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Published on: March 30, 2017
Anomalous diffusion of driven particles in supercooled liquids
Carsten F E Schroer1, Andreas Heuer
1Institut für physikalische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 28/30, 48149 Münster, Germany. c.schroer@uni-muenster.de
Physical Review Letters
|February 26, 2013
Summary
Simulations reveal superdiffusive behavior and giant diffusivity in tagged particles under external force. These findings, explained by continuous time random walk, link nonequilibrium superdiffusivity to equilibrium non-Gaussian parameters.
Area of Science:
- Statistical Mechanics
- Condensed Matter Physics
- Computational Physics
Background:
- Understanding particle dynamics in complex fluids is crucial.
- Nonequilibrium systems exhibit unique transport properties.
- Lennard-Jones mixtures are standard models for studying fluid behavior.
Purpose of the Study:
- To investigate the diffusive properties of a tagged particle in a binary Lennard-Jones mixture under an external force.
- To quantitatively describe the observed superdiffusive behavior.
- To establish a connection between nonequilibrium dynamics and equilibrium properties.
Main Methods:
- Nonequilibrium dynamics simulations.
- Application of an external force on a single tagged particle.
- Continuous time random walk (CTRW) analysis in configuration space.
Main Results:
- Observed superdiffusive behavior at intermediate times for the tagged particle's diffusion parallel to the applied force.
- Detected giant long-time diffusivity.
- Provided a quantitative description of these phenomena using CTRW analysis.
- Demonstrated that the physical properties causing superdiffusivity in nonequilibrium systems also govern the non-Gaussian parameter in equilibrium systems.
Conclusions:
- The study elucidates the complex diffusive behavior of tagged particles in driven systems.
- CTRW analysis provides a robust framework for describing anomalous transport.
- A fundamental link exists between transport properties in equilibrium and nonequilibrium states.
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