Giant magnetic response of a two-dimensional antiferromagnetic iridate

ORAL

Abstract

Layered iridates are featured of preserving a hidden SU(2) symmetry such that anisotropic exchange interactions have no contribution to spin anisotropy. Achieving this symmetry, however, is highly challenging because it's necessary to incorporate strong spin-orbit coupling, control the 2D lattice structure, and minimize the interlayer coupling. We solved this issue through top-down design and bottom-up synthesis of SrIrO3 and SrTiO3 superlattices [1] to realize a pseudospin-half antiferromagnetic (AFM) square lattice. We observed giant AFM responses to sub-tesla external fields by exploiting the strong 2D critical fluctuations preserved under the symmetry-invariant exchange anisotropy. The observed field-induced logarithmic increase of the ordering demonstrates a new pathway for the highly efficient control of AFM order [2]. Further investigation on the transport properties suggests a novel coupling between AFM fluctuations and charge fluctuations, highlights the application potential in semiconductor devices.
[1] L. Hao, et.al. Phys. Rev. Lett. 119, 027204 (2017).
[2] L. Hao, et.al. Nat. Phys. 14, 806–810 (2018).

*J.L. acknowledges support by the Organized Research Unit Program at the University of Tennessee and support by the DOD-DARPA under grant no. HR0011-16-1-0005.

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Presenters

  • Lin Hao

    • Physics, University of Tennessee
    • Department of Physics and Astronomy, University of Tennessee
    • Department of Physics and Astronomy, University of Tennesse

Authors

  • Lin Hao

    • Physics, University of Tennessee
    • Department of Physics and Astronomy, University of Tennessee
    • Department of Physics and Astronomy, University of Tennesse

  • Derek Meyers

    • Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory
    • Materials Science and Engineering, University of California, Berkeley
    • Brookhaven National Laboratory

  • Hidemaro Suwa

    • Department of Physics and Astronomy, University of Tennessee

  • Junyi Yang

    • Department of Physics and Astronomy, University of Tennessee

  • tamene R. Dasa

    • Department of Materials Science and Engineering, University of Tennessee

  • Haixuan Xu

    • University of Tennessee
    • Department of Materials Science and Engineering, University of Tennessee
    • Materials Science and Engineering, Univ of Tennessee, Knoxville

  • Cristian Batista

    • Department of Physics & Astronomy, University of Tennessee, Knoxville, TN 37996, USA
    • Department of Physics and Astronomy, The University of Tennessee
    • University of Tennessee
    • Department of Physics and Astronomy, University of Tennessee
    • Department of Physics, University of Tennessee

  • Mark Dean

    • Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory
    • Department of Condensed Matter Physics and Materials Science, Upton, New York 11973, USA, Brookhaven National Laboratory
    • BNL
    • Brookhaven National Laboratory
    • Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory

  • Jian Liu

    • University of Tennessee
    • Physics, University of Tennessee
    • Department of Physics and Astronomy, University of Tennessee
    • Physics and Astronomy, Univ of Tennessee, Knoxville
    • Department of Physics, University of Tennessee, Knoxville
    • University of Tennesse
    • Department of Physics and Astronomy, University of Tennesse