{
  "id": "0801.1318",
  "version": "v1",
  "published": "2008-01-08T23:00:52.000Z",
  "updated": "2008-01-08T23:00:52.000Z",
  "title": "Experimental studies of the fractional quantum Hall effect in the first excited Landau level",
  "authors": [
    "W. Pan",
    "J. S. Xia",
    "H. L. Stormer",
    "D. C. Tsui",
    "C. Vicente",
    "E. D. Adams",
    "N. S. Sullivan",
    "L. N. Pfeiffer",
    "K. W. Baldwin",
    "K. W. West"
  ],
  "comment": "to be published",
  "doi": "10.1103/PhysRevB.77.075307",
  "categories": [
    "cond-mat.mes-hall"
  ],
  "abstract": "We present a spectrum of experimental data on the fractional quantum Hall effect (FQHE) states in the first excited Landau level, obtained in an ultrahigh mobility two-dimensional electron system (2DES) and at very low temperatures and report the following results: For the even-denominator FQHE states, the sample dependence of the nu=5/2 state clearly shows that disorder plays an important role in determining the energy gap at nu=5/2. For the developing nu=19/8 FQHE state the temperature dependence of the Rxx minimum implies an energy gap of ~5mK.The energy gaps of the odd-denominator FQHE states at nu=7/3 and 8/3 also increase with decreasing disorder, similar to the gap at 5/2 state. Unexpectedly and contrary to earlier data on lower mobility samples, in this ultra-high quality specimen, the nu=13/5 state is missing, while its particle-hole conjugate state, the nu=12/5 state, is a fully developed FQHE state. We speculate that this disappearance might indicate a spin polarization of the nu=13/5 state. Finally, the temperature dependence is studied for the two-reentrant integer quantum Hall states around nu=5/2 and is found to show a very narrow temperature range for the transition from quantized to classical value.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2008-01-08T23:00:52.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "73.43.Qt",
      "73.20.Qt",
      "73.63.Hs"
    ],
    "keywords": [
      "fractional quantum hall effect",
      "first excited landau level",
      "integer quantum hall states",
      "experimental studies",
      "fqhe state"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Physical Review B",
      "year": 2008,
      "month": "Feb",
      "volume": 77,
      "number": 7,
      "pages": "075307"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2008PhRvB..77g5307P"
    }
  }
}