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arXiv · 1401.1796

Friedel Oscillation-Induced Energy Gap Manifested as Transport Asymmetry at Monolayer-Bilayer Graphene Boundaries

Kendal W. Clark·X. -G. Zhang·Gong Gu·Jewook Park·Guowei He·R. M. Feenstra·An-Ping Li
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Abstract

We show that Friedel charge oscillation near an interface opens a gap at the Fermi energy for electrons with wave vectors perpendicular to the interface. If the Friedel gaps on two sides of the interface are different, a nonequlibrium effect - shifting of these gaps under bias - leads to asymmetric transport upon reversing the bias polarity. The predicted transport asymmetry is revealed by scanning tunneling potentiometry at monolayer-bilayer interfaces in epitaxial graphene on SiC (0001). This intriguing interfacial transport behavior opens a new avenue towards novel quantum functions such as quantum switching.

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Kendal W. Clark, X. -G. Zhang, Gong Gu, Jewook Park, Guowei He, R. M. Feenstra, An-Ping Li. 2014-01-08. Friedel Oscillation-Induced Energy Gap Manifested as Transport Asymmetry at Monolayer-Bilayer Graphene Boundaries. https://doi.org/10.1103/physrevx.4.011021

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