Subtleties of witnessing quantum coherence in nonisolated systems

  title={Subtleties of witnessing quantum coherence in nonisolated systems},
  author={George C Knee and Max Marcus and Luke D. Smith and Animesh Datta},
  journal={Physical Review A},
Identifying nonclassicality unambiguously and inexpensively is a long-standing open challenge in physics. The no-signaling-in-time protocol was developed as an experimental test for macroscopic realism, and serves as a witness of quantum coherence in isolated quantum systems by comparing the quantum state to its completely dephased counterpart. We show that it provides a lower bound on a certain resource-theoretic coherence monotone. We go on to generalize the protocol to the case where the… Expand

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