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arXiv · 2112.11693

Emergent Chirality and Current Generation

Satyanu Bhadra·Shankar Ghosh·Shamik Gupta
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Abstract

We investigate the phenomenon of producing vibration-induced rotational motion in a cylinder filled with achiral rods and being vibrated by an external drive. The arrangement of the rods develops chirality as a result of the interaction of gravity and steric hindrance, which is responsible for the induced motion. A two-rod arrangement is sufficient to generate a persistent motion. The average angular velocity $\langle \omega \rangle$ of the rods at long times varies non-monotonically with the packing fraction $\phi$ for a given drive strength $\Gamma$. Though the precise nature of the variation of $\langle \omega \rangle$ with $\phi$ depends on the details of the interaction between individual rods, its general characteristics hold true for rods of various materials and geometries. A stochastic model based on the asymmetric simple exclusion process helps in understanding the key features of our experiments.

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Satyanu Bhadra, Shankar Ghosh, Shamik Gupta. 2021-12-22. Emergent Chirality and Current Generation. https://doi.org/10.1103/physrevresearch.3.043179

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