Error Thresholds for Arbitrary Pauli Noise

  title={Error Thresholds for Arbitrary Pauli Noise},
  author={Johannes Bausch and Felix Leditzky},
The error threshold of a one-parameter family of quantum channels is defined as the largest noise level such that the quantum capacity of the channel remains positive. This in turn guarantees the existence of a quantum error correction code for noise modeled by that channel. Discretizing the single-qubit errors leads to the important family of Pauli quantum channels; curiously, multipartite entangled states can increase the threshold of these channels beyond the so-called hashing bound, an… 

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