Asymmetric exclusion processes with constrained dynamics.
1The Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, 34100 Trieste, Italy.
Physical Review Letters
|September 4, 2008
Summary
Asymmetric exclusion processes reveal complex behaviors in athermal systems driven by nonconservative forces. These systems exhibit rheological properties, negative differential resistance, and potential jamming transitions at high densities.
Area of Science:
- Statistical mechanics
- Condensed matter physics
Background:
- Athermal systems lack thermal fluctuations.
- Nonconservative forces drive system dynamics.
Purpose of the Study:
- Investigate nonconservative driving forces in athermal systems.
- Introduce asymmetric exclusion processes with locally reversible kinetic constraints.
Main Methods:
- Asymmetric exclusion processes
- Locally reversible kinetic constraints
Main Results:
- High-density systems show rheological-like behavior.
- Observed negative differential resistance and two-step relaxation.
- Dynamical heterogeneity and potential jamming transitions identified.
Conclusions:
- Asymmetric exclusion processes model complex driven systems.
- Nonconservative forces induce rich emergent phenomena.
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