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Behavior of quantum correlations under local noise
Alexander Streltsov1, Hermann Kampermann, Dagmar Bruss
1Heinrich-Heine-Universität Düsseldorf, Institut für Theoretische Physik III, D-40225 Düsseldorf, Germany. streltsov@thphy.uni-duesseldorf.de
Physical Review Letters
|November 24, 2011
Summary
Local noisy channels can surprisingly generate quantum correlations, even with decoherence. While some noise decreases quantumness in qubit systems, other types, like dissipation, can create it, especially in higher dimensions.
Area of Science:
- Quantum Information Science
- Quantum Computing
- Quantum Physics
Background:
- Quantum correlations are fundamental to quantum information processing.
- Local noisy channels, or decoherence, typically degrade quantum states.
- Understanding noise effects is crucial for robust quantum technologies.
Purpose of the Study:
- To investigate how local noisy channels affect quantum correlations.
- To determine conditions under which quantum correlations can be generated or destroyed.
- To explore the role of system dimensionality and channel type.
Main Methods:
- Analysis of quantum correlation dynamics under various local noisy channels.
- Consideration of both qubit (two-dimensional) and higher-dimensional quantum systems.
- Distinction between unital and nonunital quantum channels, including dissipative processes.
Main Results:
- Unital channels generally decrease quantum correlations in qubit systems.
- Nonunital channels, such as dissipation, can create quantum correlations from classical states.
- Even unital channels can increase quantum correlations in higher-dimensional systems.
Conclusions:
- Local decoherence can unexpectedly generate quantum correlations.
- The impact of noise on quantum correlations is non-trivial and depends on channel properties and system dimension.
- This finding has implications for quantum state preparation and error correction strategies.
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