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arXiv · 0802.3124

Glassy dynamics in monodisperse hard ellipsoids

Patrick Pfleiderer·Kristina Milinkovic·Tanja Schilling
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Abstract

We present evidence from computer simulations for glassy dynamics in suspensions of monodisperse hard ellipsoids. In equilibrium, almost spherical ellipsoids show a first order transition from an isotropic phase to a rotator phase. When overcompressing the isotropic phase into the rotator regime, we observe super-Arrhenius slowing down of diffusion and relaxation, accompanied by two-step relaxation in positional and orientational correlators. The effects are strong enough for asymptotic laws of mode-coupling theory to apply. Glassy dynamics are unusual in monodisperse systems. Typically, polydispersity in size or a mixture of particle species is prerequisite to prevent crystallization. Here, we show that a slight particle anisometry acts as a sufficient source of disorder. This sheds new light on the question of which ingredients are required for glass formation.

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Patrick Pfleiderer, Kristina Milinkovic, Tanja Schilling. 2008-05-08. Glassy dynamics in monodisperse hard ellipsoids. https://doi.org/10.1209/0295-5075/84/16003

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