• Corpus ID: 4852725

Correcting quantum channels by measuring the environment

  title={Correcting quantum channels by measuring the environment},
  author={Patrick M. Hayden and Christopher King},
  journal={Quantum Inf. Comput.},
  • P. Hayden, C. King
  • Published 3 September 2004
  • Computer Science
  • Quantum Inf. Comput.
The corrected capacity of a quantum channel is defined as the best one-shot capacity that can be obtained by measuring the environment and using the result to correct the output of the channel. It is shown that (i) all qubit channels have corrected capacity log 2, (ii) a product of N qubit channels has corrected capacity N log 2, and (iii) all channels have corrected capacity at least log 2. The question is posed of finding the channel with smallest corrected capacity in any dimension d. 
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