Charge sensing of an unconventional ferroelectric metal in bilayer graphene

ORAL

Abstract

Moiré superlattices in twisted and lattice-mismatched van der Waals systems have recently led to a dazzling display of correlated phenomena including superconductivity, magnetism, and correlated insulating states. Here, we show that Bernal-stacked bilayer graphene in moiré superlattices with insulating boron nitride can result in a surprising electronically-driven ferroelectric state, exhibiting dramatic and unconventional hysteresis in transport and capacitive charge sensing. This ferroelectricity manifests as a robust and switchable electric polarization that coexists with metallicity, unexpected for this well-studied system. By measuring capacitances between the bilayer graphene and the top and bottom gates separately, we find large layer-asymmetric charge compressibility arising from an electronic phase transition. Moiré structures of Bernal-stacked bilayer graphene thus offer a new paradigm for exploring emergent electronic correlations and spontaneous symmetry breaking in an ultraclean two-dimensional system.

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Presenters

  • Sergio de la Barrera

    Massachusetts Institute of Technology MIT, Physics, Massachusetts Institute of Technology

Authors

  • Sergio de la Barrera

    Massachusetts Institute of Technology MIT, Physics, Massachusetts Institute of Technology

  • Zhiren Zheng

    Massachusetts Institute of Technology MIT

  • Qiong Ma

    Massachusetts Institute of Technology MIT

  • Zhen Bi

    Massachusetts Institute of Technology MIT

  • Ming-hao Liu

    National Cheng Kung University

  • Nannan Mao

    Massachusetts Institute of Technology MIT

  • Yang Zhang

    Massachusetts Institute of Technology MIT, Massachusetts Institute of Technology

  • Natasha Kiper

    Massachusetts Institute of Technology MIT

  • Kenji Watanabe

    National Institute for Materials Science, National Institute for Materials Science, Japan, National Institure for Materials Science, Advanced Materials Laboratory, National Institute for Materials Science, NIMS, National Institute of Materials Science, National Institute for Materials Science (NIMS), Research Center for Functional Materials, National Institute for Materials Science, National Institute for Materials Science,1-1 Namiki, National Institute of Material Science, National Institute for Materials Science, Tsukuba, Japan, Research Center for Functional Materials, NIMS, National Institute of Materials Science, Tsukuba, Japan, National Institude for Materials Science, National Institute for Materials Science, Tsukuba, Ibaraki, Japan, Research Center for Functional Materials, National Institute for Materials Science, Tsukuba 305-0044, Japan, International Center for Materials Nanoarchitectonics, National Institute for Materials, NIMS - Japan, National Institute for Materials Science ,Japan, National Institute for Materials Science, Tsukuba, 305-0044, Ibaraki, Japan, National Institute for Material Science, National Institute for Material Science, 1-1 Namiki, Tsukuba 305-0044, Japan, National Institute for Material Science Japan, NIMS Tsukuba, National Institute for Materials Science, Research Center for Functional Materials, Japan, Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, National Institute for Materials Science: Namiki, Tsukuba, Ibaraki, JP, National Institue for Material Science, National Institute for Materials Science,1-1 Namiki, Tsukuba, 305-0044, Japan, Materials, NIMS, Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, Research Center for Functional Materials, National In, Research Center for Functional Materials, Japan, International Center for Materials Nanoarchitectonics, National Institute for Materials Science, International Center for Materials nanoarchtectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan, NIMS Suguba, NIMS, Tsukuba, Japan, National Institute for Materials Science, Namiki 1-1, Tsukuba, 305-0044, Ibaraki, Japan, National institute of material science, Advanced Materials Laboratory, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan, Advanced Materials Laboratory, NIMS, Research Center for Functional Materials, National Institute for Materials Science, Ibaraki, Japan, National Institute for Materials Science, Research Center for Functional Materials, National Institute of Material Science, Japan, Tsukuba, National Institute for Materials Science

  • Takashi Taniguchi

    National Institute for Materials Science, National Institute for Materials Science, Japan, National Institure for Materials Science, Advanced Materials Laboratory, National Institute for Materials Science, NIMS, National Institute of Materials Science, National Institute for Materials Science (NIMS), International Center for Materials Nanoarchitectonics, National Institute for Materials Science, National Institute for Materials Science,1-1 Namiki, National Institute of Material Science, National Institute for Materials Science, Tsukuba, Japan, International Center for Materials Nanoarchitectonics, NIMS, Research Center for Functional Materials, National Institute for Materials Science, National Institute of Materials Science, Tsukuba, Japan, National Institude for Materials Science, International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba 305-0044, Japan, International Center for Materials Nanoarchitectonics, National Institute for Materials, NIMS - Japan, National Institute for Materials Science ,Japan, National Institute for Materials Science, Tsukuba, 305-0044, Ibaraki, Japan, National Institute for Material Science, National Institute for Material Science, 1-1 Namiki, Tsukuba 305-0044, Japan, National Institute for Material Science Japan, 8International Center for Materials Nanoarchitectonics, NIMS Tsukuba, National Institute for Materials Science: Namiki, Tsukuba, Ibaraki, JP, National Institue for Material Science, National Institute for Materials Science,1-1 Namiki, Tsukuba, 305-0044, Japan, Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, Research Center for Functional Materials, National In, Research Center for Functional Materials, Japan, Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan, International Center for Material Nanoarchitectonics, National Institute for Materials Science, International Center for Materials Nanoarchitectonics, NIMS Suguba, NIMS, Tsukuba, Japan, National Cheng Kung University, National Institute for Materials Science, Namiki 1-1, Tsukuba, 305-0044, Ibaraki, Japan, National institute of material science, Advanced Materials Laboratory, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan, Advanced Materials Laboratory, NIMS, National Institute for Materials Science, International Center for Materials Nanoarchitectonics, National Institute of Material Science, Japan, Tsukuba, National Institute for Materials Science

  • Jing Kong

    Department of Electrical Engineering, Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Massachusetts Institute of Technology MIT

  • William A. Tisdale

    Massachusetts Institute of Technology MIT

  • Nuh Gedik

    Massachusetts Institute of Technology MIT, Massachusetts Institute of Technology

  • Liang Fu

    Department of Physics, Massachusetts Institute of Technology, Massachusetts Institute of Technology MIT, Massachusetts Institute of Technology

  • Suyang Xu

    Department of Chemistry and Chemical Biology, Harvard University, Havard University, Harvard University

  • Pablo Jarillo-Herrero

    MIT, Massachusetts Institute of Technology MIT, Department of Physics, Massachusetts Institute of Technology, Massachusetts Institute of Technology, Physics, Massachusetts Institute of Technology

  • Raymond Ashoori

    Massachusetts Institute of Technology MIT, Physics, Massachusetts Institute of Technology