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DOE OSTI · 1994761

Graphene-Based Quantum Hall Interferometer with Self-Aligned Side Gates

Zhao, Lingfei·Arnault, Ethan G.·Larson, Trevyn F. Q.·Iftikhar, Zubair·Seredinski, Andrew·Fleming, Tate·Watanabe, Kenji·Taniguchi, Takashi·Amet, François·Finkelstein, Gleb
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Abstract

The vanishing band gap of graphene has long presented challenges for fabricating high-quality quantum point contacts (QPCs)–the partially transparent p-n interfaces introduced by conventional split-gates tend to short the QPC. This complication has hindered the fabrication of graphene quantum Hall Fabry-P'erot interferometers, until recent advances have allowed split-gate QPCs to operate utilizing the highly resistive ν = 0 state. Here, we present a simple recipe to fabricate QPCs by etching a narrow trench in the graphene sheet to separate the conducting channel from self-aligned graphene side gates. Finally, we demonstrate operation of the individual QPCs in the quantum Hall regime, and further utilize these QPCs to create and study a quantum Hall interferometer.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY77 NANOSCIENCE AND NANOTECHNOLOGYgrapheneinterferometerquantum Hallquantum Hall interferometerquantum point contactsside gates

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Zhao, Lingfei, Arnault, Ethan G., Larson, Trevyn F. Q., Iftikhar, Zubair, Seredinski, Andrew, Fleming, Tate, Watanabe, Kenji, Taniguchi, Takashi, Amet, François, Finkelstein, Gleb. 2022-11-28. Graphene-Based Quantum Hall Interferometer with Self-Aligned Side Gates. https://doi.org/10.1021/acs.nanolett.2c03805

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