{
  "id": "1703.03496",
  "version": "v1",
  "published": "2017-03-10T00:56:25.000Z",
  "updated": "2017-03-10T00:56:25.000Z",
  "title": "A Momentum-Resolved View on Electron-Phonon Coupling in Multilayer WSe$_2$",
  "authors": [
    "Lutz Waldecker",
    "Roman Bertoni",
    "H. Hübener",
    "Thomas Brumme",
    "Thomas Vasileiadis",
    "Daniela Zahn",
    "Angel Rubio",
    "Ralph Ernstorfer"
  ],
  "categories": [
    "cond-mat.mes-hall"
  ],
  "abstract": "We investigate the interactions of photoexcited carriers with lattice vibrations in thin films of the layered transition metal dichalcogenide (TMDC) WSe$_2$. Employing femtosecond electron diffraction with monocrystalline samples and first principle density functional theory calculations, we obtain a momentum-resolved picture of the energy-transfer from excited electrons to phonons. The measured momentum-dependent phonon population dynamics are compared to first principle calculations of the phonon linewidth and can be rationalized in terms of electronic phase-space arguments. The relaxation of excited states in the conduction band is dominated by intervalley scattering between $\\Sigma$ valleys and the emission of zone-boundary phonons. Transiently, the momentum-dependent electron-phonon coupling leads to a non-thermal phonon distribution, which, on longer timescales, relaxes to a thermal distribution via electron-phonon and phonon-phonon collisions. Our results constitute a basis for monitoring and predicting out of equilibrium electrical and thermal transport properties for nanoscale applications of TMDCs.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2017-03-10T00:56:25.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "electron-phonon coupling",
      "multilayer wse",
      "momentum-resolved view",
      "first principle density functional theory",
      "principle density functional theory calculations"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}