{
  "id": "quant-ph/0012015",
  "version": "v1",
  "published": "2000-12-04T16:33:14.000Z",
  "updated": "2000-12-04T16:33:14.000Z",
  "title": "Optimal estimation of quantum dynamics",
  "authors": [
    "A. Acin",
    "E. Jane",
    "G. Vidal"
  ],
  "comment": "4 pages, REVTEX",
  "journal": "Phys. Rev. A 64, 050302(R) (2001).",
  "doi": "10.1103/PhysRevA.64.050302",
  "categories": [
    "quant-ph"
  ],
  "abstract": "We construct the optimal strategy for the estimation of an unknown unitary transformation $U\\in SU(d)$. This includes, in addition to a convenient measurement on a probe system, finding which is the best initial state on which $U$ is to act. When $U\\in SU(2)$, such an optimal strategy can be applied to estimate simultaneously both the direction and the strength of a magnetic field, and shows how to use a spin 1/2 particle to transmit information about a whole coordinate system instead of only a direction in space.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2000-12-04T16:33:14.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "quantum dynamics",
      "optimal estimation",
      "optimal strategy",
      "coordinate system",
      "unknown unitary transformation"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Phys. Rev. A"
    },
    "note": {
      "typesetting": "RevTeX",
      "pages": 4,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}