{
  "annotation_id": "dbb882b3-1559-4402-9be7-d157fc0fc4cb",
  "date_created": "2026-03-02T18:02:27.663000Z",
  "date_modified": "2026-03-02T18:02:27.663000Z",
  "file_hash": "617a6ede35bd12273a7a47ee012d291595a3e6069dab71053e79c662970a23e0",
  "private": false,
  "record": {
    "abstract": "Not all unitary operations upon a set of qubits can be implemented by\nsequential interactions between each qubit and an ancillary system. We analyze\nthe specific case of sequential quantum cloning 1-\u003eM and prove that the minimal\ndimension D of the ancilla grows linearly with the number of clones M. In\nparticular, we obtain D = 2M for symmetric universal quantum cloning and D =\nM+1 for symmetric phase-covariant cloning. Furthermore, we provide a recipe for\nthe required ancilla-qubit interactions in each step of the sequential\nprocedure for both cases.",
    "arxiv_id": "quant-ph/0607105",
    "authors": [
      "Y. Delgado",
      "L. Lamata",
      "J. Leon",
      "D. Salgado",
      "E. Solano"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevLett.98.150502",
    "journal_ref": "Phys. Rev. Lett. 98, 150502 (2007).",
    "title": "Sequential Quantum Cloning",
    "url": "https://arxiv.org/abs/quant-ph/0607105"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "6f137597-5163-49e7-a428-b95d03b1b1bd",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}