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Updated: Jun 8, 2026
06:07
Studying Large Amplitude Oscillatory Shear Response of Soft Materials
Published on: April 25, 2019
From equilibrium to steady-state dynamics after switch-on of shear
Matthias Krüger1, Fabian Weysser, Thomas Voigtmann
1Fachbereich Physik, Universität Konstanz, 78457 Konstanz, Germany.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 28, 2010
Summary
Researchers explored the relationship between equilibrium and steady-state dynamics in dense glass-forming liquids under shear flow. They found that applying shear significantly speeds up relaxation, with their theory accurately predicting simulation results.
Area of Science:
- Condensed Matter Physics
- Soft Matter Physics
- Statistical Mechanics
Background:
- Dense glass-forming liquids exhibit slow relaxation dynamics near the glass transition.
- Under steady shear flow, these systems can display shear thinning, a significant acceleration of relaxation.
- Understanding the relationship between equilibrium and non-equilibrium dynamics is crucial for characterizing glassy materials.
Purpose of the Study:
- To investigate the connection between equilibrium, steady-state, and waiting-time-dependent correlation functions in sheared glass-forming liquids.
- To derive and test an approximate relation for these dynamics using the integration through transients (ITT) approach.
- To compare theoretical predictions with results from computer simulations of dense liquids.
Main Methods:
- Development of an approximate relation based on the integration through transients (ITT) approach for nonequilibrium Smoluchowski dynamics.
- Application of the derived relation within a schematic model in the framework of Mode-Coupling Theory (MCT).
- Analysis of computer simulation data from 2D hard-disk and 3D soft-sphere systems, comparing correlation functions with theoretical predictions.
Main Results:
- The study found good qualitative and semiquantitative agreement between the ITT-based approximation and simulation results.
- Excellent quantitative agreement was observed for short waiting times, validating the theoretical approximation.
- For intermediate waiting times, simulations and theory both showed faster decay of correlation functions at long times compared to stationary ones.
Conclusions:
- The ITT-based approximation accurately describes the waiting-time dependence of correlation functions in sheared glass-forming liquids.
- The findings confirm the accuracy of approximations used in deriving fluctuation-dissipation ratios in non-equilibrium systems.
- The study provides a theoretical framework for understanding shear-induced dynamics and relaxation in dense glassy materials.
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