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arXiv · 0804.2060

A minimal model for kinetic arrest

Prasanta Pal·Corey S. O'Hern·Jerzy Blawzdziewicz·Robin Stinchcombe
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Abstract

To elucidate slow dynamics in glassy materials, we introduce the {\it Figure-8 model} in which $N$ hard blocks undergo Brownian motion around a circuit in the shape of a figure-8. This system undergoes kinetic arrest at a critical packing fraction $ϕ=ϕ_g < 1$, and for $ϕ\approxϕ_g$ long-time diffusion is controlled by rare, cooperative `junction-crossing' particle rearrangements. We find that the average time between junction crossings $τ_{JC}$, and hence the structural relaxation time, does not simply scale with the configurational volume $\OmegaLow$ of transition states, because $τ_{JC}$ also depends on the time to complete a junction crossing. The importance of these results in understanding cage-breaking dynamics in glassy systems is discussed.

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Prasanta Pal, Corey S. O'Hern, Jerzy Blawzdziewicz, Robin Stinchcombe. 2008-04-13. A minimal model for kinetic arrest. https://doi.org/10.1103/physreve.78.011111

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