{
  "annotation_id": "c2d7bd36-a4d4-4d51-abb9-92fc91ac2ea7",
  "date_created": "2026-03-02T18:02:45.074000Z",
  "date_modified": "2026-03-02T18:02:45.074000Z",
  "file_hash": "26edf153d3e5b59b13fa4b86e990b62ef2e56339f7cf927ceb3fdf40e13f63d8",
  "private": false,
  "record": {
    "abstract": "The state of the signal-idler photon pair of spontaneous parametric down\nconversion(SPDC) is a typical nonlocal entangled pure state with zero entropy.\nThe precise correlation of the subsystems is completely described by the state.\nHowever, it is an experimental choice to study only one subsystem and to ignore\nthe other. What can we learn about the measured subsystem and the remaining\nparts? Results of this kind of measurements look peculiar. The experiment\nconfirms that the two subsystems are both in mixed states with entropy greater\nthan zero. One can only obtain statistical knowledge of the subsystems in this\nkind of measurement.",
    "arxiv_id": "quant-ph/9811060",
    "authors": [
      "Dmitry V. Strekalov",
      "Yoon-Ho Kim",
      "Yanhua Shih"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.60.2685",
    "journal_ref": "Phys.Rev. A60 (1999) 2685",
    "title": "Experimental study of a photon as a subsystem of an entangled two-photon   state",
    "url": "https://arxiv.org/abs/quant-ph/9811060"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "256a73a1-3390-4024-ab39-51576117b8a6",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}