Quantum transport in Dirac semimetal Cd3As2 thin films

ORAL

Abstract

The synthesis of thin films of the Dirac semimetal (DSM) Cd3As2 by molecular beam epitaxy (MBE) provides an attractive avenue for studying quantum transport in a DSM as a function of quantum confinement and chemical potential. We have used MBE to grow thin films of Cd3As2 on GaAs (111)B substrates with a GaSb buffer layer. The film thickness is varied in the range of 7 nm – 20 nm. Atomic force microscopy, x-ray diffraction, and electrical transport show that the films have good crystalline quality (root mean square surface roughness ~ 1.5 nm and full-width half maximum of rocking curves ~ 0.12°) and reasonable electron mobility (5,000 – 40,000 cm2/V.s at 4.2 K). We have studied Shubnikov-de Haas oscillations in lithographically patterned top gated Hall bar devices as a function of gate voltage, temperature, and magnetic field magnitude/angle. We interpret these quantum oscillation data in concert with in vacuo angle-resolved photoemission spectroscopy and first-principles calculations to gain insight into the Fermi surface of these DSM thin films.

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Presenters

  • Run Xiao

    Pennsylvania State University, Physics, Pennsylvania State University

Authors

  • Run Xiao

    Pennsylvania State University, Physics, Pennsylvania State University

  • Sayak Ghosh

    Cornell University

  • Arpita Mitra

    Pennsylvania State University

  • Wilson Yanez

    Pennsylvania State University, Physics, Pennsylvania State University

  • Timothy S Pillsbury

    Pennsylvania State University, Physics, The Pennsylvania State University, Physics, Pennsylvania State University, The Pennsylvania State University

  • Yawen Fang

    Cornell University

  • Juan Chamorro

    Johns Hopkins University

  • Santu Baidya

    Rutgers University, Rutgers University, New Brunswick, Department of Physics and Astronomy, Rutgers University

  • Tanya Berry

    Johns Hopkins University, The Johns Hopkins University

  • David Vanderbilt

    Rutgers University, New Brunswick, Rutgers University, Physics, Rutger Univeristy, Department of Physics and Astronomy, Rutgers University, Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, USA

  • Yi Li

    Johns Hopkins University

  • Tyrel McQueen

    Johns Hopkins University, The Johns Hopkins University, Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University

  • Brad Ramshaw

    Cornell University, Physics, Cornell University

  • Nitin Samarth

    Pennsylvania State University, Department of Physics, The Pennsylvania State University, Physics, The Pennsylvania State University, Physics, Pennsylvania State University, The Pennsylvania State University