“Squashed entanglement”: An additive entanglement measure

  title={“Squashed entanglement”: An additive entanglement measure},
  author={Matthias Christandl and Andreas J. Winter},
  journal={Journal of Mathematical Physics},
In this paper, we present a new entanglement monotone for bipartite quantum states. Its definition is inspired by the so-called intrinsic information of classical cryptography and is given by the halved minimum quantum conditional mutual information over all tripartite state extensions. We derive certain properties of the new measure which we call “squashed entanglement”: it is a lower bound on entanglement of formation and an upper bound on distillable entanglement. Furthermore, it is convex… Expand

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