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Generalized energy measurements and modified transient quantum fluctuation theorems.
Gentaro Watanabe1, B Prasanna Venkatesh2, Peter Talkner3
1Asia Pacific Center for Theoretical Physics (APCTP), San 31, Hyoja-dong, Nam-gu, Pohang, Gyeongbuk 790-784, Korea and Department of Physics, POSTECH, San 31, Hyoja-dong, Nam-gu, Pohang, Gyeongbuk 790-784, Korea.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|October 30, 2014
Summary
Researchers show how generalized energy measurements can determine work statistics in quantum systems, enabling modified transient fluctuation relations even with experimental measurement errors. This work simplifies experimental quantum thermodynamics.
Area of Science:
- Quantum thermodynamics
- Statistical mechanics
- Experimental physics
Background:
- Accurate work determination is vital for transient fluctuation relations in quantum systems.
- Projective energy measurements are theoretically preferred but experimentally challenging.
- Generalized measurements offer a potential alternative for work statistics determination.
Purpose of the Study:
- To demonstrate a method for calculating work statistics using generalized energy measurements.
- To establish modified transient fluctuation relations applicable to experimental quantum systems.
- To analyze the impact of measurement errors on work statistics and fluctuation relations.
Main Methods:
- Utilizing generalized energy measurements instead of projective measurements.
- Deriving a relationship between work statistics from generalized and projective measurements.
- Investigating modified versions of the Crooks relation and Jarzynski equality.
Main Results:
- Work statistics from generalized measurements are simply related to those from projective measurements.
- Modified transient fluctuation relations arise due to generalized measurement errors.
- Gaussian energy measurements yield particularly simple expressions for modified relations.
- Repeated generalized measurements approximate projective measurements via the central limit theorem.
Conclusions:
- Generalized energy measurements provide a viable experimental route to study transient fluctuation relations.
- Measurement errors introduce universal modifications to fluctuation relations, dependent only on error characteristics.
- The proposed method offers a practical approach to quantum thermodynamics experiments, overcoming limitations of projective measurements.
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