English

Probabilistic cloning with supplementary information

Quantum Physics 2009-11-11 v2

Abstract

We consider probabilistic cloning of a state chosen from a mutually nonorthogonal set of pure states, with the help of a party holding supplementary information in the form of pure states. When the number of states is 2, we show that the best efficiency of producing m copies is always achieved by a two-step protocol in which the helping party first attempts to produce m-1 copies from the supplementary state, and if it fails, then the original state is used to produce m copies. On the other hand, when the number of states exceeds two, the best efficiency is not always achieved by such a protocol. We give examples in which the best efficiency is not achieved even if we allow any amount of one-way classical communication from the helping party.

Keywords

Cite

@article{arxiv.quant-ph/0505207,
  title  = {Probabilistic cloning with supplementary information},
  author = {Koji Azuma and Junichi Shimamura and Masato Koashi and Nobuyuki Imoto},
  journal= {arXiv preprint arXiv:quant-ph/0505207},
  year   = {2009}
}

Comments

6 pages, no figures