Edge channels of broken-symmetry quantum Hall states in graphene visualized by atomic force microscopy

@article{Kim2021EdgeCO,
  title={Edge channels of broken-symmetry quantum Hall states in graphene visualized by atomic force microscopy},
  author={Sungmin Kim and Johannes Schwenk and Daniel Walkup and Yihang Zeng and Fereshte Ghahari and Son T. Le and Marlou R. Slot and Julian Berwanger and Steve Blankenship and Kenji Watanabe and Takashi Taniguchi and Franz J. Giessibl and Nikolai B. Zhitenev and Cory R. Dean and Joseph A. Stroscio},
  journal={Nature Communications},
  year={2021},
  volume={12}
}
The quantum Hall (QH) effect, a topologically non-trivial quantum phase, expanded the concept of topological order in physics bringing into focus the intimate relation between the “bulk” topology and the edge states. The QH effect in graphene is distinguished by its four-fold degenerate zero energy Landau level (zLL), where the symmetry is broken by electron interactions on top of lattice-scale potentials. However, the broken-symmetry edge states have eluded spatial measurements. In this… 
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