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Quantum Work Statistics with Initial Coherence
María García Díaz1, Giacomo Guarnieri2, Mauro Paternostro3
1Física Teòrica: Informació i Fenòmens Quàntics, Departament de Física, Universitat Autònoma de Barcelona, ES-08193 Bellaterra (Barcelona), Spain.
Entropy (Basel, Switzerland)
|December 8, 2020
Summary
The Margenau-Hill scheme allows for non-equilibrium initial states in thermodynamic work calculations, unlike the standard two-point measurement scheme. Differences in work moments and entropy production are linked to initial state coherence.
Area of Science:
- Quantum Thermodynamics
- Statistical Mechanics
Background:
- The two-point measurement scheme for thermodynamic work requires initial equilibrium.
- The Margenau-Hill scheme extends this to non-equilibrium initial states.
Purpose of the Study:
- To quantitatively compare the two-point measurement and Margenau-Hill schemes.
- To analyze the role of initial state coherence in thermodynamic work calculations.
Main Methods:
- Utilizing the l1-coherence measure to quantify initial state coherence.
- Comparing work moments (first moments, variances) and average entropy production between schemes.
Main Results:
- Differences in work moments and average entropy production are functions of initial coherence.
- Average entropy production can yield negative values within the Margenau-Hill framework.
Conclusions:
- Initial state coherence is a key factor differentiating thermodynamic work calculations in equilibrium and non-equilibrium scenarios.
- The Margenau-Hill scheme offers a broader framework for studying thermodynamic processes, including potential for negative entropy production.
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