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Studying Large Amplitude Oscillatory Shear Response of Soft Materials
Published on: April 25, 2019
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Effective temperature of active fluids and sheared soft glassy materials
1Department of Chemical and Biological Physics, The Weizmann Institute of Science, 76100, Rehovot, Israel.
The European Physical Journal. E, Soft Matter
|October 11, 2018
Summary
This study unifies the description of dynamics in active systems by showing effective temperatures from simulations match analytical models for single active particles in viscoelastic fluids.
Area of Science:
- Non-equilibrium physics
- Soft glassy materials
- Active matter physics
Background:
- Active fluids and soft glassy materials exhibit complex dynamics driven by internal particle activity or external shearing.
- Non-equilibrium motion in these systems is often quantified using effective temperatures derived from kinetic energy and fluctuation-dissipation relations.
Purpose of the Study:
- To demonstrate that effective temperatures from many-body simulations of active systems align with analytical models.
- To propose a unified framework for understanding dynamics in diverse active systems.
Main Methods:
- Utilizing many-body simulations to track passive tracer particle motion in active fluids.
- Analyzing systems driven by boundary shearing in soft glassy materials.
- Calculating effective temperatures from tracer kinetic energy and fluctuation-dissipation relations.
Main Results:
- Effective temperatures extracted from simulations of active fluids and sheared soft glassy materials conform to analytical expressions.
- Analytical expressions derived for a single active particle in a viscoelastic fluid accurately describe simulation results.
Conclusions:
- A unified description for the dynamics within active systems is suggested.
- The findings provide testable predictions for future experimental and theoretical studies in non-equilibrium physics.
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