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Coherences and the thermodynamic uncertainty relation: Insights from quantum absorption refrigerators
Junjie Liu1, Dvira Segal1,2
1Department of Chemistry and Centre for Quantum Information and Quantum Control, University of Toronto, 80 Saint George Street, Toronto, Ontario, M5S 3H6, Canada.
Physical Review. E
|April 17, 2021
Summary
Quantum coherences enhance heat current noise in thermal machines, confirming the thermodynamic uncertainty relation. This highlights the importance of fluctuations for assessing quantum machine performance.
Area of Science:
- Quantum thermodynamics
- Quantum information science
- Statistical mechanics
Background:
- The thermodynamic uncertainty relation (TUR) links precision and dissipation in classical systems.
- Understanding TUR in quantum regimes is crucial for quantum thermal machines.
- Quantum coherences can significantly impact quantum system dynamics and performance.
Purpose of the Study:
- To investigate the validity of the thermodynamic uncertainty relation in the quantum regime.
- To explore the role of quantum system coherences and heat current fluctuations on TUR.
- To analyze the performance of quantum absorption refrigerators with and without coherence.
Main Methods:
- Full counting statistics simulation of the Redfield quantum master equation.
- Analysis of steady-state quantum absorption refrigerators.
- Comparison of performance in the presence and absence of quantum coherence.
Main Results:
- Quantum coherences enhance the relative noise of cooling power in quantum absorption refrigerators.
- This enhancement corroborates the thermodynamic uncertainty relation in the quantum regime.
- Coherence can either suppress or enhance cooling power compared to the incoherent limit.
Conclusions:
- Quantum system coherences increase heat current fluctuations, validating the thermodynamic uncertainty relation.
- Fluctuations must be considered when evaluating the performance of quantum coherent thermal machines.
- The study provides insights into the fundamental trade-offs governing quantum thermal devices.
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