{
  "annotation_id": "ed6b7810-3ac3-4972-9db3-4fbe55e5756d",
  "date_created": "2026-03-02T18:02:13.338000Z",
  "date_modified": "2026-03-02T18:02:13.338000Z",
  "file_hash": "674540ad96efe7c9172faad9e942706afcd1ac632447db154c0d1c13e8a90816",
  "private": false,
  "record": {
    "abstract": "Making use of exact results and quantum Monte Carlo data for the entanglement\nof formation, we show that the ground state of anisotropic two-dimensional\nS=1/2 antiferromagnets in a uniform field takes the classical-like form of a\nproduct state for a particular value and orientation of the field, at which the\npurely quantum correlations due to entanglement disappear. Analytical\nexpressions for the energy and the form of such states are given, and a novel\ntype of exactly solvable two-dimensional quantum models is therefore singled\nout. Moreover, we show that the field-induced quantum phase transition present\nin the models is unambiguously characterized by a cusp minimum in the\npairwise-to-global entanglement ratio R, marking the quantum-critical\nenhancement of \\emph{multipartite} entanglement. A detailed discussion is\nprovided on the universality of the cusp in R as a signature of quantum\ncritical behavior entirely based on entanglement.",
    "arxiv_id": "quant-ph/0412098",
    "authors": [
      "Tommaso Roscilde",
      "Paola Verrucchi",
      "Andrea Fubini",
      "Stephan Haas",
      "Valerio Tognetti"
    ],
    "categories": [
      "quant-ph",
      "cond-mat.str-el"
    ],
    "doi": "10.1103/PhysRevLett.94.147208",
    "journal_ref": "Phys. Rev. Lett. 94, 147208 (2005)",
    "title": "Entanglement and factorized ground states in two-dimensional quantum   antiferromagnets",
    "url": "https://arxiv.org/abs/quant-ph/0412098"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "6360dfed-03d4-4f38-8ab6-2e3c0f27fc19",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}