppy modes which only bend the fibers without stretching them. We find that, interestingly, with a perturbation in geometry, these bulk modes evolve into edge modes. We introduce a topological index for these edge modes and discuss their implications in biology.

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Di Zhou, Leyou Zhang, Xiaoming Mao. 2017-08-13. Topological edge floppy modes in disordered fiber networks. https://doi.org/10.1103/physrevlett.120.068003

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