Square to trigonal symmetry and itinerant to localized magnetism in ultra-thin SrRuO<sub>3</sub> films

ORAL

Abstract

Transition metal oxides perovskites (ABO3) along [111] direction consists of alternating AO3 and B planes. The B sites form a triangular lattice and two such pseudo-cubic unit cells (ABO3) form a buckled honeycomb lattice. This provides an opportunity of creating a graphene-like structure with d-electron system and is predicted to give rise to novel quantum phases. In this work, thin films of SrRuO3 (SRO) are grown in [001] and [111] direction and their electronic and magnetic properties are investigated as a function of film thickness. Metal-insulator transition is observed at a thickness of ~3 and ~7 unit cells in SRO (001) and SRO (111), respectively. While ferromagnetism (FM) and metallicity occur concurrently in SRO (001), FM in ultrathin SRO(111) precedes metallicity which is surprising since SRO has traditionally been described as a Stoner FM. This can be related to the magnetic sublattice symmetry and more pronounced role of localized moments in SRO(111). Our study highlights the possible breakdown of itinerant magnetism picture in trigonal symmetry and the role of structure on an atomic scale will be discussed.

*Supported by:
US National Science Foundation (DMR1608865)
US Department of Energy (DE-SC0002136)

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Presenters

  • Prahald Siwakoti

    • Department of Physics and Astronomy, Louisiana State University
    • Louisiana State University

Authors

  • Prahald Siwakoti

    • Department of Physics and Astronomy, Louisiana State University
    • Louisiana State University

  • Mohammad Saghayezhian

    • Department of Physics and Astronomy, Louisiana State University
    • Louisiana State University

  • Zhen Wang

    • Department of Physics and Astronomy, Louisiana State University
    • Condensed Matter Physics & Materials Science Department, Brookhaven National Lab

  • David Howe

    • Louisiana State University
    • Department of Physics and Astronomy, Louisiana State University

  • Zeeshan Ali

    • Department of Physics and Astronomy, Louisiana State University

  • Yimei Zhu

    • Brookhaven National Laboratory
    • Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory
    • Condensed Matter Physics & Materials Science Department, Brookhaven National Lab
    • Condensed Matter Physics & Materials Science Department, Brookhaven National Laboratory
    • Condensed Matter Physics, Brookhaven National Laboratory

  • Jiandi Zhang

    • Department of Physics and Astronomy, Louisiana State University
    • Louisiana State University