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arXiv · 1409.0596

Disordered Solids Without Well-Defined Transverse Phonons: The Nature of Hard Sphere Glasses

Xipeng Wang·Wen Zheng·Lijin Wang·Ning Xu
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Abstract

We probe the Ioffe-Regel limits of glasses with repulsions near the zero-temperature jamming transition by measuring the dynamical structure factors. At zero temperature, the transverse Ioffe-Regel frequency vanishes at the jamming transition with a diverging length, but the longitudinal one does not, which excludes the existence of a diverging length associated with the longitudinal excitations. At low temperatures, the transverse and longitudinal Ioffe-Regel frequencies approach zero at the jamming-like transition and glass transition, respectively. As a consequence, glasses between the glass transition and jamming-like transition, which are hard sphere glasses in the low temperature limit, can only carry well-defined longitudinal phonons and have an opposite pressure dependence of the ratio of the shear modulus to the bulk modulus from glasses beyond the jamming-like transition.

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Xipeng Wang, Wen Zheng, Lijin Wang, Ning Xu. 2014-09-28. Disordered Solids Without Well-Defined Transverse Phonons: The Nature of Hard Sphere Glasses. https://doi.org/10.1103/physrevlett.114.035502

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