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arXiv · 1010.2899

Schematic Models for Active Nonlinear Microrheology

Manuel V. Gnann·Igor Gazuz·Antonio M. Puertas·Matthias Fuchs·Thomas Voigtmann
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Abstract

We analyze the nonlinear active microrheology of dense colloidal suspensions using a schematic model of mode-coupling theory. The model describes the strongly nonlinear behavior of the microscopic friction coefficient as a function of applied external force in terms of a delocalization transition. To probe this regime, we have performed Brownian dynamics simulations of a system of quasi-hard spheres. We also analyze experimental data on hard-sphere-like colloidal suspensions [Habdas et al., Europhys. Lett., 2004, 67, 477]. The behavior at very large forces is addressed specifically.

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Manuel V. Gnann, Igor Gazuz, Antonio M. Puertas, Matthias Fuchs, Thomas Voigtmann. 2010-10-14. Schematic Models for Active Nonlinear Microrheology. https://doi.org/10.1039/c0sm00828a

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