Trade-off capacities of the quantum Hadamard channels

  title={Trade-off capacities of the quantum Hadamard channels},
  author={Kamil Bradler and Patrick M. Hayden and Dave Touchette and Mark M. Wilde},
Coding theorems in quantum Shannon theory express the ultimate rates at which a sender can transmit information over a noisy quantum channel. More often than not, the known formulas expressing these transmission rates are intractable, requiring an optimization over an infinite number of uses of the channel. Researchers have rarely found quantum channels with a tractable classical or quantum capacity, but when such a finding occurs, it demonstrates a complete understanding of that channel's… 

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