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Unexpected Density Fluctuations in Jammed Disordered Sphere Packings

A. Donev·F. H. Stillinger·S. Torquato
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Abstract

We computationally study jammed disordered hard-sphere packings as large as a million particles. We show that the packings are saturated and hyperuniform, i.e., that local density fluctuations grow only as a logarithmically-augmented surface area rather than the volume of the window. The structure factor shows an unusual non-analytic linear dependence near the origin, $S(k)\sim|k|$. In addition to exponentially damped oscillations seen in liquids, this implies a weak power-law tail in the total correlation function, $h(r)\sim-r^{-4}$, and a long-ranged direct correlation function.

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A. Donev, F. H. Stillinger, S. Torquato. 2005-06-16. Unexpected Density Fluctuations in Jammed Disordered Sphere Packings. https://doi.org/10.1103/physrevlett.95.090604

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