Measuring entanglement in condensed matter systems.

  title={Measuring entanglement in condensed matter systems.},
  author={Marcus Cramer and Martin Bodo Plenio and Harald Wunderlich},
  journal={Physical review letters},
  volume={106 2},
We show how entanglement may be quantified in spin and cold atom many-body systems using standard experimental techniques only. The scheme requires no assumptions on the state in the laboratory, and a lower bound to the entanglement can be read off directly from the scattering cross section of neutrons deflected from solid state samples or the time-of-flight distribution of cold atoms in optical lattices, respectively. This removes a major obstacle which so far has prevented the direct and… 

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