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arXiv · 2509.22902

Tunneling spectroscopy of two-dimensional superconductors with the quantum twisting microscope

Nemin Wei·Felix von Oppen·Leonid I. Glazman
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Abstract

The ongoing discoveries of graphene-based superconductors underscore the quest to understand the structure of new superconducting orders. We develop a theory that facilitates the use of the quantum twisting microscope (QTM) for that purpose. This work investigates momentum-conserving tunneling across a planar junction formed by a normal monolayer graphene tip and a superconducting graphene sample within the QTM setting. We show that the bias dependence of the zero-temperature tunneling conductance exhibits singularities that provide momentum-resolved information about the Bogoliubov quasiparticle spectra, including the superconducting gap. Using a model of superconducting twisted bilayer graphene (TBG), we illustrate that simultaneously tuning the tip doping level and the tip-sample twist angle allows for measuring the momentum-resolved superconducting gap in TBG. Our results indicate that momentum-conserving tunneling spectroscopy with the QTM is a promising method for exploring superconductivity in two-dimensional van der Waals materials.

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Nemin Wei, Felix von Oppen, Leonid I. Glazman. 2025-09-26. Tunneling spectroscopy of two-dimensional superconductors with the quantum twisting microscope. https://arxiv.org/abs/2509.22902

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