English

Identification via Quantum Channels in the Presence of Prior Correlation and Feedback

Quantum Physics 2017-08-01 v4

Abstract

Continuing our earlier work (quant-ph/0401060), we give two alternative proofs of the result that a noiseless qubit channel has identification capacity 2: the first is direct by a "maximal code with random extension" argument, the second is by showing that 1 bit of entanglement (which can be generated by transmitting 1 qubit) and negligible (quantum) communication has identification capacity 2. This generalises a random hashing construction of Ahlswede and Dueck: that 1 shared random bit together with negligible communication has identification capacity 1. We then apply these results to prove capacity formulas for various quantum feedback channels: passive classical feedback for quantum-classical channels, a feedback model for classical-quantum channels, and "coherent feedback" for general channels.

Keywords

Cite

@article{arxiv.quant-ph/0403203,
  title  = {Identification via Quantum Channels in the Presence of Prior Correlation and Feedback},
  author = {Andreas Winter},
  journal= {arXiv preprint arXiv:quant-ph/0403203},
  year   = {2017}
}

Comments

19 pages. Requires Rinton-P9x6.cls. v2 has some minor errors/typoes corrected and the claims of remark 22 toned down (proofs are not so easy after all). v3 has references to simultaneous ID coding removed: there were necessary changes in quant-ph/0401060. v4 (final form) has minor corrections