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arXiv · 1805.04199

Quantitative transport measurements of fractional quantum Hall energy gaps in edgeless graphene devices

Hryhoriy Polshyn·Haoxin Zhou·Eric. M. Spanton·Takashi Taniguchi·Kenji Watanabe·Andrea F. Young
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Abstract

Owing to their wide tunability, spin- and valley internal degrees of freedom, and low disorder, graphene heterostructures are emerging as a promising experimental platform for fractional quantum Hall (FQH) studies. Surprisingly, however, transport measurements reveal many fewer FQH states than bulk capacitive probes. Here, we report the fabrication of dual graphite-gated monolayer graphene devices in an edgeless Corbino-type geometry that showing deep FQH sequences. Thermal activation gaps reveal a tunable crossover between single- and multi-component FQH states in the zero energy Landau level, while the first Landau level is found to host an unexpected valley-ordered state at $\nu=-4$.

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Hryhoriy Polshyn, Haoxin Zhou, Eric. M. Spanton, Takashi Taniguchi, Kenji Watanabe, Andrea F. Young. 2018-05-10. Quantitative transport measurements of fractional quantum Hall energy gaps in edgeless graphene devices. https://doi.org/10.1103/physrevlett.121.226801

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