# Detecting nonclassical system-environment correlations by local operations.

@article{Gessner2011DetectingNS, title={Detecting nonclassical system-environment correlations by local operations.}, author={Manuel Gessner and Heinz-Peter Breuer}, journal={Physical review letters}, year={2011}, volume={107 18}, pages={ 180402 } }

We develop a general strategy for the detection of nonclassical system-environment correlations in the initial states of an open quantum system. The method employs a dephasing map which operates locally on the open system and leads to an experimentally accessible witness for genuine quantum correlations, measuring the Hilbert-Schmidt distance between pairs of open system states. We further derive the expectation value of the witness for various random matrix ensembles modeling generic features…

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