{
  "annotation_id": "86c12a18-f5c5-4e7d-b84b-bb31a0038b2c",
  "date_created": "2026-03-02T18:02:40.650000Z",
  "date_modified": "2026-03-02T18:02:40.650000Z",
  "file_hash": "25bd54b2250e515b9e6bdb1b50d96cb9e96ebd70811b070e8756d5f5f7f8cfee",
  "private": false,
  "record": {
    "abstract": "We review our recent work on the universal (i.e. input state independent)\noptimal quantum copying (cloning) of qubits. We present unitary transformations\nwhich describe the optimal cloning of a qubit and we present the corresponding\nquantum logical network. We also present network for an optimal quantum copying\n``machine\u0027\u0027 (transformation) which produces N+1 identical copies from the\noriginal qubit. Here again the quality (fidelity) of the copies does not depend\non the state of the original and is only a function of the number of copies, N.\nIn addition, we present the machine which universaly and optimally clones\nstates of quantum objects in arbitrary-dimensional Hilbert spaces. In\nparticular, we discuss universal cloning of quantum registers.",
    "arxiv_id": "quant-ph/9801009",
    "authors": [
      "Vladimir Buzek",
      "Mark Hillery"
    ],
    "categories": [
      "quant-ph"
    ],
    "title": "Universal optimal cloning of qubits and quantum registers",
    "url": "https://arxiv.org/abs/quant-ph/9801009"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "a6a18930-52d6-44b8-88ec-2d6756289057",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}