Revealing electron-electron interactions in graphene at room temperature with the quantum twisting microscope

ORAL  · Invited

Abstract

The Quantum Twisting Microscope (QTM)1-3 is a revolutionary instrument that enables energy- and momentum-resolved measurements of quantum phases through tunneling spectroscopy across twistable van der Waals heterostructures. In our experimental work, we substantially improve the QTM's resolution and extend its measurement range to higher energies and twist angles by incorporating hexagonal boron nitride (hBN) as a tunneling dielectric. This enhancement reveals previously inaccessible features of the tunneling dispersion between two monolayer graphene sheets, such as an unprecedented splitting of the branches arising from the nesting condition. 

A theoretical analysis shows that the linear dispersion in graphene obtains a logarithmic correction through strong electron-electron interactions4-18, which is experimentally resolvable in the QTM even at room temperature, where such corrections are typically weak. The high sensitivity of the QTM thus makes it a powerful tool to observe even small modifications of the band structure. We extend our experimental investigation to spectra resulting from tunneling between monolayer and various multilayer graphene devices, including Bernal-stacked multilayer and rhombohedral trilayer systems.

*D.K.E. acknowledges funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement No. 852927), the German Research Foundation (DFG) under the priority program SPP2244 (project No. 535146365), the EU EIC Pathfinder Grant "FLATS" (grant agreement No. 101099139) and the Tschira foundation under the project SuperC. B.A.B. was supported by the Gordon and Betty Moore Foundation through Grant No. GBMF8685 and the EPiQS Initiative (Grant No. GBMF11070), the Office of Naval Research (ONR Grant No. N00014-20-1-2303), the Global Collaborative Network Grant at Princeton University, the Simons Investigator Grant No. 404513, the BSF Israel US foundation No. 2018226, the NSF-MERSEC (Grant No. MERSEC DMR 2011750), the Simons Collaboration on New Frontiers in Superconductivity (SFI-MPS-NFS00006741-01), and the Schmidt Foundation.

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Presenters

  • Maximilian Daschner

    • Ludwig Maximilian University of Munich

Authors

  • Maximilian Daschner

    • Ludwig Maximilian University of Munich

  • Jonah Herzog-Arbeitman

    • Princeton University
    • Department of Physics, Princeton University

  • Martin Lee

    • TU Eindhoven

  • Jiazhou Li

    • Ludwig Maximilian University of Munich

  • Mudit Bhatt

    • Ludwig Maximilian University of Munich

  • Ashwin Vadlamani

    • Ludwig Maximilian University of Munich

  • Moyu Chen

    • Ludwig Maximilian University of Munich

  • Ipsita Das

    • Princeton University

  • Janos Papp

    • Ludwig Maximilian University of Munich

  • Marc Currle

    • Ludwig Maximilian University of Munich

  • Jiabin Yu

    • Princeton University

  • Zhiyuan Zhou

    • Peking University

  • Markus Becherer

    • Technical University of Munich

  • Rosemarie Mittermeier

    • Technical University of Munich

  • Philipp Altpeter

    • Ludwig Maximilian University of Munich

  • Christian Obermayer

    • Ludwig Maximilian University of Munich

  • Heribert Lorenz

    • Ludwig Maximilian University of Munich

  • Gabriela Chavez

    • Ludwig Maximilian University of Munich

  • Joshua Williams

    • Ludwig Maximilian University of Munich

  • Kenji Watanabe

    • National Institute for Materials Science
    • Research Center for Functional Materials, National Institute of Materials Science, 1-1 Namiki Tsukuba, Ibaraki 305-0044, Japan

  • Takashi Taniguchi

    • National Institute for Materials Science
    • Research Center for Materials Nanoarchitectonics, National Institute for Materials Science
    • International Center for Materials Nanoarchitectonics, National Institute of Materials Science, 1-1 Namiki Tsukuba, Ibaraki 305-0044, Japan
    • Research Center for Functional Materials, National Institute of Materials Science, 1-1 Namiki Tsukuba, Ibaraki 305-0044, Japan

  • Andrei B Bernevig

    • Princeton University
    • Department of Physics, Princeton University

  • Dmitri K. Efetov

    • Ludwig-Maximilians-Universitaet (LMU-Munich)