{
  "id": "quant-ph/0306078",
  "version": "v1",
  "published": "2003-06-11T15:27:12.000Z",
  "updated": "2003-06-11T15:27:12.000Z",
  "title": "Distillation of secret key and entanglement from quantum states",
  "authors": [
    "Igor Devetak",
    "Andreas Winter"
  ],
  "comment": "17 pages LaTeX, 1 drawing (eps)",
  "journal": "Proc. R. Soc. Lond. A, vol 461, pp 207--235, 2005.",
  "doi": "10.1098/rspa.2004.1372",
  "categories": [
    "quant-ph"
  ],
  "abstract": "We study and solve the problem of distilling secret key from quantum states representing correlation between two parties (Alice and Bob) and an eavesdropper (Eve) via one-way public discussion: we prove a coding theorem to achieve the \"wire-tapper\" bound, the difference of the mutual information Alice-Bob and that of Alice-Eve, for so-called cqq-correlations, via one-way public communication. This result yields information--theoretic formulas for the distillable secret key, giving ``ultimate'' key rate bounds if Eve is assumed to possess a purification of Alice and Bob's joint state. Specialising our protocol somewhat and making it coherent leads us to a protocol of entanglement distillation via one-way LOCC (local operations and classical communication) which is asymptotically optimal: in fact we prove the so-called \"hashing inequality\" which says that the coherent information (i.e., the negative conditional von Neumann entropy) is an achievable EPR rate. This result is well--known to imply a whole set of distillation and capacity formulas which we briefly review.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2003-06-11T15:27:12.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "distillation",
      "entanglement",
      "negative conditional von neumann entropy",
      "result yields information-theoretic formulas",
      "bobs joint state"
    ],
    "tags": [
      "journal article"
    ],
    "note": {
      "typesetting": "LaTeX",
      "pages": 17,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}