{
  "annotation_id": "f2eb824d-3aa0-423d-971c-8f6bd2aa679b",
  "date_created": "2026-03-02T18:02:20.581000Z",
  "date_modified": "2026-03-02T18:02:20.581000Z",
  "file_hash": "e194247b178d75006804d671c18ae262c6a666c5ab7dbabfe37b42e52131e49a",
  "private": false,
  "record": {
    "abstract": "The thermal entanglement in a two-spin-qutrit system with two spins coupled\nby exchange interaction under a magnetic field in an arbitrary direction is\ninvestigated. Negativity, the measurement of entanglement, is calculated. We\nfind that for any temperature the evolvement of negativity is symmetric with\nrespect to magnetic field. The behavior of negativity is presented for four\ndifferent cases. The results show that for different temperature, different\nmagnetic field give maximum entanglement. Both the parallel and antiparallel\nmagnetic field cases are investigated qualitatively (not quantitatively) in\ndetail, we find that the entanglement may be enhanced under an antiparallel\nmagnetic field.",
    "arxiv_id": "quant-ph/0509014",
    "authors": [
      "Guo-Feng Zhang",
      "Shu-Shen Li"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1140/epjd/e2005-00235-1",
    "journal_ref": "Eur. Phys. J. D 37,123-127 (2006)",
    "title": "Thermal entanglement in a two-spin-qutrit system under a nonuniform   external magnetic field",
    "url": "https://arxiv.org/abs/quant-ph/0509014"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "2d26cac9-e5b6-420a-aef7-0c2dfde877d4",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}