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arXiv · 2411.03667

Crystalline and polycrystalline regimes in a periodically sheared 2-dimensional system of disks

Siyuan Su·Jie Zhang·Charles Radin·Harry L. Swinney
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Abstract

A layer of monodisperse circular steel disks in a nearly square horizontal cell forms, for shear amplitudes SA $\le$ 0.08, hexagonal close-packed crystallites that grow and merge until a single crystal fills the container. Increasing the shear amplitude leads to another reproducible regime, 0.21 $\le$ SA $\le$ 0.27, where a few large polycrystallites grow, shrink, and rotate with shear cycling, but do not evolve into a single crystal that fills the container. These results are robust within certain ranges of applied pressure and shear frequency.

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Siyuan Su, Jie Zhang, Charles Radin, Harry L. Swinney. 2024-11-06. Crystalline and polycrystalline regimes in a periodically sheared 2-dimensional system of disks. https://arxiv.org/abs/2411.03667

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