{
  "annotation_id": "173c1769-13af-410c-93b9-576f417ca472",
  "date_created": "2026-03-02T18:02:06.509000Z",
  "date_modified": "2026-03-02T18:02:06.509000Z",
  "file_hash": "cb28dddef35bef7f80f0d6973f38954781ee20b1d8a17bcd75be7759fe21850b",
  "private": false,
  "record": {
    "abstract": "We associate to every quantum channel $T$ acting on a Hilbert space\n$\\mathcal{H}$ a pair of Hamiltonian operators over the symmetric subspace of\n$\\mathcal{H}^{\\otimes 2}$. The expectation values of these Hamiltonians over\nsymmetric product states give either the purity or the pure state fidelity of\n$T$. This allows us to analytically compute these measures for a wide class of\nchannels, and to identify states that are optimal with respect to these\nmeasures.",
    "arxiv_id": "quant-ph/0403074",
    "authors": [
      "Paolo Zanardi",
      "Daniel Lidar"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.70.012315",
    "journal_ref": "Phys. Rev. A 70, 012315 (2004)",
    "title": "Purity and State Fidelity of Quantum Channels via Hamiltonians",
    "url": "https://arxiv.org/abs/quant-ph/0403074"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "d5552490-c78c-4ec6-bba4-34a6ca226152",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}