Electron-hole asymmetric integer and fractional quantum Hall effect in bilayer graphene

@article{Kou2014ElectronholeAI,
  title={Electron-hole asymmetric integer and fractional quantum Hall effect in bilayer graphene},
  author={Angela Kou and Benjamin E. Feldman and Andrei J Levin and Bertrand I. Halperin and K. Watanabe and Takashi Taniguchi and Amir Yacoby},
  journal={Science},
  year={2014},
  volume={345},
  pages={55 - 57}
}
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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