{
  "id": "0802.0982",
  "version": "v2",
  "published": "2008-02-07T14:07:21.000Z",
  "updated": "2008-10-31T10:49:18.000Z",
  "title": "Spin-polarized current and shot noise in the presence of spin flip in a quantum dot via nonequilibrium Green's functions",
  "authors": [
    "F. M. Souza",
    "A. P. Jauho",
    "J. C. Egues"
  ],
  "comment": "Published version. 13 pages, 7 figures",
  "journal": "Phys. Rev. B 78, 155303 (2008)",
  "doi": "10.1103/PhysRevB.78.155303",
  "categories": [
    "cond-mat.mes-hall"
  ],
  "abstract": "Using non-equilibrium Green functions we calculate the spin-polarized current and shot noise in a ferromagnet--quantum-dot--ferromagnet (FM-QD-FM) system. Both parallel (P) and antiparallel (AP) magnetic configurations are considered. Coulomb interaction and coherent spin-flip (similar to a transverse magnetic field) are taken into account within the dot. We find that the interplay between Coulomb interaction and spin accumulation in the dot can result in a bias-dependent current polarization $\\wp$. In particular, $\\wp$ can be suppressed in the P alignment and enhanced in the AP case depending on the bias voltage. The coherent spin-flip can also result in a switch of the current polarization from the emitter to the collector lead. Interestingly, for a particular set of parameters it is possible to have a polarized current in the collector and an unpolarized current in the emitter lead. We also found a suppression of the Fano factor to values well below 0.5.",
  "revisions": [
    {
      "version": "v2",
      "updated": "2008-10-31T10:49:18.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "72.25.-b",
      "72.10.Bg",
      "85.75.-d",
      "73.63.Kv"
    ],
    "keywords": [
      "nonequilibrium greens functions",
      "shot noise",
      "spin-polarized current",
      "spin flip",
      "quantum dot"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Physical Review B",
      "year": 2008,
      "month": "Oct",
      "volume": 78,
      "number": 15,
      "pages": 155303
    },
    "note": {
      "typesetting": "TeX",
      "pages": 13,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2008PhRvB..78o5303S"
    }
  }
}