{
  "id": "1912.04397",
  "version": "v1",
  "published": "2019-12-09T22:04:58.000Z",
  "updated": "2019-12-09T22:04:58.000Z",
  "title": "Excess noise in Al${}_\\text{x}$Ga${}_\\text{1-x}$As/GaAs based quantum rings",
  "authors": [
    "Christian Riha",
    "Sven S. Buchholz",
    "Olivio Chiatti",
    "Andreas D. Wieck",
    "Dirk Reuter",
    "Saskia F. Fischer"
  ],
  "comment": "4 pages, 4 figures",
  "categories": [
    "cond-mat.mes-hall"
  ],
  "abstract": "Cross-correlated noise measurements are performed in etched Al${}_\\text{x}$Ga${}_\\text{1-x}$As/GaAs based quantum rings in equilibrium at bath temperature of $T_\\text{bath}=4.2\\text{ K}$. The measured white noise exceeds the thermal (Johnson-Nyquist) noise expected from the measured electron temperature $T_\\text{e}$ and the electrical resistance $R$. This excess part of the white noise decreases as $T_\\text{bath}$ increases and vanishes for $T_\\text{bath}\\geq 12\\text{ K}$. Excess noise is neither observed if one arm of a quantum ring is depleted of electrons nor in 1D-constrictions that have a length and width comparable to the quantum rings. A model is presented that suggests that the excess noise originates from the correlation of noise sources, mediated by phase-coherent propagation of electrons.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2019-12-09T22:04:58.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "quantum ring",
      "white noise decreases",
      "excess noise originates",
      "measured white noise exceeds",
      "excess part"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 4,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}