{
  "annotation_id": "2889b77f-dc73-4f30-8c52-6e52302b8e3d",
  "date_created": "2026-03-02T18:02:13.738000Z",
  "date_modified": "2026-03-02T18:02:13.738000Z",
  "file_hash": "4ac719aac4afd18d2f310edf025d3a97f7e07d2be521a96b4c99360ca99fd522",
  "private": false,
  "record": {
    "abstract": "We investigate the problem of copying pure two-qubit states of a given degree\nof entanglement in an optimal way. Completely positive covariant quantum\noperations are constructed which maximize the fidelity of the output states\nwith respect to two separable copies. These optimal copying processes hint at\nthe intricate relationship between fundamental laws of quantum theory and\nentanglement.",
    "arxiv_id": "quant-ph/0411105",
    "authors": [
      "J. Novotny",
      "G. Alber",
      "I. Jex"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.71.042332",
    "title": "Optimal copying of entangled two-qubit states",
    "url": "https://arxiv.org/abs/quant-ph/0411105"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "1f089ae9-1021-495d-af24-dd4004e3944c",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}