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Demonstrating Quantum Microscopic Reversibility Using Coherent States of Light
Marco Bellini1,2, Hyukjoon Kwon3, Nicola Biagi1,2
1Istituto Nazionale di Ottica (CNR-INO), Largo Enrico Fermi 6, 50125 Florence, Italy.
Physical Review Letters
|November 4, 2022
Summary
We propose a quantum generalization of microscopic reversibility for fluctuation theorems. Quantum coherence makes backward processes less likely, especially at low temperatures.
Area of Science:
- Thermodynamics
- Quantum Mechanics
- Statistical Physics
Background:
- Microscopic reversibility is fundamental to fluctuation theorems and thermodynamics.
- Quantum systems challenge this principle due to energy uncertainty.
Purpose of the Study:
- To propose and experimentally verify a quantum generalization of microscopic reversibility.
- To investigate the role of quantum coherence in thermodynamic processes.
Main Methods:
- Developed a theoretical framework for quantum microscopic reversibility.
- Experimentally tested the concept using a beam splitter with coherent and thermal optical states.
- Employed heterodyne detection for measurements.
Main Results:
- Demonstrated that quantum coherence influences the likelihood of backward processes.
- Confirmed the quantum modification is significant at low temperatures.
- Observed a quantum-to-classical transition with increasing temperature.
Conclusions:
- The study provides a quantum-corrected understanding of microscopic reversibility.
- Quantum effects are crucial for thermodynamics in the quantum regime.
- Experimental validation confirms theoretical predictions in optical systems.
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