Ferroelectric field and magnetic field effect on the spin-orbit coupled Mott insulator Sr<sub>2</sub>IrO<sub>4</sub>

ORAL

Abstract

The 4d and 5d transition metals are commonly characterized by a decreased Hubbard repulsion U which diminishes correlation effects, but simultaneously by an increased spin orbit coupling to create a new type of correlation effects which have been leading to such as spin-orbit coupled Mott insulators, Weyl semimetals, axion insulators and spin liquids. This rich physics allows small perturbations to create large effects in these strongly correlated materials. The Ruddlesden-Popper series of Srx+1IrxO3x+1 shows large differences in conductive behavior, where the n=∞ perovskite SrIrO3 is metallic while the n=1 Sr2IrO4 is an insulator due to a spin-orbit coupling band splitting to a Jeff=1/2 state. This state has many similarities to the high TC cuprate superconductors which show an S=1/2 state, which loses its antiferromagnetism and becomes superconducting upon hole doping. Likewise, theoretically it is argued that under electron doping it is possible to drive Sr2IrO4 superconducting. Here a ferroelectric field effect is used on ultrathin Sr2IrO4 films to drive it to a more metallic state, by playing on the competition between electron doping and the canted antiferromagnetic transition at ~200K.

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Presenters

  • Arnoud Everhardt

    • Materials Science and Engineering, University of California, Berkeley
    • Materials Sciences Division, Lawrence Berkeley National Laboratory
    • Materials Science Division, Lawrence Berkeley National Laboratory
    • Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands

Authors

  • Arnoud Everhardt

    • Materials Science and Engineering, University of California, Berkeley
    • Materials Sciences Division, Lawrence Berkeley National Laboratory
    • Materials Science Division, Lawrence Berkeley National Laboratory
    • Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands

  • Yun-Long Tang

    • Materials Sciences Division, Lawrence Berkeley National Laboratory
    • Department of Materials Science and Engineering, University of California, Berkeley

  • Xiaoxi Huang

    • Department of Materials Science and Engineering, University of California, Berkeley

  • Jay LeFebvre

    • University of California, Riverside

  • Shane Cybart

    • University of California, Riverside

  • R Ramesh

    • Department of Physics, University of California Berkeley, California, USA
    • Department of Materials Science and Engineering, University of California at Berkeley
    • Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.
    • Department of Materials Science and Engineering, University of California, Berkeley
    • Department of Physics, University of California, Berkeley