{
  "annotation_id": "b919d5ea-45d6-4d8b-ac9b-defbf11775c0",
  "date_created": "2026-03-02T18:02:34.656000Z",
  "date_modified": "2026-03-02T18:02:34.656000Z",
  "file_hash": "408094ab99add1c45605a3b2f5e286d691e0d75b6fbf0b6e47c9e17f4133eba3",
  "private": false,
  "record": {
    "abstract": "Recently, Yu, Brown, and Chuang [Phys. Rev. A {\\bf 71}, 032341 (2005)]\ninvestigated the entanglement attainable from unitary transformed thermal\nstates in liquid-state nuclear magnetic resonance (NMR). Their research gave an\ninsight into the role of the entanglement in a liquid-state NMR quantum\ncomputer. Moreover, they attempted to reveal the role of mixed-state\nentanglement in quantum computing. However, they assumed that the Zeeman energy\nof each nuclear spin which corresponds to a qubit takes a common value for all;\nthere is no chemical shift. In this paper, we research a model with the\nchemical shifts and analytically derive the physical parameter region where\nunitary transformed thermal states are entangled, by the positive partial\ntransposition (PPT) criterion with respect to any bipartition. We examine the\neffect of the chemical shifts on the boundary between the separability and the\nnonseparability, and find it is negligible.",
    "arxiv_id": "quant-ph/0612158",
    "authors": [
      "Yukihiro Ota",
      "Shuji Mikami",
      "Motoyuki Yoshida",
      "Ichiro Ohba"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1088/1751-8113/40/47/016",
    "journal_ref": "J. Phys. A: Math. Theor. 40, (2007) 14263-14277.",
    "title": "Attainable entanglement of unitary transformed thermal states in   liquid-state nuclear magnetic resonance with the chemical shift",
    "url": "https://arxiv.org/abs/quant-ph/0612158"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "778fe371-a826-45be-81bf-a059e3887c45",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}