

Preprint 22/2012
Asymptotic analysis of mode-coupling theory of active nonlinear microrheology
Manuel Gnann and Thomas Voigtmann
Contact the author: Please use for correspondence this email.
Submission date: 10. Apr. 2012 (revised version: April 2012)
Pages: 19
published in: Physical review / E, 86 (2012) 1, art-no. 011406
DOI number (of the published article): 10.1103/PhysRevE.86.011406
Bibtex
PACS-Numbers: 82.70.-y, 64.70.pv, 83.10.-y
Keywords and phrases: Colloidal dispersions, suspensions, and aggregates
Download full preprint: PDF (1547 kB)
Abstract:
We discuss a schematic model of mode-coupling theory for force-driven active nonlinear microrheology,
where a single probe particle is pulled by a constant external force through a dense host
medium. The model exhibits both a glass transition for the host, and a force-induced delocalization
transition, where an initially localized probe inside the glassy host attains a nonvanishing steadystate
velocity by locally melting the glass. Asymptotic expressions for the transient correlation
functions of the schematic model are derived, valid close to the transition points. There appear
several nontrivial time scales relevant for the decay laws of the correlator. For the nonlinear friction
coecient of the probe, the asymptotic expressions give rise to two-parameter scaling laws.