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Nonequilibrium work and entropy production by quantum projective measurements
1Department of Physics, Pusan National University, Busan 609-735, Korea.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|October 16, 2013
Summary
Quantum projective measurements perform nonequilibrium work, satisfying the Jarzynski equality. Repeated measurements cause unique work behaviors, validating Landauer's principle through entropy changes.
Area of Science:
- Quantum thermodynamics
- Statistical mechanics
- Quantum information theory
Background:
- Quantum projective measurements are fundamental in quantum mechanics.
- Nonequilibrium work and fluctuation theorems are key concepts in statistical mechanics.
- The relationship between quantum measurements and thermodynamic principles requires further investigation.
Purpose of the Study:
- To investigate the thermodynamic implications of quantum projective measurements.
- To analyze the work performed during quantum measurements using fluctuation theorems.
- To explore the connection between quantum measurement effects and fundamental thermodynamic principles like Landauer's principle.
Main Methods:
- Utilizing a framework based on the fluctuation theorem of nonequilibrium work.
- Analyzing the energy changes induced by quantum projective measurements.
- Investigating the effects of repeated measurements and the quantum Zeno effect on work averages.
Main Results:
- Quantum projective measurements were shown to perform nonequilibrium work on the measured system, satisfying the Jarzynski equality.
- The average work exhibits distinct limiting behaviors due to measurement-induced heating and the quantum Zeno effect.
- The entropy increase in a reservoir was proven to be no less than the von Neumann entropy change during measurements, confirming Landauer's principle.
Conclusions:
- Quantum projective measurements can be thermodynamically interpreted as performing nonequilibrium work.
- Measurement-induced effects like heating and the Zeno effect lead to unique thermodynamic behaviors.
- The study provides a theoretical validation of Landauer's principle within the context of quantum measurements.
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