{
  "annotation_id": "6947018f-781a-48ac-99cf-f956da0131f6",
  "date_created": "2026-03-02T18:02:07.055000Z",
  "date_modified": "2026-03-02T18:02:07.055000Z",
  "file_hash": "a42d8619f2c58244371ba8c4ea6d4d4983c899e7a3e7b4a9b9327d668e96312a",
  "private": false,
  "record": {
    "abstract": "We study entanglement in Valence-Bond-Solid state. It describes the ground\nstate of Affleck, Kennedy, Lieb and Tasaki quantum spin chain. The AKLT model\nhas a gap and open boundary conditions. We calculate an entropy of a subsystem\n(continuous block of spins). It quantifies the entanglement of this block with\nthe rest of the ground state. We prove that the entanglement approaches a\nconstant value exponentially fast as the size of the subsystem increases.\nActually we proved that the density matrix of the continuous block of spins\ndepends only on the length of the block, but not on the total size of the chain\n[distance to the ends also not essential]. We also study reduced density\nmatrices of two spins both in the bulk and on the boundary. We evaluated\nconcurrencies.",
    "arxiv_id": "quant-ph/0406067",
    "authors": [
      "Heng Fan",
      "Vladimir Korepin",
      "Vwani Roychowdhury"
    ],
    "categories": [
      "quant-ph",
      "cond-mat.stat-mech"
    ],
    "doi": "10.1103/PhysRevLett.93.227203",
    "journal_ref": "PRL, vol 93, issue 22, 227203, 2004",
    "title": "Entanglement in a Valence-Bond-Solid State",
    "url": "https://arxiv.org/abs/quant-ph/0406067"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "87736301-1347-4670-864f-aacf53edfdb0",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}