{
  "annotation_id": "a3b44557-4965-4042-8ab4-cfa84186787e",
  "date_created": "2026-03-02T18:02:30.990000Z",
  "date_modified": "2026-03-02T18:02:30.990000Z",
  "file_hash": "a4cc4de558d97eaeb4a105baf9deb9180b862330be5310dbfe6cbdc8da4efae6",
  "private": false,
  "record": {
    "abstract": "There exists an increasing evidence supporting the picture of the Josephson\njunction (JJ) as a \"macroscopic quantum system\". On the other hand the\ninterpretation of experimental data strongly depends on the assumed theoretical\nmodel. We analyse the possible states of a Cooper pair box (\"charge qubit\") for\nthe two types of models : two-mode Bose-Hubbard model with its large $N$\naproximations and the many-body description within the mean-field approximation\n(Gross-Pitaevski equation). While the first class of models supports the\npicture of JJ being a quantum subsystem of a single degree of freedom, the\nsecond approach yields an essentially classical structure of accessible quantum\nstates which, in particular, implies the absence of entanglement for two\ncoupled JJ\u0027s. The arguments in favor of the mean-field theory are presented and\ndifferent experimental tests including a new proposal are briefly discussed.",
    "arxiv_id": "quant-ph/0610008",
    "authors": [
      "Robert Alicki"
    ],
    "categories": [
      "quant-ph"
    ],
    "title": "Quantumness of Josephson junctions reexamined",
    "url": "https://arxiv.org/abs/quant-ph/0610008"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "deedef4c-bf95-4542-8870-14bb18a56766",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}