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arXiv · 1410.2024

Bilayer-induced asymmetric quantum Hall effect in epitaxial graphene

Andrea Iagallo·Shinichi Tanabe·Stefano Roddaro·Makoto Takamura·Yoshiaki Sekine·Hiroki Hibino·Vaidotas Miseikis·Camilla Coletti·Vincenzo Piazza·Fabio Beltram·Stefan Heun
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Abstract

The transport properties of epitaxial graphene on SiC(0001) at quantizing magnetic fields are investigated. Devices patterned perpendicularly to SiC terraces clearly exhibit bilayer inclusions distributed along the substrate step edges. We show that the transport properties in the quantum Hall regime are heavily affected by the presence of bilayer inclusions, and observe a significant departure from the conventional quantum Hall characteristics. A quantitative model involving enhanced inter-channel scattering mediated by the presence of bilayer inclusions is presented that successfully explains the observed symmetry properties.

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Andrea Iagallo, Shinichi Tanabe, Stefano Roddaro, Makoto Takamura, Yoshiaki Sekine, Hiroki Hibino, Vaidotas Miseikis, Camilla Coletti, Vincenzo Piazza, Fabio Beltram, Stefan Heun. 2014-10-14. Bilayer-induced asymmetric quantum Hall effect in epitaxial graphene. https://doi.org/10.1088/0268-1242%2F30%2F5%2F055007

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