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Related Experiment Video

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Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators

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Published on: May 30, 2014

Einstein-Podolsky-Rosen paradox implies a minimum achievable temperature.

David M Rogers¹

¹Department of Chemistry, University of South Florida, Tampa, Florida 33620, USA.

Physical Review. E

|February 18, 2017

Summary

This study introduces new definitions for heat and work in quantum systems, crucial for understanding thermodynamics under feedback control. These definitions, based on environmental interactions and measurement outcomes, satisfy the second law and reveal a minimum achievable temperature.

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Area of Science:

Quantum Thermodynamics
Statistical Mechanics
Quantum Information

Background:

Understanding thermodynamic laws in quantum systems is challenging due to measurement back-action.
Existing definitions of heat and work often rely on idealized or unobservable system states.

Purpose of the Study:

To develop observational definitions of heat and work for quantum systems under feedback control.
To explore the thermodynamic consequences of repeated partial projection measurements.
To establish a lower bound for entropy production and investigate minimum achievable temperatures.

Main Methods:

Utilizing a repeated partial projection model for quantum systems coupled to environments.
Defining heat and work based solely on environmental properties and measurement outcomes.
Analyzing the master equation approximation at finite measurement rates.

Main Results:

Introduced new, experimentally realizable definitions of heat and work consistent with thermodynamic laws.
Demonstrated that measurement back-action must be classified as work to satisfy the second law.
Derived a formula for the minimum temperature achievable in repeatedly measured quantum systems.

Conclusions:

The proposed definitions offer a consistent framework for quantum thermodynamics under realistic measurement conditions.
The minimum temperature phenomenon has implications for quantum computing purity and experimental tests of fluctuation theorems.