Título
Topological valley currents via ballistic edge modes in graphene superlattices near the primary Dirac point
Autor(es)
Palabras clave
Graphene superlattices
Primary Dirac point
Fecha de publicación
2020
Editor
Springer Nature
Citación
Li, Y., Amado, M., Hyart, T. et al. Topological valley currents via ballistic edge modes in graphene superlattices near the primary Dirac point. Commun Phys 3, 224 (2020). https://doi.org/10.1038/s42005-020-00495-y
Resumen
[EN]Graphene on hexagonal boron nitride (hBN) can exhibit a topological phase via mutual crystallographic alignment. Recent measurements of nonlocal resistance (Rnl) near the secondary Dirac point (SDP) in ballistic graphene/hBN superlattices have been interpreted as arising due to the quantum valley Hall state. We report hBN/graphene/hBN superlattices in which Rnl at SDP is negligible, but below 60 K approaches the value of h/2e2 in zero magnetic field at the primary Dirac point with a characteristic decay length of 2 μm. Furthermore, nonlocal transport transmission probabilities based on the Landauer-Büttiker formalism show evidence for spin-degenerate ballistic valley-helical edge modes, which are key for the development of valleytronics.
URI
DOI
10.1038/s42005-020-00495-y
Versión del editor
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