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arXiv · 0912.2791

Dependence of quantum-Hall conductance on the edge-state equilibration position in a bipolar graphene sheet

Dong-Keun Ki·Seung-Geol Nam·Hu-Jong Lee·Barbaros Oezyilmaz
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Abstract

By using four-terminal configurations, we investigated the dependence of longitudinal and diagonal resistances of a graphene p-n interface on the quantum-Hall edge-state equilibration position. The resistance of a p-n device in our four-terminal scheme is asymmetric with respect to the zero point where the filling factor ($ν$) of the entire graphene vanishes. This resistance asymmetry is caused by the chiral-direction-dependent change of the equilibration position and leads to a deeper insight into the equilibration process of the quantum-Hall edge states in a bipolar graphene system.

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Dong-Keun Ki, Seung-Geol Nam, Hu-Jong Lee, Barbaros Oezyilmaz. 2009-12-15. Dependence of quantum-Hall conductance on the edge-state equilibration position in a bipolar graphene sheet. https://doi.org/10.1103/physrevb.81.033301

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