The Squashed Entanglement of a Quantum Channel

@article{Takeoka2014TheSE,
  title={The Squashed Entanglement of a Quantum Channel},
  author={Masahiro Takeoka and Saikat Guha and Mark M. Wilde},
  journal={IEEE Transactions on Information Theory},
  year={2014},
  volume={60},
  pages={4987-4998}
}
This paper defines the squashed entanglement of a quantum channel as the maximum squashed entanglement that can be registered by a sender and receiver at the input and output of a quantum channel, respectively. A new subadditivity inequality for the original squashed entanglement measure of Christandl and Winter leads to the conclusion that the squashed entanglement of a quantum channel is an additive function of a tensor product of any two quantum channels. More importantly, this new… 

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