{
  "id": "1408.1590",
  "version": "v2",
  "published": "2014-08-07T13:50:58.000Z",
  "updated": "2014-09-19T20:09:28.000Z",
  "title": "Effects of disorder on electron tunneling through helical edge states",
  "authors": [
    "Pietro Sternativo",
    "Fabrizio Dolcini"
  ],
  "comment": "14 pages, 7 figures",
  "journal": "Phys. Rev. B 90, 125135 (2014)",
  "doi": "10.1103/PhysRevB.90.125135",
  "categories": [
    "cond-mat.mes-hall"
  ],
  "abstract": "A tunnel junction between helical edge states, realized via a constriction in a Quantum Spin Hall system, can be exploited to steer both charge and spin current into various terminals. We investigate the effects of disorder on the transmission coefficient $T_p$ of the junction, by modelling disorder with a randomly varying (complex) tunneling amplitude $\\Gamma_p=|\\Gamma_p| \\exp[i \\phi_p]$. We show that, while for a clean junction $T_p$ is only determined by the absolute value $|\\Gamma_p|$ and is independent of the phase $\\phi_p$, the situation can be quite different in the presence of disorder: phase fluctuations may dramatically affect the energy dependence of $T_p$ of any single sample. Furthermore, analysing three different models for phase disorder (including correlated ones), we show that not only the amount but also the way the phase $\\phi_p$ fluctuates determines the localisation length $\\xi_{loc}$ and the sample-averaged transmission. Finally, we discuss the physical conditions in which these three models suitably apply to realistic cases.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2014-08-07T13:50:58.000Z",
      "journal": null,
      "doi": null
    },
    {
      "version": "v2",
      "updated": "2014-09-19T20:09:28.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "73.23.-b",
      "73.43.Jn",
      "71.23.-k"
    ],
    "keywords": [
      "helical edge states",
      "electron tunneling",
      "quantum spin hall system",
      "tunnel junction",
      "spin current"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Physical Review B",
      "year": 2014,
      "month": "Sep",
      "volume": 90,
      "number": 12,
      "pages": 125135
    },
    "note": {
      "typesetting": "TeX",
      "pages": 14,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2014PhRvB..90l5135S"
    }
  }
}