{
  "annotation_id": "9c55ba24-243c-4b5a-bbb7-ecd243914b4f",
  "date_created": "2026-03-02T18:02:34.491000Z",
  "date_modified": "2026-03-02T18:02:34.491000Z",
  "file_hash": "c9a42eea98498fd35a30b72f15a60192ed8a883f659ae20dfe513a6c678b76cb",
  "private": false,
  "record": {
    "abstract": "We extend to finite temperature the fidelity approach to quantum phase\ntransitions (QPTs). This is done by resorting to the notion of mixed-state\nfidelity that allows one to compare two density matrices corresponding to two\ndifferent thermal states. By exploiting the same concept we also propose a\nfinite-temperature generalization of the Loschmidt echo. Explicit analytical\nexpressions of these quantities are given for a class of quasi-free fermionic\nHamiltonians. A numerical analysis is performed as well showing that the\nassociated QPTs show their signatures in a finite range of temperatures.",
    "arxiv_id": "quant-ph/0612008",
    "authors": [
      "Paolo Zanardi",
      "H. T. Quan",
      "Xiaoguang Wang",
      "C. P. Sun"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.75.032109",
    "journal_ref": "Phys. Rev. A 75, 032109 (2007)",
    "title": "Mixed-state fidelity and quantum criticality at finite temperature",
    "url": "https://arxiv.org/abs/quant-ph/0612008"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "ee025bc4-7ef3-4094-a301-1b09afbb41b4",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}