{
  "id": "1910.01190",
  "version": "v1",
  "published": "2019-10-02T19:52:49.000Z",
  "updated": "2019-10-02T19:52:49.000Z",
  "title": "Fate of electron beam in graphene: Coulomb relaxation or plasma instability?",
  "authors": [
    "Dmitry Svintsov"
  ],
  "comment": "7 pages, 3 figures",
  "categories": [
    "cond-mat.mes-hall",
    "physics.plasm-ph"
  ],
  "abstract": "Electron beams in two-dimensional systems can provide a useful tool to study energy-momentum relaxation of electrons and to generate microwave radiation stemming from plasma-beam instabilities. Naturally, these two applications cannot coexist: if beam electrons do relax, the beam is stabilized; if instability exists, it strongly distorts the distribution function of beam electrons. In this paper, we study the competition of beam relaxation due to electron-electron (e-e) collisions and development of plasma beam instability in graphene. We find that unstable plasma mode associated with a beam is stabilized already by weak e-e collisions. At intermediate e-e collision frequency, the instability re-appears at the ordinary graphene plasmon mode. Such instability is interpreted as viscous transfer of momentum from beam to 2d plasmons. Its growth rate reaches its maximum at hydrodynamic-to-ballistic crossover, when plasmon wavelength and electron mean free path are of the same order of magnitude.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2019-10-02T19:52:49.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "electron beam",
      "coulomb relaxation",
      "plasma instability",
      "electron mean free path",
      "ordinary graphene plasmon mode"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 7,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}