{
  "id": "1405.3165",
  "version": "v2",
  "published": "2014-05-13T14:31:40.000Z",
  "updated": "2015-03-05T16:58:49.000Z",
  "title": "A theoretical study of the dynamics of atomic hydrogen on graphene bilayers",
  "authors": [
    "M. Moaied",
    "J. A. Moreno",
    "M. J. Caturla",
    "F. Ynduráin",
    "J. J. Palacios"
  ],
  "comment": "A mistake in the evaluation of the migration barrier has been corrected and the discussion has been changed accordingly. This version is significantly different from the original one",
  "categories": [
    "cond-mat.mes-hall",
    "cond-mat.mtrl-sci"
  ],
  "abstract": "We present a theoretical study of the dynamics of H atoms adsorbed on graphene bilayers with Bernal stacking. First, through extensive density functional theory calculations, including van der Waals interactions, we obtain the activation barriers involved in the desorption and migration processes of a single H atom. These barriers, along with attempt rates and the energetics of H pairs, are used as input parameters in kinetic Monte Carlo simulations to study the time evolution of an initial random distribution of adsorbed H atoms. The simulations reveal that, at room temperature, H atoms occupy only one sublattice before they completely desorb or form clusters. This sublattice selectivity in the distribution of H atoms may last for sufficiently long periods of time upon lowering the temperature down to 0 C. The final fate of the H atoms, namely, desorption or cluster formation, depends on the actual relative values of the activation barriers which can be tuned by doping. In some cases a sublattice selectivity can be obtained for periods of time experimentally relevant even at room temperature. This result shows the possibility for observation and applications of the ferromagnetic state associated with such distribution.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2014-05-13T14:31:40.000Z",
      "title": "A theoretical study of the dynamics of atomic hydrogen adsorbed on graphene multilayers",
      "abstract": "We present a theoretical study of the dynamics of H atoms adsorbed on bilayer graphene and graphite. First, through density functional theory calculations, we obtain the relevant activation barriers, namely, desorption and migration, for a single H atom on bilayer graphene. These barriers, along with the energetics of H pairs, are used as input parameters in kinetic Monte Carlo simulations to study the time evolution of an initial random distribution of adsorbed atoms. The simulations reveal that the atoms tend to desorb or form dimers and clusters after a few minutes at room temperature. Interestingly, either a minor increase in the activation barriers, as may be the case for graphite surfaces, or lower temperatures (approx. 0 C) completely changes this picture. Then it is possible to obtain a redistribution of nearly all H atoms among the sites of only one sublattice for a period of time of hours or even days. This opens the possibility for observation and applications of the predicted ferromagnetic state associated with such sublattice polarized distribution of H.",
      "comment": "8 pages, 9 figures",
      "journal": null,
      "doi": null,
      "authors": [
        "M. Moaied",
        "J. A. Moreno",
        "M. J. Caturla",
        "J. J. Palacios"
      ]
    },
    {
      "version": "v2",
      "updated": "2015-03-05T16:58:49.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "73.20.Hb",
      "73.22.Pr",
      "68.35.Fx"
    ],
    "keywords": [
      "graphene bilayers",
      "theoretical study",
      "atomic hydrogen",
      "extensive density functional theory calculations",
      "kinetic monte carlo simulations"
    ],
    "publication": {
      "doi": "10.1103/PhysRevB.91.155419",
      "journal": "Physical Review B",
      "year": 2015,
      "month": "Apr",
      "volume": 91,
      "number": 15,
      "pages": 155419
    },
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2015PhRvB..91o5419M"
    }
  }
}