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arXiv · 2605.06923

Topological superconductivity in a Hubbard model for twisted bilayer cuprates

T. Vibert·D. Sénéchal
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Abstract

We investigate the emergence of nontrivial topology in a twisted cuprate bilayer described by the Hubbard model in the weak-interaction regime. Our results show that the topological character depends sensitively on the doping level. For $U/t=3.85$, the Chern number assumes a value of $\pm 8$ in the electron-doped case, whereas it vanishes (0) in the hole-doped regime. The presence of nontrivial topology is further supported by an analysis the associated edge states and their chirality in a finite-width geometry, while keeping full correlations.

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T. Vibert, D. Sénéchal. 2026-08-15. Topological superconductivity in a Hubbard model for twisted bilayer cuprates. https://doi.org/10.1103/hdxf-sqwn

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