{
  "annotation_id": "42bda2f7-f5e5-4231-a5c0-80b25e01391f",
  "date_created": "2026-03-02T18:01:59.750000Z",
  "date_modified": "2026-03-02T18:01:59.750000Z",
  "file_hash": "fef2c3757d87f417cbb025fa4ba89ce183f4dee75c9f3bea37a1593b1aece557",
  "private": false,
  "record": {
    "abstract": "We present a derivation of the Von Neumann entropy and mutual information of\narbitrary two--mode Gaussian states, based on the explicit determination of the\nsymplectic eigenvalues of a generic covariance matrix. The key role of the\nsymplectic invariants in such a determination is pointed out. We show that the\nVon Neumann entropy depends on two symplectic invariants, while the purity (or\nthe linear entropy) is determined by only one invariant, so that the two\nquantities provide two different hierarchies of mixed Gaussian states. A\ncomparison between mutual information and entanglement of formation for\nsymmetric states is considered, remarking the crucial role of the symplectic\neigenvalues in qualifying and quantifying the correlations present in a generic\nstate.",
    "arxiv_id": "quant-ph/0307073",
    "authors": [
      "Alessio Serafini",
      "Fabrizio Illuminati",
      "Silvio De Siena"
    ],
    "categories": [
      "quant-ph",
      "cond-mat",
      "hep-th",
      "math-ph",
      "math.MP"
    ],
    "doi": "10.1088/0953-4075/37/2/L02",
    "journal_ref": "J. Phys. B 37, L21 (2004)",
    "title": "Symplectic invariants, entropic measures and correlations of Gaussian   states",
    "url": "https://arxiv.org/abs/quant-ph/0307073"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "7359b88b-0fd9-4772-8387-4f0bd180311f",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}