Heterogeneity and Low-Frequency Vibrations in Bidisperse Sphere Packings

Yusuke Hara; Hideyuki Mizuno; Atsushi Ikeda

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arXiv · 2311.09509

Heterogeneity and Low-Frequency Vibrations in Bidisperse Sphere Packings

Yusuke Hara·Hideyuki Mizuno·Atsushi Ikeda

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Abstract

In the jamming transition of monodisperse packings, spatial heterogeneity is irrelevant as the transition is described by mean-field theories. Here, we show that this situation drastically changes if the particle-size dispersity is large enough. We use computer simulations to study the structural and vibrational properties of bidisperse sphere packings with a large size ratio. Near the critical point, the small particles tend to form clusters, leading to the emergence of large-scale structural heterogeneity. Concomitantly, the low-frequency vibrations are significantly enhanced compared to those in monodisperse packings, and their density of states follows a linear law with the frequency. We numerically and theoretically demonstrate that these behaviors of the structural heterogeneity and the low-frequency vibrations are intimately connected. The present work suggests that the nature of heterogeneous packings is markedly different from that of homogeneous packings.

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Yusuke Hara, Hideyuki Mizuno, Atsushi Ikeda. 2023-11-16. Heterogeneity and Low-Frequency Vibrations in Bidisperse Sphere Packings. https://arxiv.org/abs/2311.09509

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