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arXiv · 1305.3047

Single particle fluctuations and directional correlations in driven hard sphere glasses

Suvendu Mandal·Vijaykumar Chikkadi·Bernard Nienhuis·Dierk Raabe·Peter Schall·Fathollah Varnik
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Abstract

Via event driven molecular dynamics simulations and experiments, we study the packing fraction and shear-rate dependence of single particle fluctuations and dynamic correlations in hard sphere glasses under shear. At packing fractions above the glass transition, correlations increase as shear rate decreases: the exponential tail in the distribution of single particle jumps broadens and dynamic four-point correlations increase. Interestingly, however, upon decreasing the packing fraction, a broadening of the exponential tail is also observed, while dynamic heterogeneity is shown to decrease. An explanation for this behavior is proposed in terms of a competition between shear and thermal fluctuations. Building upon our previous studies [Chikkadi et al, Europhys. Lett. (2012)], we further address the issue of anisotropy of the dynamic correlations.

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Suvendu Mandal, Vijaykumar Chikkadi, Bernard Nienhuis, Dierk Raabe, Peter Schall, Fathollah Varnik. 2013-05-14. Single particle fluctuations and directional correlations in driven hard sphere glasses. https://doi.org/10.1103/physreve.88.022129

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