{
  "id": "1901.03520",
  "version": "v1",
  "published": "2019-01-11T09:19:33.000Z",
  "updated": "2019-01-11T09:19:33.000Z",
  "title": "Emergent ferromagnetism near three-quarters filling in twisted bilayer graphene",
  "authors": [
    "Aaron L. Sharpe",
    "Eli J. Fox",
    "Arthur W. Barnard",
    "Joe Finney",
    "Kenji Watanabe",
    "Takashi Taniguchi",
    "M. A. Kastner",
    "David Goldhaber-Gordon"
  ],
  "comment": "18 pages, 4 figures",
  "categories": [
    "cond-mat.mes-hall",
    "cond-mat.str-el"
  ],
  "abstract": "When two sheets of graphene are stacked at a small twist angle, the resulting flat superlattice minibands are expected to strongly enhance electron-electron interactions. Here we present evidence that near three-quarters ($3/4$) filling of the conduction miniband these enhanced interactions drive the twisted bilayer graphene into a ferromagnetic state. We observe emergent ferromagnetic hysteresis, with a giant anomalous Hall (AH) effect as large as $10.4\\ \\mathrm{k\\Omega}$ and signs of chiral edge states in a narrow density range around an apparent insulating state at $3/4$. Surprisingly, the magnetization of the sample can be reversed by applying a small DC current. Although the AH resistance is not quantized and dissipation is significant, we suggest that the system is an incipient Chern insulator.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2019-01-11T09:19:33.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "twisted bilayer graphene",
      "emergent ferromagnetism",
      "three-quarters filling",
      "small dc current",
      "narrow density range"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 18,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}