{
  "annotation_id": "65e50907-4fa3-4e14-abf5-395ab82f43f6",
  "date_created": "2026-03-02T18:02:20.707000Z",
  "date_modified": "2026-03-02T18:02:20.707000Z",
  "file_hash": "801cd5dd25f601d585d9e38ecd8f9fe00c37712909ba051d51370efab7300166",
  "private": false,
  "record": {
    "abstract": "We investigate how equilibrium entanglement is manifested in the nonlinear\nresponse of an $N$-qubit system. We show that in the thermodynamic limit the\nirreducible part of the $n$th-order nonlinear susceptibility indicates that the\neigenstates of the system contain entangled $(n+1)$-qubit clusters. This opens\nthe way to a directly observable multiqubit entanglement signature. We show\nthat the irreducible part of the static cubic susceptibility of a system of\nfour flux qubits, as a function of external parameters, behaves as a global\n4-qubit entanglement measure introduced in Ref.\\cite{Love}.\n  We discuss the possibility of extracting purely-entanglement-generated\ncontribution from the general multipoint correlators in a multiqubit system.",
    "arxiv_id": "quant-ph/0510154",
    "authors": [
      "A. M. Zagoskin",
      "A. Yu. Smirnov",
      "S. K. Gupta",
      "I. S. Slobodov"
    ],
    "categories": [
      "quant-ph",
      "cond-mat.other"
    ],
    "title": "Nonlinear response and observable signatures of equilibrium entanglement",
    "url": "https://arxiv.org/abs/quant-ph/0510154"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "ad9ab742-e2ad-4758-80e4-7f26a10795e1",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}