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Magic continuum in twisted bilayer WSe2: Mott state and superconductivity

ORAL

Abstract

Emergent quantum phases driven by electronic interactions can manifest in materials with narrowly dispersing, i.e. “flat", energy bands. Recently, flat bands have been realized in a variety of graphene-based heterostructures using the tuning parameters of twist angle, layer stacking and pressure, and resulting in correlated insulator and superconducting states. Here we report the experimental observation of similar correlated phenomena in twisted bilayer tungsten diselenide (tWSe2), a semiconducting transition metal dichalcogenide (TMD). Unlike twisted bilayer graphene where the flat band appears only within a narrow range around a “magic angle", we observe correlated states over a continuum of angles, spanning 4° to 5.1°. Hall measurements supported by ab initio calculations suggest that the strength of the insulator is driven by the density of states at half filling, consistent with a 2D Hubbard model in a regime of moderate interactions. At 5.1° twist, we observe evidence of superconductivity upon doping away from half filling, reaching zero resistivity around 3 K. Our results establish twisted bilayer TMDs as a model system to study interaction-driven phenomena in flat bands with dynamically tunable interactions.
Reference: arXiV: 1910.12147

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Presenters

  • Lei Wang

    Columbia Univ, Physics, Columbia University, Physics, Nanjing University

Authors

  • Lei Wang

    Columbia Univ, Physics, Columbia University, Physics, Nanjing University

  • En-Min Shih

    Columbia University, Columbia Univ, Physics, Columbia University

  • Augusto Ghiotto

    Columbia University, Columbia Univ, Physics, Columbia University, Department of Physics, Columbia University

  • Lede Xian

    Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany, Max Planck Institute for the Structure and Dynamics of Matter, Structure and Dynamics of Matter, Max Planck Institute, Max Planck Inst Structure & Dynamics of Matter

  • Daniel A Rhodes

    Columbia University, Columbia Univ, Mechanical Engineering, Columbia University, Columbia University, NY, USA, Department of Mechanical Engineering, Columbia University

  • Cheng Tan

    Columbia Univ, Electrical Engineering, Columbia University, Mechanical Engineering, Columbia University

  • Martin Claassen

    Center for Computational Quantum Physics, The Flatiron Institute, Center for Computational Quantum Physics, Flatiron Institute

  • Dante M. Kennes

    RWTH Aachen University, Max Planck Institute for the Structure and Dynamics of Matter, Institut fur Theorie der Statistischen Physik, RWTH Aachen University

  • Yusong Bai

    Columbia University, Columbia Univ, Chemistry, Columbia University, Columbia University, Chemistry

  • Bumho kim

    Columbia Univ, Mechanical Engineering, Columbia University, Columbia University

  • Kenji Watanabe

    National Institute for Materials Science, Japan, National Institute for Material Science, National Institute for Materials Science, National Institute for Materials Science, Tsukuba, Research Center for Functional Materials, NIMS, nims, Advanced Materials Laboratory, National Institute for Materials Science, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, NIMS, National Institute for Material Science - Japan, NIMS Tsukuba, National Institute for Materials Science, Namiki 1-1, Ibaraki 305-0044, Japan., National Institute for Materials Science (NIMS), National Institute for Materials Science,Tsukuba, Ibaraki 305-0047, Japan, Advanced Materials Laboratory, NIMS, Japan, National Institute for Materials Science,1-1 Namiki, Tsukuba, 305-0044, Japan, National Institute of Materials Science, National Institute for Materials Science, University of Tsukuba, National Institute for Materials Science, Tsukuba, Japan, National Institute for Material Science, Japan, National Institue for Material Science, Tsukuba, Advanced Materials Laboratory, NIMS, Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba 305-0044, Japan, Advanced Matrials Lab, NIMS, National Institute for Material Science, Tsukuba, Japan, National institute for materials science, NIMS-Tsukuba, NIMS, Japan, National Institute for Materials Science, Namiki Tsukuba Ibaraki, Japan, NIRM, Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Japan, NIMS Japan, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan, Research Center for Functional Materials, National Institute for Materials Science, Tsukuba, Ibaraki, Japan, Advanced Materials Laboratory, National Institute of Materials Science, Advanced Materials Laboratory, National Institute for Materials Science 1-1 Namiki, Tsukuba, 305-0044, Japan, National Institute of Material Science, 1-1 Namiki, Tsukuba 305-0044, Japan, National Institute for Material Science (Japan), Physics, NIMS, National Institute of Materials Science, Japan, National Institute of Materials Science (NIMS), National Institute of Materials Science, Tsukuba, Ibaraki 305-0044, Japan, NIMS - Tsukuba

