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arXiv · 1209.1108

Slow dynamics in cylindrically confined colloidal suspensions

Nabiha Saklayen·Gary L. Hunter·Kazem V. Edmond·Eric R. Weeks
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Abstract

We study bidisperse colloidal suspensions confined within glass microcapillary tubes to model the glass transition in confined cylindrical geometries. We use high speed three-dimensional confocal microscopy to observe particle motions for a wide range of volume fractions and tube radii. Holding volume fraction constant, we find that particles move slower in thinner tubes. The tube walls induce a gradient in particle mobility: particles move substantially slower near the walls. This suggests that the confinement-induced glassiness may be due to an interfacial effect.

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Nabiha Saklayen, Gary L. Hunter, Kazem V. Edmond, Eric R. Weeks. 2012-09-05. Slow dynamics in cylindrically confined colloidal suspensions. https://doi.org/10.1063/1.4794593

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