{
  "id": "0804.4618",
  "version": "v1",
  "published": "2008-04-29T14:17:08.000Z",
  "updated": "2008-04-29T14:17:08.000Z",
  "title": "Fleming's bound for the decay of mixed states",
  "authors": [
    "Florian Fröwis",
    "Gebhard Grübl",
    "Markus Penz"
  ],
  "comment": "12 pages",
  "journal": "Journ Physics A 41 (2008) 405201 (11pp)",
  "doi": "10.1088/1751-8113/41/40/405201",
  "categories": [
    "quant-ph"
  ],
  "abstract": "Fleming's inequality is generalized to the decay function of mixed states. We show that for any symmetric hamiltonian $h$ and for any density operator $\\rho$ on a finite dimensional Hilbert space with the orthogonal projection $\\Pi$ onto the range of $\\rho$ there holds the estimate $\\Tr(\\Pi \\rme^{-\\rmi ht}\\rho \\rme^{\\rmi ht}) \\geq\\cos^{2}((\\Delta h)_{\\rho}t) $ for all real $t$ with $(\\Delta h)_{\\rho}| t| \\leq\\pi/2.$ We show that equality either holds for all $t\\in\\mathbb{R}$ or it does not hold for a single $t$ with $0<(\\Delta h)_{\\rho}| t| \\leq\\pi/2.$ All the density operators saturating the bound for all $t\\in\\mathbb{R},$ i.e. the mixed intelligent states, are determined.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2008-04-29T14:17:08.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "mixed states",
      "flemings bound",
      "finite dimensional hilbert space",
      "density operator",
      "decay function"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "journal": "Journal of Physics A Mathematical General",
      "year": 2008,
      "month": "Oct",
      "volume": 41,
      "number": 40,
      "pages": 405201
    },
    "note": {
      "typesetting": "TeX",
      "pages": 12,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2008JPhA...41N5201F"
    }
  }
}