arXiv:1106.2028 · Physical Review Letters

Behavior of Quantum Correlations under Local Noise

Alexander Streltsov, Hermann Kampermann, Dagmar Bruß

Published Oct 17, 2011• 188 citations

Abstract

We characterize the behavior of quantum correlations under the influence of local noisy channels. Intuition suggests that such noise should be detrimental for quantumness. When considering qubit systems, we show for which channels this is indeed the case: The amount of quantum correlations can only decrease under the action of unital channels. However, nonunital channels (e.g., such as dissipation) can create quantum correlations for some initially classical states. Furthermore, for higher-dimensional systems even unital channels may increase the amount of quantum correlations. Thus, counterintuitively, local decoherence can generate quantum correlations.

DOI: 10.1103/physrevlett.107.170502

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