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arXiv · 1010.1187

Measurement of the ν= 1/3 fractional quantum Hall energy gap in suspended graphene

Fereshte Ghahari·Yue Zhao·Paul Cadden-Zimansky·Kirill Bolotin·Philip Kim
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Abstract

We report on magnetotransport measurements of multi-terminal suspended graphene devices. Fully developed integer quantum Hall states appear in magnetic fields as low as 2 T. At higher fields the formation of longitudinal resistance minima and transverse resistance plateaus are seen corresponding to fractional quantum Hall states, most strongly for ν= 1/3. By measuring the temperature dependence of these resistance minima, the energy gap for the 1/3 fractional state in graphene is determined to be at ~20 K at 14 T.

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Fereshte Ghahari, Yue Zhao, Paul Cadden-Zimansky, Kirill Bolotin, Philip Kim. 2011-02-07. Measurement of the ν= 1/3 fractional quantum Hall energy gap in suspended graphene. https://doi.org/10.1103/physrevlett.106.046801

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