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06:07
Studying Large Amplitude Oscillatory Shear Response of Soft Materials
Published on: April 25, 2019
Unusual response to a localized perturbation in a generalized elastic model
Alessandro Taloni1, Aleksei Chechkin, Joseph Klafter
1School of Chemistry, Tel Aviv University, Tel Aviv 69978, Israel.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 21, 2011
Summary
This study explores how localized forces affect complex physical systems. Unexpected behaviors, like reversed drift and system splitting, emerge under constant or periodic forces, impacting probe dynamics.
Area of Science:
- Physics
- Soft Matter Physics
- Statistical Mechanics
Background:
- Generalized elastic models describe diverse physical systems including polymers, membranes, and interfaces.
- Localized potentials (external forces) applied to single probes are crucial for understanding system responses.
- Fluctuation-dissipation relations provide a framework for analyzing system dynamics under external influences.
Purpose of the Study:
- To derive the fractional Langevin equation for tagged and untagged probes under localized potentials.
- To investigate the physical scenarios arising from constant and time-periodic forces within generalized elastic models.
- To analyze the role of hydrodynamic interactions on probe dynamics.
Main Methods:
- Derivation of the fractional Langevin equation.
- Application of fluctuation-dissipation relations.
- Analysis of short-time dynamics for constant forces.
- Examination of macroscopic effects for time-periodic forces.
Main Results:
- The average drift can be linear, ballistic, or exponential depending on force type and hydrodynamic interactions.
- Drift direction can oppose the external force under specific parameter values.
- Time-periodic forces induce macroscopic spatial splitting of the system into two regions with distinct dynamics.
Conclusions:
- Localized forces can induce counterintuitive dynamics in generalized elastic systems.
- Hydrodynamic interactions significantly influence probe response to external forces.
- Time-periodic forces lead to macroscopic spatial organization and differentiated dynamics within the system.
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