Dephrasure Channel and Superadditivity of Coherent Information.

@article{Leditzky2018DephrasureCA,
  title={Dephrasure Channel and Superadditivity of Coherent Information.},
  author={Felix Leditzky and Debbie W. Leung and Graeme Smith},
  journal={Physical review letters},
  year={2018},
  volume={121 16},
  pages={
          160501
        }
}
The quantum capacity of a quantum channel captures its capability for noiseless quantum communication. It lies at the heart of quantum information theory. Unfortunately, our poor understanding of nonadditivity of coherent information makes it hard to understand the quantum capacity of all but very special channels. In this Letter, we consider the dephrasure channel, which is the concatenation of a dephasing channel and an erasure channel. This very simple channel displays remarkably rich and… 
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