{
  "annotation_id": "e162b006-da7f-421a-8d22-c1a54fbb7473",
  "date_created": "2026-03-02T18:02:27.229000Z",
  "date_modified": "2026-03-02T18:02:27.229000Z",
  "file_hash": "9bffbf384352d2bf6d1286dbe1749e1ce83d06be4e823dd383a2a97f6c91d184",
  "private": false,
  "record": {
    "abstract": "We have implemented a universal quantum logic gate between qubits stored in\nthe spin state of a pair of trapped calcium 40 ions. An initial product state\nwas driven to a maximally entangled state deterministically, with 83% fidelity.\nWe present a general approach to quantum state tomography which achieves good\nrobustness to experimental noise and drift, and use it to measure the spin\nstate of the ions. We find the entanglement of formation is 0.54.",
    "arxiv_id": "quant-ph/0603273",
    "authors": [
      "J. P. Home",
      "M. J. McDonnell",
      "D. M. Lucas",
      "G. Imreh",
      "B. C. Keitch",
      "D. J. Szwer",
      "N. R. Thomas",
      "S. C. Webster",
      "D. N. Stacey",
      "A. M. Steane"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1088/1367-2630/8/9/188",
    "journal_ref": "New J. Phys. 8 (2006) 188.",
    "title": "Deterministic entanglement and tomography of ion spin qubits",
    "url": "https://arxiv.org/abs/quant-ph/0603273"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "90519049-59d1-45b6-bf5a-fde5d8bb193b",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}