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arXiv · 1606.03353

Strain pattern in supercooled liquids

Bernd Illing·Sebastian Fritschi·David Hajnal·Christian Klix·Peter Keim·Matthias Fuchs
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Abstract

Investigations of strain correlations at the glass transition reveal unexpected phenomena. The shear strain fluctuations show an Eshelby-strain pattern ($\,\sim \cos{(4θ)}/r^2\,$), characteristic for elastic response, even in liquids at long times [1]. We address this using a mode-coupling theory for the strain fluctuations in supercooled liquids and data from both, video microscopy of a two-dimensional colloidal glass former and simulations of Brownian hard disks. We show that long-ranged and long-lived strain-signatures follow a scaling law valid close to the glass transition. For large enough viscosities, the Eshelby-strain pattern is visible even on time scales longer than the structural relaxation time $τ$ and after the shear modulus has relaxed to zero.

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Bernd Illing, Sebastian Fritschi, David Hajnal, Christian Klix, Peter Keim, Matthias Fuchs. 2016-08-05. Strain pattern in supercooled liquids. https://doi.org/10.1103/physrevlett.117.208002

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