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

Invited-In-person  · 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.

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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

  • Martin Lee

  • Jiazhou Li

  • Mudit Bhatt

  • Ashwin Vadlamani

  • Moyu Chen

  • Ipsita Das

    • Princeton University

  • Janos Papp

  • Marc Currle

  • Jiabin Yu

  • Zhiyuan Zhou

  • Markus Becherer

  • Rosemarie Mittermeier

  • Philipp Altpeter

  • Christian Obermayer

  • Heribert Lorenz

  • Gabriela Chavez

  • Joshua Williams

  • Kenji Watanabe

    • National Institute for Materials Science

  • Takashi Taniguchi

    • National Institute for Materials Science

  • B. Andrei Bernevig

  • Dmitri Efetov

    • Ludwig-Maximilians-Universitaet (LMU-Munich)