{
  "annotation_id": "9eadbd21-60fd-4847-91b3-7a75034a7e0c",
  "date_created": "2026-03-02T18:01:42.695000Z",
  "date_modified": "2026-03-02T18:01:42.695000Z",
  "file_hash": "9017d3963c1590fe64421e18921eb7ca90d4b6e7041eefbec02080d0e58be488",
  "private": false,
  "record": {
    "abstract": "Upon entangling a spatial binary alternative of a photon with its\npolarization, one can use single photons to study arbitrary 2-qubit states.\nSending the photon through a Mach-Zehnder interferometer, equipped with sets of\nwave plates that change the polarization, amounts to performing a unitary\ntransformation on the 2-qubit state. We show that any desired unitary gate can\nbe realized by a judicious choice of the parameters of the set-up and discuss a\nnumber of applications. They include the diagnosis of an unknown 2-qubit state,\nan optical Grover search, and the realization of a thought experiment invented\nby Vaidman, Aharonov, and Albert.",
    "arxiv_id": "quant-ph/0101064",
    "authors": [
      "Berthold-Georg Englert",
      "Christian Kurtsiefer",
      "Harald Weinfurter"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.63.032303",
    "journal_ref": "Physical Review A, vol. 63, 2001, art. no. 032303 (10 pages)",
    "title": "Universal unitary gate for single-photon 2-qubit states",
    "url": "https://arxiv.org/abs/quant-ph/0101064"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "e0a225a2-7037-4f4e-a2c4-263d5dfd7a8f",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}