Suppression of weak ferromagnetism in ultra-thin iridates by interfacial engineering of octahedral rotations

POSTER

Abstract

The 5d transition metal oxide Sr2IrO4 has been predicted to be a new type of high-Tc superconductor upon electron doping, and exhibits many behaviors similar to cuprates. However, no direct evidences (zero resistance and Meissner effects) of superconductivity have been observed up to date. A major difference between irdates and cuprates is the sizable IrO6 octahedral rotations and weak ferromagnetic ordering (considerable net magnetic moments) in the IrO2 plane, which may hinder the formation of cooper pairing. To suppress the IrO6 octahedral rotations, we grew epitaxial SrIrO3 films on cubic SrTiO3 substrate by reactive molecular-beam epitaxy. Via the interfacial clamping effect imposed by substrates, low-energy electron diffraction (LEED) measurements exhibit no octahedral rotations in 2 and 1 unit-cell SrIrO3 films. In-situ angle-resolved photoemission spectroscopy (ARPES) and first principle calculations suggest an intriguing antiferromagnetic ground state with no canted magnetic moments in these ultra-thin SrIrO3 films. Our work provides a new path to explore superconductivity in iridates.

*This work was supported by the National Basic Research Program of China (2015CB654901), the National Science Founda- tion of China (11774153, 11574135).

Presenters

  • Wei Guo

    • National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, and Collaborative Innovation Center of Advanced Microstructures, Nanjing Unive

Authors

  • Wei Guo

    • National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, and Collaborative Innovation Center of Advanced Microstructures, Nanjing Unive

  • Dianxiang Ji

    • National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, and Collaborative Innovation Center of Advanced Microstructures, Nanjing Unive

  • Zhengbin Gu

    • National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, and Collaborative Innovation Center of Advanced Microstructures, Nanjing Unive

  • jian zhou

    • National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, and Collaborative Innovation Center of Advanced Microstructures, Nanjing Unive
    • Nanjing University

  • Yuefeng Nie

    • National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, and Collaborative Innovation Center of Advanced Microstructures, Nanjing Unive

  • Xiaoqing Pan

    • University of California
    • Departments of Chemical Engineering and Materials Science and Department of Physics and Astronomy, University of California
    • Department of Chemical Engineering and Materials Science and Department of Physics and Astronomy, University of California