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Nonequilibrium quantum impurities: from entropy production to information theory
1Department of Molecular Biology , Princeton University, Princeton, New Jersey 08544, USA.
Physical Review Letters
|March 21, 2008
Summary
Nonequilibrium steady states break time-reversal symmetry and produce entropy. This study defines entropy production using thermodynamic arguments, showing it
Area of Science:
- Quantum physics
- Thermodynamics
- Statistical mechanics
Background:
- Nonequilibrium steady-state currents continuously dissipate energy, unlike equilibrium systems.
- This energy dissipation leads to entropy production and breaks time-reversal symmetry.
Purpose of the Study:
- To define and interpret the rate of entropy production in quantum impurity models.
- To demonstrate that entropy production is always positive in nonequilibrium steady states.
Main Methods:
- Utilized simple thermodynamic arguments to define the rate of entropy production (sigma).
- Interpreted sigma using information-theoretic concepts and nonequilibrium distribution functions.
Main Results:
- Established a clear definition for entropy production rate (sigma).
- Showed that sigma has a direct information-theoretic interpretation.
- Demonstrated that entropy production is strictly positive for all nonequilibrium steady states.
Conclusions:
- The study provides a robust framework for understanding entropy production in quantum systems.
- Applied the developed concepts to specific quantum impurity models, including the resonance level and Kondo models.
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