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arXiv · 0806.3265

Energy transport in jammed sphere packings

Ning Xu·Vincenzo Vitelli·Matthieu Wyart·Andrea J. Liu·Sidney R. Nagel
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Abstract

We calculate the normal modes of vibration in jammed sphere packings to obtain the energy diffusivity, a spectral measure of transport. At the boson peak frequency, we find an Ioffe-Regel crossover from a diffusivity that drops rapidly with frequency to one that is nearly frequency-independent. This crossover frequency shifts to zero as the system is decompressed towards the jamming transition, providing unambiguous evidence of a regime in frequency of nearly constant diffusivity. Such a regime, postulated to exist in glasses to explain the temperature dependence of the thermal conductivity, therefore appears to arise from properties of the jamming transition.

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Ning Xu, Vincenzo Vitelli, Matthieu Wyart, Andrea J. Liu, Sidney R. Nagel. 2008-11-17. Energy transport in jammed sphere packings. https://doi.org/10.1103/physrevlett.102.038001

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