{
  "annotation_id": "1912dbd1-a7f7-4162-8c53-eb444a693492",
  "date_created": "2026-03-02T18:02:31.142000Z",
  "date_modified": "2026-03-02T18:02:31.142000Z",
  "file_hash": "152b8e5d718abe55cb388c9c1179dd7ce59317271077db7430b69fb0f5c839be",
  "private": false,
  "record": {
    "abstract": "The notion of low-noise channels was recently proposed and analyzed in detail\nin order to describe noise-processes driven by environment [M. Hotta, T.\nKarasawa and M. Ozawa, Phys. Rev. A72, 052334 (2005)]. An estimation theory of\nlow-noise parameters of channels has also been developed. In this report, we\naddress the low-noise parameter estimation problem for the $N$-body extension\nof low-noise channels. We perturbatively calculate the Fisher information of\nthe output states in order to evaluate the lower-bound of the mean-square error\nof the parameter estimation. We show that the maximum of the Fisher information\nover all input states can be attained by a factorized input state in the\nleading order of the low-noise parameter. Thus, to achieve optimal estimation,\nit is not necessary for there to be entanglement of the $N$ subsystems, as long\nas the true low-noise parameter is sufficiently small.",
    "arxiv_id": "quant-ph/0609218",
    "authors": [
      "M. Hotta",
      "T. Karasawa",
      "M. Ozawa"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1088/0305-4470/39/46/015",
    "journal_ref": "J. Phys. A: Math. Gen. 39 No 46 (17 November 2006) 14465-14470",
    "title": "N-body-extended Channel Estimation for Low-Noise Parameters",
    "url": "https://arxiv.org/abs/quant-ph/0609218"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "e2014712-4a32-48a4-931f-9632a08b9710",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}