Measuring entanglement entropy of a generic many-body system with a quantum switch.

  title={Measuring entanglement entropy of a generic many-body system with a quantum switch.},
  author={Dmitry A. Abanin and Eugene A. Demler},
  journal={Physical review letters},
  volume={109 2},
Entanglement entropy has become an important theoretical concept in condensed matter physics because it provides a unique tool for characterizing quantum mechanical many-body phases and new kinds of quantum order. However, the experimental measurement of entanglement entropy in a many-body system is widely believed to be unfeasible, owing to the nonlocal character of this quantity. Here, we propose a general method to measure the entanglement entropy. The method is based on a quantum switch (a… 

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