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arXiv · 1704.00900

Instabilities of jammed packings of frictionless spheres under compression

Ning Xu·Andrea J. Liu·Sidney R. Nagel
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Abstract

We consider the contribution to the density of vibrational states and the distribution of energy barrier heights of incipient instabilities in a glass modeled by a jammed packing of spheres. On approaching an instability, the frequency of a normal mode and the height of the energy barrier to cross into a new ground state both vanish. These instabilities produce a contribution to the density of vibrational states that scales as $ω^3$ at low frequencies $ω$, but which vanishes in the thermodynamic limit. In addition, they affect an anharmonic property, the distribution of energy barriers $ΔH$, giving a contribution that scales as $ΔH^{-1/3}$ at low barrier heights, which should be universal for jammed and glassy systems.

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Ning Xu, Andrea J. Liu, Sidney R. Nagel. 2017-04-04. Instabilities of jammed packings of frictionless spheres under compression. https://doi.org/10.1103/physrevlett.119.215502

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