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 generalizes 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.
| Translated title of the contribution | Identification Via Quantum Channels in the Presence of Prior Correlation and Feedback |
|---|---|
| Original language | English |
| Title of host publication | General Theory of Information Transfer and Combinatorics |
| Editors | R Ahlswede |
| Publisher | Springer |
| Pages | 486 - 504 |
| Number of pages | 19 |
| ISBN (Print) | 9783540462446 |
| Publication status | Published - 2006 |