Detecting nonclassical system-environment correlations by local operations.

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