{
  "id": "2011.06721",
  "version": "v1",
  "published": "2020-11-13T01:57:29.000Z",
  "updated": "2020-11-13T01:57:29.000Z",
  "title": "Observation of spontaneous valley polarization of itinerant electrons",
  "authors": [
    "Md. S. Hossain",
    "M. K. Ma",
    "K. A. Villegas Rosales",
    "Y. J. Chung",
    "\\Ł. N. Pfeiffer",
    "K. W. West",
    "K. W. Baldwin",
    "M. Shayegan"
  ],
  "categories": [
    "cond-mat.mes-hall",
    "cond-mat.mtrl-sci",
    "cond-mat.str-el",
    "physics.app-ph"
  ],
  "abstract": "Memory or transistor devices based on electron's spin rather than its charge degree of freedom offer certain distinct advantages and comprise a cornerstone of spintronics \\cite{Zutic.RMP.2004}. Recent years have witnessed the emergence of a new field, valleytronics, which seeks to exploit electron's valley index rather than its spin. An important component in this quest would be the ability to control the valley index in a convenient fashion. Here we show that the valley polarization can be switched from zero to one by a small reduction in density, simply tuned by a gate bias, in a two-dimensional electron system. This phenomenon arises fundamentally as a result of electron-electron interaction in an itinerant, dilute electron system. Essentially, the kinetic energy favors an equal distribution of electrons over the available valleys, whereas the interaction between electrons prefers single-valley occupancy below a critical density. The gate-bias-tuned transition we observe is accompanied by a sudden, two-fold change in sample resistance, making the phenomenon of interest for potential valleytronic transistor device applications. Our observation constitutes a quintessential demonstration of valleytronics in a very simple experiment.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2020-11-13T01:57:29.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "spontaneous valley polarization",
      "itinerant electrons",
      "observation",
      "potential valleytronic transistor device applications",
      "electron system"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}