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Maximally and minimally correlated states attainable within a closed evolving system
Sania Jevtic1, David Jennings, Terry Rudolph
1Controlled Quantum Dynamics Theory, Department of Physics, Imperial College London, London, United Kingdom.
Physical Review Letters
|May 1, 2012
Summary
Correlations in closed quantum systems are limited. This study explores maximizing and minimizing quantum correlations, particularly in quantum thermodynamics, offering solvable methods for two-qubit systems and simplified approaches for larger ones.
Area of Science:
- Quantum Information Theory
- Quantum Thermodynamics
- Quantum Many-Body Systems
Background:
- Quantum correlations are fundamental to quantum mechanics.
- Understanding correlation limits is crucial for quantum information processing and thermodynamics.
- Previous work has explored correlation bounds in various quantum systems.
Purpose of the Study:
- To investigate the constraints on correlations in closed quantum systems.
- To identify methods for finding maximally and minimally correlated states.
- To explore the utility of correlation variation in quantum thermodynamics.
Main Methods:
- Analysis of unitary orbits for quantum states.
- Optimization techniques to find extremal correlation values.
- Specific solutions for two-qubit systems.
- Reduction of larger system problems to classical optimization.
Main Results:
- Established that correlations in closed quantum systems are inherently constrained.
- Developed methods to determine the maximum and minimum attainable correlations.
- Demonstrated the applicability of these methods in quantum thermodynamics.
- Provided a complete solution for two-qubit systems and a tractable approach for larger systems.
Conclusions:
- The study provides a framework for understanding and quantifying correlation limits in closed quantum systems.
- The developed optimization techniques are valuable for quantum thermodynamics and related fields.
- The findings pave the way for more efficient manipulation and utilization of quantum correlations.
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