<i>In Situ</i>, Monolayer Control over the 2D Electron Gas on SrTiO<sub>3</sub>

ORAL

Abstract

SrTiO3 (001) is the principal material in the field of oxide electronics, due to both its properties and the fact that the composition of its surface can be controlled, leading to TiO2 surface termination. Employing in situ synchrotron X-ray methods during growth by molecular beam epitaxy (MBE) and angle-resolved photoemission spectroscopy (ARPES), we discover the existence of a 2D electron gas (2DEG) at the as-prepared, TiO2-terminated SrTiO3 (001) surface. Interestingly, the 2DEG appears correlated with the presence of a TiO2 double layer [S. Cook et al., Sci. Adv. 5, eaav0764 (2019).], as deposition of single layer of SrO leads to island formation and complete elimination of the 2DEG. The subsequent growth of a TiO2 monolayer leads to smoothing and return of the 2DEG. We will provide an atomic-level description of the evolving surface and how it relates to the surface electronic structure.

*Work supported by the Department of Energy, Office of Science, Basic Energy Sciences under contract no. DE-AC02-06CH11357.

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Presenters

  • Xi Yan

    • Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA

Authors

  • Xi Yan

    • Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA

  • Friederike Wrobel

    • Argonne Natl Lab
    • Max Planck Institute for Solid State Research
    • Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA

  • Hawoong Hong

    • Argonne Natl Lab
    • Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
    • Argonne National Laboratory

  • Jirong Sun

    • Chinese Academy of Sciences,Institute of Physics
    • Beijing National Laboratory for Condensed Matter & Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China

  • Jessica L McChesney

    • Advanced Photon Source, Argonne National Laboratory
    • Advanced Photon Source
    • Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA

  • Hua Zhou

    • Advanced Photon Source, Argonne National Laboratory, Argonne, IL, USA
    • Advanced Photon Source, Argonne National Laboratory
    • Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA

  • Dillon Fong

    • Argonne Natl Lab
    • Materials Science Division, Argonne National Laboratory
    • Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA