{
  "annotation_id": "304ea145-8142-41b8-810e-5f10c3d69639",
  "date_created": "2026-03-02T18:02:27.554000Z",
  "date_modified": "2026-03-02T18:02:27.554000Z",
  "file_hash": "a24893ede8f235d5eed368335bcaa400ac1d37522cfcbf609984a3aacca421b6",
  "private": false,
  "record": {
    "abstract": "Interferometry with NOON quantum states can provide unbiased phase estimation\nwith a sensitivity scaling as $\\Delta \\theta \\sim 1/N_T$ given a prior\nknowledge that the true phase shift $\\theta$ lies in the interval $-\\pi \\leq\n\\theta \\leq \\pi$. The protocol requires a total of $N_T = 2^{p}-1$ particles\n(unequally) distributed among $p$ independent measurements and overcomes basic\ndifficulties present in previously proposed approaches. We demonstrate the\npossibility to obtain a phase sensitivity beating the classical shot-noise\nlimit using published probabilities retrieved experimentally for the creation\nof Schr\\\"odinger cat quantum states containing up to N=6 beryllium ions.",
    "arxiv_id": "quant-ph/0606221",
    "authors": [
      "Luca Pezz\u00e9",
      "Augusto Smerzi"
    ],
    "categories": [
      "quant-ph",
      "cond-mat.other"
    ],
    "doi": "10.1209/0295-5075/78/30004",
    "journal_ref": "Europhysics Letters 78, 30004 (2007)",
    "title": "Sub Shot-Noise interferometric phase sensitivity with Beryllium ions   Schroedinger Cat States",
    "url": "https://arxiv.org/abs/quant-ph/0606221"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "a16a13b2-b33b-45b4-886e-7c10609336a8",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}