{
  "annotation_id": "02b56a95-a105-41e8-a09d-e5f97ccfed0c",
  "date_created": "2026-03-02T18:02:23.713000Z",
  "date_modified": "2026-03-02T18:02:23.713000Z",
  "file_hash": "2b81c5890f64fec3478d783472d789b08e9cf33b8cb970ad7a710e206765432b",
  "private": false,
  "record": {
    "abstract": "We construct a projection measurement process for the maximally entangled\nN-photon state (the NOON-state) with only linear optical elements and\nphotodetectors. This measurement process will give null result for any N-photon\nstate that is orthogonal to the NOON state. We examine the projection process\nin more detail for N=4 by applying it to a four-photon state from type-II\nparametric down-conversion. This demonstrates an orthogonal projection\nmeasurement with a null result. This null result corresponds to a dip in a\ngeneralized Hong-Ou-Mandel interferometer for four photons. We find that the\ndepth of the dip in this arrangement can be used to distinguish a genuine\nentangled four-photon state from two separate pairs of photons. We next apply\nthe NOON state projection measurement to a four-photon superposition state from\ntwo perpendicularly oriented type-I parametric down-conversion processes. A\nsuccessful NOON state projection is demonstrated with the appearance of the\nfour-photon de Broglie wavelength in the interference fringe pattern.",
    "arxiv_id": "quant-ph/0511189",
    "authors": [
      "F. W. Sun",
      "Z. Y. Ou",
      "G. C. Guo"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.73.023808",
    "title": "Projection Measurement of the Maximally Entangled N-Photon State for a   Demonstration of N-Photon de Broglie Wavelength",
    "url": "https://arxiv.org/abs/quant-ph/0511189"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "97027bcb-2836-40e4-8fa6-7ac99dfe8423",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}