{
  "annotation_id": "eef78290-7558-4245-97ae-add35cc5becc",
  "date_created": "2026-03-02T18:02:06.996000Z",
  "date_modified": "2026-03-02T18:02:06.996000Z",
  "file_hash": "ad51f05ba9a0ca2b2f191f1bfcb12e91de2e3d50745b6318b4803526f3b05ebf",
  "private": false,
  "record": {
    "abstract": "We study the degree to which quantum entanglement survives when a three-qubit\nentangled state is copied by using local and non-local processes, respectively,\nand investigate iterating quantum copying for the three-qubit system. There may\nexist inter-three-qubit entanglement and inter-two-qubit entanglement for the\nthree-qubit system. We show that both local and non-local copying processes\ndegrade quantum entanglement in the three-particle system due to a residual\ncorrelation between the copied output and the copying machine. We also show\nthat the inter-two-qubit entanglement is preserved better than the\ninter-three-qubit entanglement in the local cloning process. We find that\nnon-local cloning is much more efficient than the local copying for\nbroadcasting entanglement, and output state via non-local cloning exhibits the\nfidelity better than local cloning.",
    "arxiv_id": "quant-ph/0402074",
    "authors": [
      "Zhao-Yang Tong",
      "Le-Man Kuang"
    ],
    "categories": [
      "quant-ph"
    ],
    "journal_ref": "Commun. Theor. Phys. 38 (2002) 541-546",
    "title": "Entanglement Preserving in Quantum Copying of Three-qubit Entangled   State",
    "url": "https://arxiv.org/abs/quant-ph/0402074"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "d48f6014-2a51-4405-a70c-b53792bfb002",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}