{
  "annotation_id": "73799609-5e44-429c-9440-b05f70c081b8",
  "date_created": "2026-03-02T18:01:59.868000Z",
  "date_modified": "2026-03-02T18:01:59.868000Z",
  "file_hash": "de09ca3fd57fd88e53d03dfc869581152d7de8fb118667f03f7d6f7a31b9de15",
  "private": false,
  "record": {
    "abstract": "We report our theoretical and experimental investigations into errors in\nquantum state estimation, putting a special emphasis on their asymptotic\nbehavior. Tomographic measurements and maximum likelihood estimation are used\nfor estimating several kinds of identically prepared quantum states (bi-photon\npolarization states) produced via spontaneous parametric down-conversion.\nExcess errors in the estimation procedures are eliminated by introducing a new\nestimation strategy utilizing Akaike\u0027s information criterion. We make a\nquantitative comparision between the errors of the experimentally estimated\nstates and their asymptotic lower bounds, which are derived from the\nCram\\\u0027{e}r-Rao inequality. Our results reveal influence of entanglement on the\nerrors in the estimation. An alternative measurement strategy employing\ninseparable measurements is also discussed, and its performance is numerically\nexplored.",
    "arxiv_id": "quant-ph/0306083",
    "authors": [
      "Koji Usami",
      "Yoshihiro Nambu",
      "Yoshiyuki Tsuda",
      "Keiji Matsumoto",
      "Kazuo Nakamura"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.68.022314",
    "journal_ref": "Phys. Rev. A 68, 022314 (2003)",
    "title": "Accuracy of quantum-state estimation utilizing Akaike\u0027s information   criterion",
    "url": "https://arxiv.org/abs/quant-ph/0306083"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "184ec2e3-24fa-4ba7-b2c8-600d89e0fedb",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}