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Macroscopic Thermodynamic Reversibility in Quantum Many-Body Systems
Philippe Faist1,2,3, Takahiro Sagawa4, Kohtaro Kato1
1Institute for Quantum Information and Matter, California Institute of Technology, Pasadena, California 91125, USA.
Physical Review Letters
|January 11, 2020
Summary
This study shows that spatially ergodic states in translation-invariant systems can be reversibly converted to thermal states using thermal operations and coherence. This links abstract thermodynamics to realistic physical systems.
Area of Science:
- Quantum Thermodynamics
- Statistical Mechanics
- Information Theory
Background:
- The resource theory of thermal operations extends equilibrium thermodynamics to non-equilibrium systems.
- Understanding non-equilibrium states and their relation to thermal equilibrium is crucial for thermodynamics.
- Previous models often focused on equilibrium or specific non-equilibrium scenarios.
Purpose of the Study:
- To identify and characterize states in translation-invariant lattice systems that can be reversibly converted to thermal states.
- To establish a link between abstract resource theories and realistic physical systems.
- To provide an operational characterization of thermodynamic potentials in such systems.
Main Methods:
- Utilizing the resource theory of thermal operations.
- Analyzing translation-invariant states on lattices with local Hamiltonians.
- Applying concepts from information theory, including relative entropy and quantum versions of classical theorems.
- Investigating spatially ergodic states and their mixtures.
Main Results:
- Identified spatially ergodic states and their mixtures as convertible to thermal states with limited coherence.
- Demonstrated that states with small relative entropy gaps to the thermal state can be approximately converted.
- Provided quantum analogues of the Shannon-McMillan-Breiman theorem and Stein's lemma.
- Established a robust link between resource theory and physical systems.
Conclusions:
- Spatially ergodic states serve as a resource for generating thermal states in translation-invariant systems.
- The findings offer a practical method for understanding and manipulating non-equilibrium thermodynamics.
- This work bridges theoretical concepts in quantum thermodynamics with observable phenomena in physical systems.
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