{
  "annotation_id": "25ad7362-0560-4fdf-b637-f74e24e61ca7",
  "date_created": "2026-03-02T18:02:17.154000Z",
  "date_modified": "2026-03-02T18:02:17.154000Z",
  "file_hash": "d37d15dcd6a4c070fe922e37c0985e88cefb91ba6e1d5341445bb6f7761f6148",
  "private": false,
  "record": {
    "abstract": "Using tools of quantum information theory we show that the ground state of\nthe Dicke model exhibits an infinite sequence of instabilities\n(quantum-phase-like transitions). These transitions are characterized by abrupt\nchanges of the bi-partite entanglement between atoms at critical values\n$\\kappa_j$ of the atom-field coupling parameter $\\kappa$ and are accompanied by\ndiscontinuities of the first derivative of the energy of the ground state. We\nshow that in a weak-coupling limit ($\\kappa_1\\leq \\kappa \\leq \\kappa_2$) the\nCoffman-Kundu-Wootters (CKW) inequalities are saturated which proves that for\nthese values of the coupling no intrinsic multipartite entanglement (neither\namong the atoms nor between the atoms and the field) is generated by the\natom-field interaction. We analyze also the atom-field entanglement and we show\nthat in the strong-coupling limit the field is entangled with the atoms so that\nthe von Neumann entropy of the atomic sample (that serves as a measure of the\natom-field entanglement) takes the value $S_A={1/2}\\ln (N+1)$. The entangling\ninteraction with atoms leads to a highly sub-Poissonian photon statistics of\nthe field mode.",
    "arxiv_id": "quant-ph/0503195",
    "authors": [
      "Vladimir Buzek",
      "Miguel Orszag",
      "Marian Rosko"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevLett.94.163601",
    "title": "Instability and entanglement of the ground state of the Dicke model",
    "url": "https://arxiv.org/abs/quant-ph/0503195"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "b966312f-14a1-4381-8583-ae54848f49dd",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}