Dynamical coexistence in moderately polydisperse hard-sphere glasses

Matteo Campo; Thomas Speck

doi:10.1063/1.5134842

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arXiv · 1910.12045

Dynamical coexistence in moderately polydisperse hard-sphere glasses

Matteo Campo·Thomas Speck

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Abstract

We perform extensive numerical simulations of a paradigmatic model glass former, the hard-sphere fluid with 10% polydispersity. We sample from the ensemble of trajectories with fixed observation time, whereby single trajectories are generated by event-driven molecular dynamics. We show that these trajectories can be characterized in terms of local structure, and we find a dynamical-structural (active-inactive) phase transition between two dynamical phases: one dominated by liquid-like trajectories with low degree of local order and one dominated by glassy-like trajectories with a high degree of local order. We show that both phases coexist and are separated by a spatiotemporal interface. Sampling exceptionally long trajectories allows to perform a systematic finite-size scaling analysis. We find excellent agreement with Binder's scaling theory for first-order transitions. Interestingly, the coexistence region narrows at higher densities, supporting the idea of a critical point controlling the dynamic arrest.

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Matteo Campo, Thomas Speck. 2019-10-26. Dynamical coexistence in moderately polydisperse hard-sphere glasses. https://doi.org/10.1063/1.5134842

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