{
  "id": "2007.08036",
  "version": "v1",
  "published": "2020-07-15T23:52:51.000Z",
  "updated": "2020-07-15T23:52:51.000Z",
  "title": "Many-body effects in suspended graphene probed through magneto-phonon resonances",
  "authors": [
    "Stéphane Berciaud",
    "Marek Potemski",
    "Clément Faugeras"
  ],
  "comment": "8 pages, 5 figures",
  "categories": [
    "cond-mat.mes-hall"
  ],
  "abstract": "We make use of micro-magneto Raman scattering spectroscopy to probe magneto-phonon resonances (MPR) in suspended mono- to penta-layer graphene. MPR correspond to avoided crossings between zone-center optical phonons (G-mode) and optically-active inter Landau level (LL) transitions and provide a tool to perform LL spectroscopy at a fixed energy ($\\approx 197~\\rm{meV}$) set by the G-mode phonon. Using a single-particle effective bilayer model, we readily extract the velocity parameter associated with each MPR. A single velocity parameter slightly above the bulk graphite value suffices to fit all MPR for $N\\geq2$ layer systems. In contrast, in monolayer graphene, we find that the velocity parameter increases significantly from $\\approx (1.23\\pm0.01)~\\mathrm{m.s^{-1}}$ up to $\\approx (1.45\\pm0.02)~\\mathrm{m.s^{-1}}$ as the first to third optically-active inter LL transition couple to the G-mode phonon. This result is understood as a signature of enhanced many-body effects in unscreened graphene.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2020-07-15T23:52:51.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "many-body effects",
      "magneto-phonon resonances",
      "suspended graphene",
      "velocity parameter",
      "optically-active inter ll transition couple"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 8,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}