  • Takashi Taniguchi

    National Institute for Materials Science, Japan, National Institute for Material Science, National Institute for Materials Science, National Institute for Materials Science, Tsukuba, Research Center for Functional Materials, NIMS, nims, Advanced Materials Laboratory, National Institute for Materials Science, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, NIMS, National Institute for Material Science - Japan, NIMS Tsukuba, National Institute for Materials Science, Namiki 1-1, Ibaraki 305-0044, Japan., National Institute for Materials Science (NIMS), National Institute for Materials Science,Tsukuba, Ibaraki 305-0047, Japan, Advanced Materials Laboratory, NIMS, Japan, National Institute for Materials Science,1-1 Namiki, Tsukuba, 305-0044, Japan, National Institute of Materials Science, National Institute for Materials Science, University of Tsukuba, National Institute for Materials Science, Tsukuba, Japan, National Institue for Material Science, Tsukuba, Advanced Materials Laboratory, NIMS, Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba 305-0044, Japan, Advanced Matrials Lab, NIMS, National Institute for Material Science, Tsukuba, Japan, National institute for materials science, NIMS-Tsukuba, NIMS, Japan, National Institute for Materials Science, Namiki Tsukuba Ibaraki, Japan, Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Japan, NIMS Japan, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan, Research Center for Functional Materials, National Institute for Materials Science, Tsukuba, Ibaraki, Japan, Advanced Materials Laboratory, National Institute of Materials Science, Advanced Materials Laboratory, National Institute for Materials Science 1-1 Namiki, Tsukuba, 305-0044, Japan, National Institute of Material Science, 1-1 Namiki, Tsukuba 305-0044, Japan, National Institute for Material Science (Japan), Physics, NIMS, National Institute of Materials Science, Japan, National Institute of Materials Science, Tsukuba, Ibaraki 305-0044, Japan, NIMS - Tsukuba

  • Xiaoyang Zhu

    Columbia Univ, Chemistry, Columbia University, Columbia University, Chemistry, Columbia University, Department of Chemistry, Columbia University

  • James C Hone

    Columbia University, Mechanical Engineering, Columbia University, Columbia Univ, Physics, Columbia University, Columbia University, NY, USA, Department of Mechanical Engineering, Columbia University

  • Angel Rubio

    Theory Department, Max Planck Institute for the Structure and Dynamics of Matter, Center for Computational Quantum Physics (CCQ), The Flatiron Institute, Max Planck Institute for Structure and Dynamics of Matter, Department of Physics, Columbia University, New York, New York 10027, USA, Max Planck Institute for the Structure and Dynamics of Matter, Hamburg, Germany, Max Planck Institute for the Structure and Dynamics of Matter, Structure and Dynamics of Matter, Max Planck Institute, Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany, Max Planck Inst Structure & Dynamics of Matter, Max Planck Institue for the Structure and Dynamics of Matter, Theory, Max Planck Institute for the Structure & Dynamics of Matter

  • Abhay Pasupathy

    Columbia University, Physics Department, Columbia University, Columbia Univ, Department of Physics, Columbia University, New York, New York 10027, USA, Physics, Columbia University, Department of Physics, Columbia University

  • Cory Dean

    Department of Physics, Columbia University, Columbia University, Columbia Univ, Physics, Columbia University