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Quantum Coherences and Classical Inhomogeneities as Equivalent Thermodynamics Resources
Andrew Smith1, Kanupriya Sinha2,3, Christopher Jarzynski1,4,5
1Department of Physics, University of Maryland, College Park, MD 20742, USA.
Entropy (Basel, Switzerland)
|April 23, 2022
Summary
Quantum energy coherences are a thermodynamic resource. However, classical systems possess analogous energy-shell inhomogeneities that yield equal work in the semiclassical limit, negating a unique quantum advantage.
Area of Science:
- Thermodynamics
- Quantum Mechanics
- Statistical Mechanics
Background:
- Quantum energy coherences are recognized as a thermodynamic resource.
- Exploiting these coherences allows for energy extraction from thermal reservoirs to perform work.
- Classical systems may possess analogous resources for work extraction.
Purpose of the Study:
- To investigate the existence and properties of classical thermodynamic resources analogous to quantum coherences.
- To compare the work-extracting potential of quantum coherences with classical energy-shell inhomogeneities.
- To determine if quantum coherences offer a unique thermodynamic advantage over classical systems.
Main Methods:
- Theoretical comparison of work extraction from quantum coherences and classical phase space inhomogeneities.
- Analysis in the semiclassical limit to establish a correspondence between quantum and classical systems.
- Utilizing concepts from statistical mechanics and quantum thermodynamics.
Main Results:
- Identified energy-shell inhomogeneities in classical phase space distributions as a thermodynamic resource analogous to quantum coherences.
- Quantitatively compared the work obtainable from both quantum coherences and classical inhomogeneities.
- Found the amount of work extractable to be equal in the semiclassical limit.
Conclusions:
- Quantum coherences do not offer a unique thermodynamic advantage over classical energy-shell inhomogeneities in the semiclassical limit.
- The work-extracting potential is equivalent when a clear semiclassical correspondence exists.
- This suggests that classical systems can harness thermodynamic resources comparable to quantum systems.
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