{
  "id": "1408.5263",
  "version": "v1",
  "published": "2014-08-22T10:58:10.000Z",
  "updated": "2014-08-22T10:58:10.000Z",
  "title": "Stacking faults as quantum wells in nanowires: Density of states, oscillator strength and radiative efficiency",
  "authors": [
    "P. Corfdir",
    "C. Hauswald",
    "J. K. Zettler",
    "T. Flissikowski",
    "J. Lähnemann",
    "S. Fernández-Garrido",
    "L. Geelhaar",
    "H. T. Grahn",
    "O. Brandt"
  ],
  "categories": [
    "cond-mat.mes-hall"
  ],
  "abstract": "We investigate the nature of excitons bound to I1 basal-plane stacking faults [(I1;X)] in GaN nanowire ensembles by continuous-wave and time-resolved photoluminescence spectroscopy. Based on the linear increase of the radiative lifetime of these excitons with temperature, they are demonstrated to exhibit a two-dimensional density of states, i. e., a basal-plane stacking fault acts as a quantum well. From the slope of the linear increase, we determine the oscillator strength of the (I1;X) and show that the value obtained reflects the presence of large internal electrostatic fields across the stacking fault. While the recombination of donor-bound and free excitons in the GaN nanowire ensemble is dominated by nonradiative phenonema already at 10 K, we observe that the (I1;X) recombines purely radiatively up to 60 K. This finding provides important insight into the nonradiative recombination processes in GaN nanowires. First, the radiative lifetime of about 6 ns measured at 60 K sets an upper limit for the surface recombination velocity of 450 cm/s considering the nanowires mean diameter of 105 nm. Second, the density of nonradiative centers responsible for the fast decay of donor-bound and free excitons cannot be higher than 2x10^16 cm^-3. As a consequence, the nonradiative decay of donor-bound excitons in these GaN nanowire ensembles has to occur indirectly via the free exciton state.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2014-08-22T10:58:10.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "78.67.Uh",
      "71.35.-y",
      "71.55.Eq",
      "78.47.jd"
    ],
    "keywords": [
      "oscillator strength",
      "quantum wells",
      "radiative efficiency",
      "gan nanowire ensemble",
      "free exciton"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1103/PhysRevB.90.195309",
      "journal": "Physical Review B",
      "year": 2014,
      "month": "Nov",
      "volume": 90,
      "number": 19,
      "pages": 195309
    },
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2014PhRvB..90s5309C"
    }
  }
}