{
  "id": "1106.5819",
  "version": "v1",
  "published": "2011-06-28T22:52:36.000Z",
  "updated": "2011-06-28T22:52:36.000Z",
  "title": "Perfect Andreev Reflection of Helical Edge Modes in InAs/GaSb Quantum Wells",
  "authors": [
    "Ivan Knez",
    "Rui-Rui Du",
    "Gerard Sullivan"
  ],
  "doi": "10.1103/PhysRevLett.109.186603",
  "categories": [
    "cond-mat.mes-hall",
    "cond-mat.supr-con"
  ],
  "abstract": "We present an experimental study of inverted InAs/GaSb composite quantum wells in the hybridization regime and contacted by superconducting electrodes. A front gate is used to vary the Fermi level into the mini-gap, where recent experiments indicate existence of helical edge modes [arXiv:1105.0137]. Zero bias dips in differential resistance are observed across the mini-gap, suggesting transport dominated by Andreev reflection processes. Evolution of the mini-gap differential resistance with applied bias as well as measured mini-gap excess current of 150 nA are in good agreement with the prediction of perfect Andreev reflection of the helical edge modes, which is necessitated by the absence of back-scattering channels. The perfect Andreev reflection occurs in spite of a finite barrier at the interface and shows strong sensitivity to time-reversal breaking - hallmarks of the helical nature of quantum spin Hall edges.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2011-06-28T22:52:36.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "72.25.Dc",
      "73.63.Hs",
      "74.45.+c"
    ],
    "keywords": [
      "perfect andreev reflection",
      "helical edge modes",
      "inas/gasb quantum wells",
      "inas/gasb composite quantum wells",
      "quantum spin hall edges"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Physical Review Letters",
      "year": 2012,
      "month": "Nov",
      "volume": 109,
      "number": 18,
      "pages": 186603
    },
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2012PhRvL.109r6603K"
    }
  }
}