Tunable fractional quantum Hall phases in bilayer graphene

@article{Maher2014TunableFQ,
  title={Tunable fractional quantum Hall phases in bilayer graphene},
  author={Patrick Maher and Lei Wang and Yuanda Gao and Carlos Forsythe and Takashi Taniguchi and Kenji Watanabe and Dmitry A. Abanin and Zlatko Papi{\'c} and Paul Cadden-Zimansky and James C. Hone and Philip Kim and Cory R. Dean},
  journal={Science},
  year={2014},
  volume={345},
  pages={61 - 64}
}
Breaking down graphene degeneracy Bilayer graphene has two layers of hexagonally arranged carbon atoms stacked on top of each other in a staggered configuration. This spatial arrangement results in degenerate electronic states: distinct states that have the same energy. Interaction between electrons can cause the states to separate in energy, and so can external fields (see the Perspective by LeRoy and Yankowitz). Kou et al., Lee et al., and Maher et al. used three distinct experimental setups… 

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