Scanning tunneling microscopy signatures of unconventional superconductivity in twisted trilayer graphene

ORAL  · Invited

Abstract

Magic-angle twisted trilayer graphene stands out as a highly tunable material that exhibits strong electronic correlations and robust unconventional superconductivity. However, understanding the interplay between the low-temperature superconducting phase and the other correlated phases that form at higher temperatures remains elusive. In this talk, we will review signatures of unconventional superconductivity as observed by scanning tunneling microscopy and spectroscopy. In particular, we will focus on a doping range where two spectroscopic gaps centered around the Fermi level can be identified. In this range, further measurements in a finite magnetic field, elevated temperatures, and in the contact regime enable us to discern the origin of the two gaps. Finally, we will show how the spatial variation of the gaps on the atomic scale provides further insights into the nature of superconductivity and its rich intertwinement with other correlated phases in the system.

*Acknowledgment: This work has been primarily supported by the Office of Naval Research (grant no. N142112635) and in part by the Institute for Quantum Information and Matter, a National Science Foundation Physics Frontiers Center (PHY-2317110), and the Gordon and Betty Moore Foundation (grant DOI: 10.37807/GBMF12967). We gratefully acknowledge the critical support and infrastructure provided for this work by the Kavli Nanoscience Institute at Caltech.

Publication: [1] Hyunjin Kim, Gautam Rai, Lorenzo Crippa, Dumitru Călugăru, Haoyu Hu, Youngjoon Choi, Lingyuan Kong, Eli Baum, Yiran Zhang, Ludwig Holleis, Kenji Watanabe, Takashi Taniguchi, Andrea F Young, B Andrei Bernevig, Roser Valentí, Giorgio Sangiovanni, Tim Wehling, Stevan Nadj-Perge, ArXiv preprint arXiv:2505.17200 (2025).
[2] Hyunjin Kim, Youngjoon Choi, Étienne Lantagne-Hurtubise, Cyprian Lewandowski, Alex Thomson, Lingyuan Kong, Haoxin Zhou, Eli Baum, Yiran Zhang, Ludwig Holleis, Kenji Watanabe, Takashi Taniguchi, Andrea F. Young, Jason Alicea, Stevan Nadj-Perge, Nature 623, 942–948 (2023).
[3] Hyunjin Kim, Youngjoon Choi, Cyprian Lewandowski, Alex Thomson, Yiran Zhang, Robert Polski, Kenji Watanabe, Takashi Taniguchi, Jason Alicea, Stevan Nadj-Perge, Nature 606, 494–500 (2022).
[4] Hyunjin Kim, et al. (in preparation) (2026).

Presenters

  • Stevan Nadj-Perge

    • Caltech

Authors

  • Stevan Nadj-Perge

    • Caltech