{
  "annotation_id": "6b3488fc-15a0-4253-95fe-41b92577403a",
  "date_created": "2026-03-02T18:02:20.695000Z",
  "date_modified": "2026-03-02T18:02:20.695000Z",
  "file_hash": "bbc8348abb6249d9144dd89c2802e11fe3f6e22fdb3530d86f27369818ee2f49",
  "private": false,
  "record": {
    "abstract": "We propose a new protocol of \\textit{universal} entanglement concentration,\nwhich converts many copies of an \\textit{unknown} pure state to an \\textit{%\nexact} maximally entangled state. The yield of the protocol, which is outputted\nas a classical information, is probabilistic, and achives the entropy rate with\nhigh probability, just as non-universal entanglement concentration protocols\ndo.\n  Our protocol is optimal among all similar protocols in terms of wide\nvarieties of measures either up to higher orders or non-asymptotically,\ndepending on the choice of the measure. The key of the proof of optimality is\nthe following fact, which is a consequence of the symmetry-based construction\nof the protocol: For any invariant measures, optimal protocols are found out in\nmodifications of the protocol only in its classical output, or the claim on the\nproduct.\n  We also observe that the classical part of the output of the protocol gives a\nnatural estimate of the entropy of entanglement, and prove that that estimate\nachieves the better asymptotic performance than any other (potentially global)\nmeasurements.",
    "arxiv_id": "quant-ph/0509140",
    "authors": [
      "Keiji Matsumoto",
      "Masahito Hayashi"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.75.062338",
    "title": "Universal entanglement concentration",
    "url": "https://arxiv.org/abs/quant-ph/0509140"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "7261dd94-84a3-4097-9b8e-fceb407350a2",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}