{
  "id": "2203.14575",
  "version": "v1",
  "published": "2022-03-28T08:41:50.000Z",
  "updated": "2022-03-28T08:41:50.000Z",
  "title": "Impact of in-situ controlled disorder screening on fractional quantum Hall effects and composite-fermion transport",
  "authors": [
    "T. Akiho",
    "K. Muraki"
  ],
  "comment": "6 pages, 4 figures",
  "categories": [
    "cond-mat.mes-hall"
  ],
  "abstract": "We examine the impact of random potential due to remote impurites (RIs) and its in-situ controlled screening on fractional quantum Hall effects (FQHEs) around Landau-level filling factor $\\nu = 1/2$. The experiment is made possible by using a dual-gate GaAs quantum well (QW) that allows for the independent control of the density $n_{e}$ of the two-dimensional electron system in the QW and that ($n_\\text{SL}$) of excess electrons in the modulation-doping superlattice. As the screening is reduced by decreasing $n_\\text{SL}$ at a fixed $n_{e}$, we observe a decrease in the apparent energy gap of the FQHEs deduced from thermal activation, which signifies a corresponding increase in the disorder broadening $\\Gamma$ of composite fermions (CFs). Interestingly, the increase in $\\Gamma$ is accompanied by a noticeable increase in the longitudinal resistivity at $\\nu = 1/2$ ($\\rho_{1/2}$), with a much stronger correlation with $\\Gamma$ than electron mobility $\\mu$ has. The in-situ control of RI screening enables us to disentangle the contributions of RIs and background impurities (BIs) to $\\rho_{1/2}$, with the latter in good agreement with the CF theory. We construct a scaling plot that helps in estimating the BI contribution to $\\rho_{1/2}$ for a given set of $n_{e}$ and $\\mu$.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2022-03-28T08:41:50.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "fractional quantum hall effects",
      "in-situ controlled disorder screening",
      "composite-fermion transport",
      "apparent energy gap",
      "dual-gate gaas quantum"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 6,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}