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arXiv · 0909.2903

Half integer quantum Hall effect in high mobility single layer epitaxial graphene

Xiaosong Wu·Yike Hu·Ming Ruan·Nerasoa K Madiomanana·John Hankinson·Mike Sprinkle·Claire Berger·Walt A. de Heer
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Abstract

The quantum Hall effect, with a Berry's phase of $π$ is demonstrated here on a single graphene layer grown on the C-face of 4H silicon carbide. The mobility is $\sim$ 20,000 cm$^2$/V$\cdot$s at 4 K and ~15,000 cm$^2$/V$\cdot$s at 300 K despite contamination and substrate steps. This is comparable to the best exfoliated graphene flakes on SiO$_2$ and an order of magnitude larger than Si-face epitaxial graphene monolayers. These and other properties indicate that C-face epitaxial graphene is a viable platform for graphene-based electronics.

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Xiaosong Wu, Yike Hu, Ming Ruan, Nerasoa K Madiomanana, John Hankinson, Mike Sprinkle, Claire Berger, Walt A. de Heer. 2009-12-08. Half integer quantum Hall effect in high mobility single layer epitaxial graphene. https://doi.org/10.1063/1.3266524

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