Cascade of phase transitions and Dirac revivals in magic-angle graphene

@article{Zondiner2020CascadeOP,
  title={Cascade of phase transitions and Dirac revivals in magic-angle graphene},
  author={Uri Zondiner and Asaf Rozen and Daniel Rodan-Legrain and Y. Cao and Raquel Queiroz and Takashi Taniguchi and K. Watanabe and Yuval Oreg and Felix von Oppen and Ady Stern and Erez Berg and Pablo Jarillo-Herrero and Shahal Ilani},
  journal={Nature},
  year={2020},
  volume={582},
  pages={203-208}
}
Twisted bilayer graphene near the magic angle 1 – 4 exhibits rich electron-correlation physics, displaying insulating 3 – 6 , magnetic 7 , 8 and superconducting phases 4 – 6 . The electronic bands of this system were predicted 1 , 2 to narrow markedly 9 , 10 near the magic angle, leading to a variety of possible symmetry-breaking ground states 11 – 17 . Here, using measurements of the local electronic compressibility, we show that these correlated phases originate from a high-energy state with… 
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