{
  "id": "1108.1848",
  "version": "v1",
  "published": "2011-08-09T02:24:00.000Z",
  "updated": "2011-08-09T02:24:00.000Z",
  "title": "Selective probing of photo-induced charge and spin dynamics in the bulk and surface of a topological insulator",
  "authors": [
    "D. Hsieh",
    "F. Mahmood",
    "J. W. McIver",
    "D. R. Gardner",
    "Y. S. Lee",
    "N. Gedik"
  ],
  "comment": "Accepted to Phys. Rev. Lett",
  "journal": "Phys. Rev. Lett. 107, 077401 (2011)",
  "doi": "10.1103/PhysRevLett.107.077401",
  "categories": [
    "cond-mat.mes-hall"
  ],
  "abstract": "Topological insulators possess completely different spin-orbit coupled bulk and surface electronic spectra that are each predicted to exhibit exotic responses to light. Here we report time-resolved fundamental and second harmonic optical pump-probe measurements on the topological insulator Bi2Se3 to independently measure its photo-induced charge and spin dynamics with bulk and surface selectivity. Our results show that a transient net spin density can be optically induced in both the bulk and surface, which may drive spin transport in topological insulators. By utilizing a novel rotational anisotropy analysis we are able to separately resolve the spin de-polarization, intraband cooling and interband recombination processes following photo-excitation, which reveal that spin and charge degrees of freedom relax on very different time scales owing to strong spin-orbit coupling.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2011-08-09T02:24:00.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "78.68.+m",
      "03.65.Vf",
      "72.25.Dc",
      "78.47.J-"
    ],
    "keywords": [
      "topological insulator",
      "spin dynamics",
      "photo-induced charge",
      "selective probing",
      "second harmonic optical pump-probe measurements"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Physical Review Letters",
      "year": 2011,
      "month": "Aug",
      "volume": 107,
      "number": 7,
      "pages": "077401"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2011PhRvL.107g7401H"
    }
  }
}