Systematic analysis of superconductivity in magic-angle twister bilayer graphene nanodevices

ORAL

Abstract

Superconductivity and correlated insulating states have recently been observed in ‘magic-angle’ twisted bilayer graphene heterostructures at twist angles close to 1.1 degrees, featuring nearly-flat bands owing to strong interlayer coupling. We here perform a systematic study of superconductivity and correlated phenomena in more than 10 different superconducting devices with angles comprised between 0.99 degrees and 1.19 degrees. Angle dependence of critical temperature and field, together with the interplay between superconductivity and insulating states, are examined. Higher quality devices allow us to extend the analysis to superconductivity when doping the twisted bilayer system with electrons. This 2D superconductor, based on graphene moiré superlattices, offers a uniquely tunable, clean and relatively simple platform for the investigation of strongly correlated physics.

*This work has been primarily supported by the National Science Foundation (DMR-1809802) and the Gordon and Betty Moore Foundation's EPiQS Initiative through Grant GBMF4541 for device fabrication, transport measurements, and data analysis. DRL acknowledges support from Obra Social “la Caixa” Fellowship.

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Presenters

  • Daniel Rodan Legrain

    • Department of Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology
    • Physics, Massachusetts Institute of Technology
    • Dept. of Physics, Massachusetts Institute of Technology, USA

Authors

  • Daniel Rodan Legrain

    • Department of Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology
    • Physics, Massachusetts Institute of Technology
    • Dept. of Physics, Massachusetts Institute of Technology, USA

  • Yuan Cao

    • Department of Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology

  • Oriol Rubies-Bigorda

    • Department of Physics, Massachusetts Institute of Technology
    • Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology

  • Valla Fatemi

    • Department of Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology
    • Yale Univ
    • Applied Physics, Yale University
    • Department of Applied Physics, Yale University

  • Shiang Fang

    • Department of Physics, Harvard University
    • Physics, Harvard University
    • Harvard University

  • Kenji Watanabe

    • National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305 0044, Japan
    • Advanced Materials Laboratory, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Materials Science
    • Advanced Materials Laboratory, National Institute for Materials Science, , 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Material Science, 1-1 Namiki, Tsukuba 305-0044
    • National Institute of Materials Science
    • NIMS, Japan
    • Advanced Materials Laboratory, NIMS
    • National Institute for Materials Science, Tsukuba, Japan
    • National Institute for Materials Science, Japan
    • Advanced Materials Laboratory, National Institute for Materials Science
    • National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0044, Japan
    • National Institute for Materials Science (NIMS)
    • NIMS Tsukuba
    • National Institute for Materials Science (Japan)
    • NIMS
    • National Institute for Material Science
    • National Institute for Materials Science, 1-1 Namiki, Tsukuba, Japan
    • National Institute for Materials Science , Japan
    • National Institute for Materials Science, Namiki 1-1, Tsukuba, Ibaraki 305-0044, Japan.
    • Advanced Materials Laboratory, National Institute for Materials Science, Japan
    • Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan
    • National Institute for Materials Science, Tsukuba, Ibaraki 305- 0044, Japan
    • National Institute for Material Science - Japan
    • National Institute for Materials Science, Namiki Tsukuba Ibaraki, Japan
    • National Institute of Material Science
    • Advanced Material Lab, NIMS
    • Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Japan
    • Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Ibaraki, Japan
    • National Institute for Materials Science, Tsukuba
    • 1-1 Namiki, Tsukuba, National Institute for Materials Science
    • NIMS/Tsukuba
    • National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044 Japan
    • National Institute for Materials Science, Namiki, 305-0044, Japan
    • National Institute for Material Science, Japan
    • Advanced Materials Laboratory, NIMS, Japan
    • Columbia University
    • Advanced Materials Labaratory, National Institute for Materials Science
    • National Institute of Material Science, 1-1 Namiki, Tsukuba, Ibaraki 205-0044, Japan
    • National Institute of Materials Science, Japan

  • Takashi Taniguchi

    • National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305 0044, Japan
    • National Institute for Materials Science
    • Advanced Materials Laboratory, National Institute for Materials Science, , 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Material Science, 1-1 Namiki, Tsukuba 305-0044
    • National Institute of Materials Science
    • NIMS, Japan
    • Advanced Materials Laboratory, NIMS
    • National Institute for Materials Science, Tsukuba, Japan
    • Advanced Materials Laboratory, National Institute for Materials Science
    • National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0044, Japan
    • National Institute for Materials Science (NIMS)
    • NIMS Tsukuba
    • NIMS
    • National Institute for Material Science
    • National Institute for Materials Science, Japan
    • National Institute for Materials Science, 1-1 Namiki, Tsukuba, Japan
    • National Institute for Materials Science , Japan
    • Advanced Materials Laboratory, National Institute for Materials Science, Japan
    • Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan
    • National Institute for Materials Science, Tsukuba, Ibaraki 305- 0044, Japan
    • National Institute for Material Science - Japan
    • National Institute for Materials Science, Namiki Tsukuba Ibaraki, Japan
    • National Institute of Material Science
    • Advanced Material Lab, NIMS
    • Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Japan
    • Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Ibaraki, Japan
    • National Institute for Materials Science, Tsukuba
    • 1-1 Namiki, Tsukuba, National Institute for Materials Science
    • NIMS/Tsukuba
    • National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044 Japan
    • National Institute for Materials Science, Namiki, 305-0044, Japan
    • National Institute for Material Science, Japan
    • Advanced Materials Laboratory, NIMS, Japan
    • Advanced Materials Labaratory, National Institute for Materials Science
    • National Institute of Material Science, 1-1 Namiki, Tsukuba, Ibaraki 205-0044, Japan
    • National Institute of Materials Science, Japan

  • Efthimios Kaxiras

    • Harvard University
    • Department of Physics, Harvard University
    • Physics, Harvard University

  • Pablo Jarillo-Herrero

    • Physics, Massachusetts Institute of Technology
    • Department of Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology
    • Dept. of Physics, Massachusetts Institute of Technology, USA
    • Massachusetts Inst of Tech-MIT
    • Physics, MIT