Quantum and Classical Data Transmission through Completely Depolarizing Channels in a Superposition of Cyclic Orders.

  title={Quantum and Classical Data Transmission through Completely Depolarizing Channels in a Superposition of Cyclic Orders.},
  author={Giulio Chiribella and Matthew Wilson and Hoi Fung Chau},
  journal={Physical review letters},
  volume={127 19},
Completely depolarizing channels are often regarded as the prototype of physical processes that are useless for communication: any message that passes through them along a well-defined trajectory is completely erased. When two such channels are used in a quantum superposition of two alternative orders, they become able to transmit some amount of classical information, but still no quantum information can pass through them. Here, we show that the ability to place N completely depolarizing… Expand

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