{
  "annotation_id": "f1c1401c-3ce1-47a0-8b7f-ecc39142f5a3",
  "date_created": "2026-03-02T18:02:24.028000Z",
  "date_modified": "2026-03-02T18:02:24.028000Z",
  "file_hash": "30f1b2261dfc3842f35055c0a5e27173c771cecf9f867225dacbc96603b69a38",
  "private": false,
  "record": {
    "abstract": "We discuss the concept of polarization states of four-dimensional quantum\nsystems based on frequency non-degenerate biphoton field. Several quantum\ntomography protocols were developed and implemented for measurement of an\narbitrary state of ququart. A simple method that does not rely on\ninterferometric technique is used to generate and measure the sequence of\nstates that can be used for quantum communication purposes.",
    "arxiv_id": "quant-ph/0602138",
    "authors": [
      "Yu. I. Bogdanov",
      "E. V. Moreva",
      "G. A. Maslennikov",
      "R. F. Galeev",
      "S. S. Straupe",
      "S. P. Kulik"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.73.063810",
    "title": "Polarization ququarts",
    "url": "https://arxiv.org/abs/quant-ph/0602138"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "a70d8f0e-8fbc-4f3f-98fa-b805fea854ef",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}