{
  "id": "1803.11190",
  "version": "v2",
  "published": "2018-03-29T17:59:29.000Z",
  "updated": "2018-05-23T17:29:03.000Z",
  "title": "Unconventional superconductivity in nearly flat bands in twisted bilayer graphene",
  "authors": [
    "Bitan Roy",
    "Vladimir Juricic"
  ],
  "comment": "5 pages, 2 figure: Conclusions unchanged, Version submitted to Journal on 1st of May (New RG calculation + Supplementary Materials)",
  "categories": [
    "cond-mat.mes-hall",
    "cond-mat.str-el",
    "cond-mat.supr-con"
  ],
  "abstract": "Flat electronic bands can accommodate a plethora of interaction driven quantum phases, since kinetic energy is quenched therein and electronic interactions therefore prevail. Twisted bilayer graphene, near so-called the `magic angles', features \\emph{slow} Dirac fermions close to the charge-neutrality point (CNP) and \\emph{nearly} flat minibands around $1/4$ and $3/4$ fillings, which have also been observed in recent experiments. Starting from a continuum model of \\emph{slow} Dirac fermions, we show that with increasing chemical doping away from the CNP, a \\emph{time-reversal symmetry breaking, valley pseudo-spin-triplet, topological $p+ip$ superconductor} gradually sets in, when the system resides at the brink of an anti-ferromagnetic ordering (due to strong Hubbard repulsion), in qualitative agreement with experimental findings. The $p+ip$ paired state exhibits quantized spin and thermal Hall conductivities, polar Kerr and Faraday rotations. Our conclusion may also be operative within the minibands around $1/4$ or $3/4$ filling if they can be described in terms of slow Dirac fermions.",
  "revisions": [
    {
      "version": "v2",
      "updated": "2018-05-23T17:29:03.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "twisted bilayer graphene",
      "flat bands",
      "unconventional superconductivity",
      "interaction driven quantum phases",
      "strong hubbard repulsion"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 5,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}