{
  "annotation_id": "c3a6df43-2823-4bfc-ad3d-5d86a793355f",
  "date_created": "2026-03-02T18:02:10.186000Z",
  "date_modified": "2026-03-02T18:02:10.186000Z",
  "file_hash": "0eddab38202abddbb479b46038440478500e0d8a65796c8db9d101b71478bd50",
  "private": false,
  "record": {
    "abstract": "We investigate the ground state and the thermal entanglement in the two-qubit\nIsing model interacting with a site-dependent magnetic field. The degree of\nentanglement is measured by calculating the concurrence. For zero temperature\nand for certain direction of the applied magnetic field, the quantum phase\ntransition observed under a uniform external magnetic field disappears once a\nvery small non-uniformity is introduced. Furthermore, we have shown\nanalytically and confirmed numerically that once the direction of one of the\nmagnetic field is along the Ising axis then no entangled states can be\nproduced, independently of the degree of non-uniformity of the magnetic fields\non each site.",
    "arxiv_id": "quant-ph/0407230",
    "authors": [
      "Andreas F. Terzis",
      "Emmanuel Paspalakis"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1016/j.physleta.2004.10.063",
    "title": "Entanglement in a Two-Qubit Ising Model Under a Site-Dependent External   Magnetic Field",
    "url": "https://arxiv.org/abs/quant-ph/0407230"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "8cbb703d-7bbc-4d72-9a0d-a986fc0b6c47",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}