{
  "annotation_id": "d8adcb8d-40b2-480d-9c64-1b05301cf485",
  "date_created": "2026-03-02T18:01:42.361000Z",
  "date_modified": "2026-03-02T18:01:42.361000Z",
  "file_hash": "04e4e6794cdf0d533ed038114907c634ac615db8e0ecba35753b25b15b250787",
  "private": false,
  "record": {
    "abstract": "Double-pair emission from type-II parametric down conversion results in a\nhighly entangled 4-photon state. Due to interference, which is similar to\nbunching from thermal emission, this state is not simply a product of two\npairs. The observation of this state can be achieved by splitting the two\nemission modes at beam splitters and subsequent detection of a photon in each\noutput. Here we describe the features of this state and give a Bell theorem for\na 4-photon test of local realistic hidden variable theories.",
    "arxiv_id": "quant-ph/0103049",
    "authors": [
      "Harald Weinfurter",
      "Marek Zukowski"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.64.010102",
    "title": "Four Photon Entanglement from Down Conversion",
    "url": "https://arxiv.org/abs/quant-ph/0103049"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "6aab8ef8-f34e-44a8-8dfb-119eecc39ed3",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}