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arXiv · 2509.19436

Interplay between many-body correlations, strain and lattice relaxation in twisted bilayer graphene

Lorenzo Crippa·Gautam Rai·Dumitru Călugăru·Haoyu Hu·Jonah Herzog-Arbeitman·B. Andrei Bernevig·Roser Valentí·Giorgio Sangiovanni·Tim Wehling
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Abstract

In twisted bilayer graphene, a unified understanding of the mechanisms governing temperature-dependent electronic spectra and thermodynamic properties remains controversial despite extensive theoretical efforts. Here, we present a comprehensive theoretical framework that quantitatively accounts for scanning tunneling spectroscopy, quantum twisting microscopy, and thermodynamic properties of magic angle twisted bilayer graphene. We demonstrate that the observed behavior arises from the interplay between electron correlations and external symmetry-breaking induced by strain and lattice relaxation. These effects act cooperatively to shape the emergent electronic behavior, leaving characteristic signatures across spectroscopy, compressibility and entropy.

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Lorenzo Crippa, Gautam Rai, Dumitru Călugăru, Haoyu Hu, Jonah Herzog-Arbeitman, B. Andrei Bernevig, Roser Valentí, Giorgio Sangiovanni, Tim Wehling. 2025-09-23. Interplay between many-body correlations, strain and lattice relaxation in twisted bilayer graphene. https://doi.org/10.1103/x2mz-hm8y

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