English

Twisted Bilayer Graphene: A Phonon Driven Superconductor

Mesoscale and Nanoscale Physics 2019-07-03 v3 Superconductivity

Abstract

We study the electron-phonon coupling in twisted bilayer graphene (TBG), which was recently experimentally observed to exhibit superconductivity around the magic twist angle θ1.05\theta\approx 1.05^\circ. We show that phonon-mediated electron electron attraction at the magic angle is strong enough to induce a conventional intervalley pairing between graphene valleys KK and KK' with a superconducting critical temperature Tc1KT_c\sim1K, in agreement with the experiment. We predict that superconductivity can also be observed in TBG at many other angles θ\theta and higher electron densities in higher Moir\'e bands, which may also explain the possible granular superconductivity of highly oriented pyrolytic graphite. We support our conclusions by \emph{ab initio} calculations.

Keywords

Cite

@article{arxiv.1807.04382,
  title  = {Twisted Bilayer Graphene: A Phonon Driven Superconductor},
  author = {Biao Lian and Zhijun Wang and B. Andrei Bernevig},
  journal= {arXiv preprint arXiv:1807.04382},
  year   = {2019}
}

Comments

6+20 pages, 4+6 figures

R2 v1 2026-06-23T02:58:24.824Z