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arXiv · 0905.0746

Observation of chiral quantum-Hall edge states in graphene

Dong-Keun Ki·Sanghyun Jo·Hu-Jong Lee
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Abstract

In this study, we determined the chiral direction of the quantum-Hall (QH) edge states in graphene by adopting simple two-terminal conductance measurements while grounding different edge positions of the sample. The edge state with a smaller filling factor is found to more strongly interact with the electric contacts. This simple method can be conveniently used to investigate the chirality of the QH edge state with zero filling factor in graphene, which is important to understand the symmetry breaking sequence in high magnetic fields ($\gtrsim$25 T).

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Dong-Keun Ki, Sanghyun Jo, Hu-Jong Lee. 2009-05-06. Observation of chiral quantum-Hall edge states in graphene. https://doi.org/10.1063/1.3123265

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