{
  "id": "cond-mat/0106472",
  "version": "v1",
  "published": "2001-06-22T16:32:24.000Z",
  "updated": "2001-06-22T16:32:24.000Z",
  "title": "Exchange instability of the two-dimensional electron gas in semiconductor quantum wells",
  "authors": [
    "A. R. Goñi",
    "U. Haboeck",
    "C. Thomsen",
    "K. Eberl",
    "F. A. Reboredo",
    "C. R. Proetto",
    "F. Guinea"
  ],
  "doi": "10.1103/PhysRevB.65.121313",
  "categories": [
    "cond-mat.mes-hall"
  ],
  "abstract": "A two-dimensional (2D) electron gas formed in a modulation-doped GaAs/AlGaAs single quantum well undergoes a first-order transition when the first excited subband is occupied with electrons, as the Fermi level is tuned into resonance with the excited subband by applying a dc voltage. Direct evidence for this effect is obtained from low-temperature photoluminescence spectra which display the sudden renormalization of the intersubband energy $E_{01}$ upon the abrupt occupation of the first excited subband. Calculations within density-functional theory, which treat the 2D exchange potential {\\it exactly}, show that this thermodynamical instability of the electron system is mainly driven by {\\it intersubband} terms of the exchange Coulomb interaction. From temperature-dependent measurements the existence of a critical point at $T_c = 35\\pm 5$ K is inferred.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2001-06-22T16:32:24.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "two-dimensional electron gas",
      "semiconductor quantum wells",
      "exchange instability",
      "first excited subband",
      "low-temperature photoluminescence spectra"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Phys. Rev. B"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}