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Initial-state dependence of thermodynamic dissipation for any quantum process.
Paul M Riechers1,2, Mile Gu1,2,3
1Nanyang Quantum Hub, School of Physical and Mathematical Sciences, Nanyang Technological University, 637371, Singapore, Singapore.
Physical Review. E
|May 19, 2021
Summary
Researchers derived exact results for open quantum systems by analyzing initial conditions. System
Area of Science:
- Quantum Physics
- Thermodynamics
- Information Theory
Background:
- Understanding nonequilibrium thermodynamics in open quantum systems is crucial.
- Current models often lack exact results at arbitrary timescales.
Purpose of the Study:
- To derive exact results for nonequilibrium thermodynamics in open quantum systems.
- To establish a connection between system distinguishability and thermodynamic dissipation.
Main Methods:
- Analysis of all possible variations of initial system and environment conditions.
- Development of a quantum-information theoretic equality for entropy production.
- Quantification of thermodynamic dissipation via system's loss of distinction.
Main Results:
- An exact quantum-information theoretic equality for entropy production was obtained, valid for arbitrary initial joint states.
- System's loss of distinction from the minimally dissipative state quantifies thermodynamic dissipation.
- The quantum component of dissipation is identified as the change in coherence relative to the minimally dissipative state.
Conclusions:
- The study provides exact results for open quantum systems thermodynamics.
- Findings have implications for quantum state preparation and local control.
- Mismatched expectations in nonunitary processes can lead to divergent dissipation.
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