{
  "id": "0808.1257",
  "version": "v2",
  "published": "2008-08-08T18:41:23.000Z",
  "updated": "2008-11-19T19:27:18.000Z",
  "title": "Charge Imbalance and Bilayer 2D Electron Systems at $ν_T = 1$",
  "authors": [
    "A. R. Champagne",
    "A. D. K. Finck",
    "J. P. Eisenstein",
    "L. N. Pfeiffer",
    "K. W. West"
  ],
  "comment": "13 pages, 8 postscript figures. Final published version",
  "journal": "Phys. Rev. B 78, 205310 (2008)",
  "doi": "10.1103/PhysRevB.78.205310",
  "categories": [
    "cond-mat.mes-hall"
  ],
  "abstract": "We use interlayer tunneling to study bilayer 2D electron systems at $\\nu_T = 1$ over a wide range of charge density imbalance, $\\Delta \\nu =\\nu_1-\\nu_2$, between the two layers. We find that the strongly enhanced tunneling associated with the coherent excitonic $\\nu_T = 1$ phase at small layer separation can survive at least up to an imbalance of $\\Delta \\nu$ = 0.5, i.e $(\\nu_1, \\nu_2)$ = (3/4, 1/4). Phase transitions between the excitonic $\\nu_T = 1$ state and bilayer states which lack significant interlayer correlations can be induced in three different ways: by increasing the effective interlayer spacing $d/\\ell$, the temperature $T$, or the charge imbalance, $\\Delta \\nu$. We observe that close to the phase boundary the coherent $\\nu_T = 1$ phase can be absent at $\\Delta \\nu$ = 0, present at intermediate $\\Delta \\nu$, but then absent again at large $\\Delta \\nu$, thus indicating an intricate phase competition between it and incoherent quasi-independent layer states. At zero imbalance, the critical $d/\\ell$ shifts linearly with temperature, while at $\\Delta \\nu$ = 1/3 the critical $d/\\ell$ is only weakly dependent on $T$. At $\\Delta \\nu$ = 1/3 we report the first observation of a direct phase transition between the coherent excitonic $\\nu_T = 1$ bilayer integer quantum Hall phase and the pair of single layer fractional quantized Hall states at $\\nu_1$ = 2/3 and $\\nu_2=1/3$.",
  "revisions": [
    {
      "version": "v2",
      "updated": "2008-11-19T19:27:18.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "73.43.Jn",
      "71.10.Pm",
      "71.35.Lk",
      "73.43.Nq"
    ],
    "keywords": [
      "charge imbalance",
      "fractional quantized hall states",
      "layer fractional quantized hall",
      "study bilayer 2d electron systems",
      "bilayer integer quantum hall phase"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Physical Review B",
      "year": 2008,
      "month": "Nov",
      "volume": 78,
      "number": 20,
      "pages": 205310
    },
    "note": {
      "typesetting": "TeX",
      "pages": 13,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2008PhRvB..78t5310C"
    }
  }
}