{
  "annotation_id": "1169db43-1c12-45b9-ad06-b8c732f921f5",
  "date_created": "2026-03-02T18:02:30.927000Z",
  "date_modified": "2026-03-02T18:02:30.927000Z",
  "file_hash": "a1fb513e2ba937a54fc38747489f3221c4823f5c4cd4a8fdc407ea9ca1442d91",
  "private": false,
  "record": {
    "abstract": "We define and study the properties of channels which are analogous to unital\nqubit channels in several ways. A full treatment can be given only when the\ndimension d is a prime power, in which case each of the (d+1) mutually unbiased\nbases (MUB) defines an axis. Along each axis the channel looks like a\ndepolarizing channel, but the degree of depolarization depends on the axis.\nWhen d is not a prime power, some of our results still hold, particularly in\nthe case of channels with one symmetry axis. We describe the convex structure\nof this class of channels and the subclass of entanglement breaking channels.\nWe find new bound entangled states for d = 3.\n  For these channels, we show that the multiplicativity conjecture for maximal\noutput p-norm holds for p=2. We also find channels with behavior not exhibited\nby unital qubit channels, including two pairs of orthogonal bases with equal\noutput entropy in the absence of symmetry. This provides new numerical evidence\nfor the additivity of minimal output entropy.",
    "arxiv_id": "quant-ph/0611106",
    "authors": [
      "M. Nathanson",
      "M. B. Ruskai"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1088/1751-8113/40/28/S22",
    "journal_ref": "J. Phys. A: Math. Theor. 40 (2007) 8171-8204.",
    "title": "Pauli Diagonal Channels Constant on Axes",
    "url": "https://arxiv.org/abs/quant-ph/0611106"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "ab2a1d07-7228-4e37-9ede-b53760d9ed70",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}