Electric field gating of cadmium arsenide films using hexagonal boron nitride

ORAL

Abstract

Cadmium arsenide (Cd3As2) is a three-dimensional Dirac semimetal that also hosts exotic surface states connecting the projections of the Dirac nodes. Probing the electronic properties of thin films of Cd3As2 requires tuning of the Fermi level close to the Dirac nodes. Conventional gate dielectrics, such as Al2O3, must be deposited at low temperatures that do not exceed the stability limit of Cd3As2, which introduces a high density of (near) interface trap states that limit the modulation of carrier densities that can be achieved [1]. To address this problem, here we report on the use of hexagonal boron nitride (hBN) towards high-quality Cd3As2 devices. In addition to protecting the Cd3As2 channel from photoresist, the high breakdown voltage of hBN also allows us to tune the carrier density up to a larger range allowing us to explore new quantum states.

[1] O. F. Shoron, et al., Appl. Phys. Lett. 115, 062101 (2019)

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Presenters

  • Biswajit Datta

    • Materials, University of California, Santa Barbara
    • Materials Department, University of California, Santa Barbara

Authors

  • Biswajit Datta

    • Materials, University of California, Santa Barbara
    • Materials Department, University of California, Santa Barbara

  • Luca Galletti

    • Materials, UC Santa Barbara
    • Materials, University of California, Santa Barbara
    • University of California, Santa Barbara

  • Yu Saito

    • Physics, University of California, Santa Barbara
    • University of California, Santa Barbara
    • University of California at Santa Barbara, Santa Barbara, USA.

  • David Kealhofer

    • Physics, UC Santa Barbara
    • University of California, Santa Barbara
    • Materials, University of California, Santa Barbara

  • Manik Goyal

    • University of California, Santa Barbara
    • Materials, University of California, Santa Barbara

  • Omor F Shoron

    • Materials, University of California, Santa Barbara

  • Andrea Young

    • Physics, University of California, Santa Barbara
    • Department of Physics, University of California, Santa Barbara
    • University of California, Santa Barbara

  • Susanne Stemmer

    • Materials, UC Santa Barbara
    • University of California, Santa Barbara
    • Materials, University of California, Santa Barbara