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Updated: Aug 3, 2026
11:38
Combining Microfluidics and Microrheology to Determine Rheological Properties of Soft Matter during Repeated Phase Transitions
Published on: April 19, 2018
A two-time-scale, two-temperature scenario for nonlinear rheology
Summary
External forces suppress aging in glassy systems, making them time-invariant. This drive-induced shear thinning and two-temperature behavior offer new insights into jammed matter dynamics.
Area of Science:
- Condensed Matter Physics
- Statistical Mechanics
- Nonlinear Dynamics
Background:
- Glassy and jammed systems typically exhibit aging, where their properties evolve over time.
- External driving forces can alter the equilibrium dynamics of these complex systems.
Purpose of the Study:
- To investigate the effects of external non-conservative forces on glassy/jammed systems.
- To analyze the suppression of aging and changes in correlation/response functions under driving.
Main Methods:
- Utilizing a dynamical closure approximation, exact for disordered, fully connected models.
- Analyzing the dependence of relaxation time and response functions on drive intensity and temperature.
Main Results:
- Demonstrated "shear thinning": relaxation time decreases with increasing drive.
- Observed two-time-scale relaxation in correlation functions below the glass transition temperature (Tc).
- Characterized the violation of the fluctuation-dissipation theorem, revealing a two-temperature regime.
Conclusions:
- External driving can induce time-translation invariance and suppress aging in glassy systems.
- The observed phenomena, like shear thinning and the two-temperature regime, may extend beyond mean-field models.
- Results provide testable predictions for experiments and simulations of driven jammed matter.
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