Discovery of two-dimensional anisotropic superconductivity at KTaO<sub>3</sub> (111) interfaces

ORAL

Abstract

The unique electronic structure found at interfaces between materials can allow unconventional quantum states to emerge. One prominent example is the emergence of a superconducting electron gas at the interface of LaAlO3/SrTiO3. Here we observe superconductivity in electron gases formed at interfaces between (111) oriented KTaO3 and insulating overlayers of either EuO or LaAlO3. The superconducting transition temperature, approaching 2.2 K, is about one order of magnitude higher than that of the LaAlO3/SrTiO3 system. Strikingly, similar electron gases at (001) KTaO3 interfaces remain normal down to 25 mK. The critical field and IV measurements indicate that the superconductivity is two dimensional. Low carrier density EuO/KTaO3(111) samples, with higher mobilities, show spontaneous in-plane transport anisotropy at temperatues prior to the onset of global superconductivity, suggesting the emergence of a 'stripe' phase where the superconductivity is nearly homogeneous in one direction, but modulated in the other.
Reference: C. Liu et al., arXiv:2004.07416

*Supported by the US DOE, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division. The use of facilities at the CNM was supported by the DOE, Basic Energy Sciences under Contract No. DE-AC02-06CH11357.

Presenters

  • Changjiang Liu

    • Argonne National Laboratory
    • Materials Science Division, Argonne National Laboratory

Authors

  • Changjiang Liu

    • Argonne National Laboratory
    • Materials Science Division, Argonne National Laboratory
  • Xi Yan

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

    • Nanoscale Science and Technology Division, Argonne National Laboratory
  • Yang Ma

    • International Centre for Quantum Materials, School of Physics, Peking University
  • Haw-Wen Hsiao

    • University of Illinois at Urbana Champaign
    • Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign
  • Yulin Lin

    • Nanoscale Science and Technology Division, Argonne National Laboratory
  • Terence Bretz-Sullivan

    • Materials Science Division, Argonne National Laboratory
  • Xianjing Zhou

    • Nanoscale Science and Technology Division, Argonne National Laboratory
    • Argonne National Laboratory
  • John Pearson

    • Argonne National Laboratory
    • Materials Science Division, Argonne National Laboratory
    • Argonne National Lab
  • Brandon Fisher

    • Nanoscale Science and Technology Division, Argonne National Laboratory
    • Argonne National Laboratory
  • J Samuel Jiang

    • Argonne National Laboratory
    • Materials Science Division, Argonne National Laboratory
  • Wei Han

    • International Centre for Quantum Materials, School of Physics, Peking University
  • Jian-Min Zuo

    • Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign
  • Jianguo Wen

    • Center for Nanoscale Materials, Argonne National Laboratory
    • Nanoscale Science and Technology Division, Argonne National Laboratory
  • Dillon D Fong

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

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

    • X-ray Science Division, Advanced Photon Source,, Argonne National Laboratory
    • Advanced Photon Source, Argonne National Laboratory
    • Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
    • Argonne National Laboratory
    • Advanced Photon Source, Argonne National Lab
    • Advanced Photon Source
  • Anand Bhattacharya

    • Argonne National Laboratory
    • Materials Science Division, Argonne National Laboratory
    • Materials Science Division, Argonne National Lab