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Thermodynamics of information exchange between two coupled quantum dots
Aki Kutvonen1, Takahiro Sagawa2, Tapio Ala-Nissila1,3
1COMP Center of Excellence, Department of Applied Physics, Aalto University School of Science, P.O. Box 11000, FI-00076 Aalto, Espoo, Finland.
Physical Review. E
|April 15, 2016
Summary
This study introduces a quantum dot system to quantify measurement thermodynamics and operate a Maxwell's demon. The setup demonstrates feedback seemingly violating the second law of thermodynamics, offering insights into information-driven engines.
Area of Science:
- Quantum Thermodynamics
- Mesoscopic Physics
- Information Theory
Background:
- The second law of thermodynamics traditionally limits information extraction from measurements.
- Maxwell's demon thought experiment explores the interplay between information and thermodynamics.
- Quantum systems offer a platform to investigate these fundamental principles at the nanoscale.
Purpose of the Study:
- To quantitatively characterize the thermodynamics of measurement in a quantum system.
- To demonstrate the operation of a Maxwell's demon using coupled quantum dots.
- To derive fluctuation relations for entropy production in a measurement-feedback cycle.
Main Methods:
- Proposing a theoretical setup with two coupled quantum dots.
- Utilizing external parameter control for measurement and feedback operations.
- Analyzing the system at the level of single realizations.
Main Results:
- Quantitative characterization of measurement thermodynamics.
- Demonstration of feedback apparently violating the second law of thermodynamics.
- Derivation of integral fluctuation relations for entropy production.
Conclusions:
- The proposed quantum dot setup serves as a functional Maxwell's demon.
- The study provides a detailed, single-realization explanation of the measurement-feedback cycle.
- The derived fluctuation relations offer new theoretical tools for quantum thermodynamics.
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