{
  "id": "1008.4136",
  "version": "v2",
  "published": "2010-08-24T20:00:11.000Z",
  "updated": "2011-08-19T13:08:39.000Z",
  "title": "Faithful nonclassicality indicators and extremal quantum correlations in two-qubit states",
  "authors": [
    "Davide Girolami",
    "Mauro Paternostro",
    "Gerardo Adesso"
  ],
  "comment": "7 pages, 2 figures, 1 table. Published version",
  "journal": "J. Phys. A: Math. Theor. 44, 352002 (2011)",
  "doi": "10.1088/1751-8113/44/35/352002",
  "categories": [
    "quant-ph",
    "cond-mat.other",
    "hep-th",
    "math-ph",
    "math.MP"
  ],
  "abstract": "The state disturbance induced by locally measuring a quantum system yields a signature of nonclassical correlations beyond entanglement. Here we present a detailed study of such correlations for two-qubit mixed states. To overcome the asymmetry of quantum discord and the unfaithfulness of measurement-induced disturbance (severely overestimating quantum correlations), we propose an ameliorated measurement-induced disturbance as nonclassicality indicator, optimized over joint local measurements, and we derive its closed expression for relevant two-qubit states. We study its analytical relation with discord, and characterize the maximally quantum-correlated mixed states, that simultaneously extremize both quantifiers at given von Neumann entropy: among all two-qubit states, these states possess the most robust quantum correlations against noise.",
  "revisions": [
    {
      "version": "v2",
      "updated": "2011-08-19T13:08:39.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "03.67.-a",
      "03.65.Ta"
    ],
    "keywords": [
      "extremal quantum correlations",
      "faithful nonclassicality indicators",
      "mixed states",
      "quantum system yields",
      "joint local measurements"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "journal": "Journal of Physics A Mathematical General",
      "year": 2011,
      "month": "Sep",
      "volume": 44,
      "number": 35,
      "pages": 352002
    },
    "note": {
      "typesetting": "TeX",
      "pages": 7,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 924446,
      "adsabs": "2011JPhA...44I2002G"
    }
  }
}