Gateless and reversible carrier density tunability in epitaxial graphene devices functionalized with chromium tricarbonyl

ORAL

Abstract

Monolayer epitaxial graphene (EG) has been shown to have clearly superior properties for the development of quantized Hall resistance (QHR) standards. One major difficulty with QHR devices based on EG is that their electrical properties drift slowly over time if the device is stored in air due to adsorption of atmospheric molecular dopants. The crucial parameter for device stability is the charge carrier density, which determines the energy spacing of the Landau levels and thus the magnetic flux density required for precise QHR measurements. This work presents one solution to this problem of instability in air by functionalizing the surface of EG devices with chromium tricarbonyl - Cr(CO)3. Observations of carrier density stability in air over the course of one year are reported, as well as the ability to tune the carrier density by annealing the devices. For low temperature annealing, the presence of Cr(CO)3 stabilizes the electrical properties and allows for the reversible tuning of the carrier density in millimeter-scale graphene devices close to the Dirac point. Precision measurements in the quantum Hall regime show no detrimental effect on the carrier mobility.

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Presenters

  • Albert Rigosi

    National Institute of Standards and Technology, Quantum Measurement Division, National Institute of Standards and Technology, NIST

Authors

  • Albert Rigosi

    National Institute of Standards and Technology, Quantum Measurement Division, National Institute of Standards and Technology, NIST

  • Mattias Kruskopf

    National Institute of Standards and Technology, NIST

  • Heather M. Hill

    NIST, National Institute of Standards and Technology

  • Hanbyul Jin

    Quantum Measurement Division, National Institute of Standards and Technology, NIST, National Institute of Standards and Technology

  • Bi-Yi Wu

    Physics, National Taiwan University, National Institute of Standards and Technology

  • Philip E Johnson

    National Institute of Standards and Technology

  • Siyuan Zhang

    Theiss Research & NIST, National Institute of Standards and Technology

  • Michael Berilla

    National Institute of Standards and Technology

  • Angela Hight Walker

    NIST, Nanoscale Device Characterization Division, National Institute of Standards and Technology, National Institute of Standards and Technology, Nanoscale Device Characterization Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Nanoscale Spectroscopy Group, National Institute of Standards and Technology, Engineering Physics Division, National Institute of Standards and Technology

  • Christina Hacker

    National Institute of Standards and Technology

  • David B Newell

    National Institute of Standards and Technology, Quantum Measurement Division, National Institute of Standards and Technology

  • Randolph E Elmquist

    National Institute of Standards and Technology, NIST