Correlated insulator behaviour at half-filling in magic-angle graphene superlattices

Published 5 April 2018 · Nature · Journal article

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Summary

This companion paper reports that twisted bilayer graphene at the magic angle exhibits insulating states at half-filling of the flat moire bands, where simple band theory would predict a metal. The authors interpret these as Mott-like correlated insulators arising from strong electron-electron interactions in the nearly flat bands. The result demonstrates that twist-angle engineering can drive graphene into strongly correlated electronic phases.

Key findings

Insulating states appear at half-filling of the flat bands in magic-angle twisted bilayer graphene.
These states are attributed to Coulomb-driven Mott-like correlated insulator behaviour rather than band effects.
Companion to the superconductivity paper, together mapping a correlated phase diagram in moire graphene.

Subjects & keywords

Physics twisted bilayer graphene correlated insulator magic angle mott insulator flat bands

Cite this paper

APA

Yuan Cao, Valla Fatemi, Ahmet Demir, Shiang Fang, Spencer L. Tomarken, Jason Y. Luo, Javier D. Sanchez-Yamagishi, Kenji Watanabe, Takashi Taniguchi, Efthimios Kaxiras, Ray C. Ashoori, & Pablo Jarillo-Herrero [Twelve authors; full list given in publication order.] (2018). Correlated insulator behaviour at half-filling in magic-angle graphene superlattices. Nature. https://doi.org/10.1038/nature26154

BibTeX

@article{cao2018correlated,
  author    = {Yuan Cao and Valla Fatemi and Ahmet Demir and Shiang Fang and Spencer L. Tomarken and Jason Y. Luo and Javier D. Sanchez-Yamagishi and Kenji Watanabe and Takashi Taniguchi and Efthimios Kaxiras and Ray C. Ashoori and Pablo Jarillo-Herrero and {Twelve authors; full list given in publication order.}},
  title     = {Correlated insulator behaviour at half-filling in magic-angle graphene superlattices},
  journal   = {Nature},
  year      = {2018},
  doi       = {10.1038/nature26154},
  url       = {https://doi.org/10.1038/nature26154}
}

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