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arXiv · 2002.01123

Extraordinary magnetoresistance in encapsulated monolayer graphene devices

Bowen Zhou·Kenji Watanabe·Takashi Taniguchi·Erik A. Henriksen
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Abstract

We report a proof-of-concept study of extraordinary magnetoresistance (EMR) in devices of monolayer graphene encapsulated in hexagonal boron nitride, having metallic edge contacts and a central metal shunt. Extremely large EMR values, $MR=(R(B) - R_0) / R_0\sim 10^5$, are achieved in part because $R_0$ approaches or crosses zero as a function of the gate voltage, exceeding that achieved in high mobility bulk semiconductor devices. We highlight the sensitivity, $dR/dB$, which in two-terminal measurements is the highest yet reported for EMR devices, and in particular exceeds prior results in graphene-based devices by a factor of 20. An asymmetry in the zero-field transport is traced to the presence of $pn$-junctions at the graphene-metal shunt interface.

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Bowen Zhou, Kenji Watanabe, Takashi Taniguchi, Erik A. Henriksen. 2020-02-04. Extraordinary magnetoresistance in encapsulated monolayer graphene devices. https://doi.org/10.1063/1.5142021

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