Topological valley transport at bilayer graphene domain walls

  title={Topological valley transport at bilayer graphene domain walls},
  author={Long Ju and Zhiwen Shi and Nityan L. Nair and Yinchuan Lv and Chenhao Jin and Jairo Velasco and Claudia Ojeda-Aristizabal and Hans A. Bechtel and Michael C. Martin and Alex Zettl and James G. Analytis and Feng Wang},
Electron valley, a degree of freedom that is analogous to spin, can lead to novel topological phases in bilayer graphene. A tunable bandgap can be induced in bilayer graphene by an external electric field, and such gapped bilayer graphene is predicted to be a topological insulating phase protected by no-valley mixing symmetry, featuring quantum valley Hall effects and chiral edge states. Observation of such chiral edge states, however, is challenging because inter-valley scattering is induced… 

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