{
  "annotation_id": "9819f0f3-9297-4c22-bed1-c158fe7f6e39",
  "date_created": "2026-03-02T18:02:00.162000Z",
  "date_modified": "2026-03-02T18:02:00.162000Z",
  "file_hash": "4f20d5d749accb1a9397be36fc6183c5741914d7228afd0b5b96644a6589dd14",
  "private": false,
  "record": {
    "abstract": "We introduce a measure Q of the \"quality\" of a quantum which-way detector,\nwhich characterizes its intrinsic ability to extract which-way information in\nan asymmetric two-way interferometer. The \"quality\" Q allows one to separate\nthe contribution to the distinguishability of the ways arising from the quantum\nproperties of the detector from the contribution stemming from a-priori\nwhich-way knowledge available to the experimenter, which can be quantified by a\npredictability parameter P. We provide an inequality relating these two sources\nof which-way information to the value of the fringe visibility displayed by the\ninterferometer. We show that this inequality is an expression of duality,\nallowing one to trace the loss of coherence to the two reservoirs of which-way\ninformation represented by Q and P. Finally, we illustrate the formalism with\nthe use of a quantum logic gate: the Symmetric Quanton-Detecton System (SQDS).\nThe SQDS can be regarded as two qubits trying to acquire which way information\nabout each other. The SQDS will provide an illustrating example of the\nreciprocal effects induced by duality between system and which-way detector.",
    "arxiv_id": "quant-ph/0306057",
    "authors": [
      "Jesus Martinez-Linares",
      "David Harmin"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.69.062109",
    "title": "Quality of a Which-Way Detector",
    "url": "https://arxiv.org/abs/quant-ph/0306057"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "cb220748-4b4b-49e4-8526-8831cb01ee67",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}