Pairing from repulsive interactions in twisted WSe2 from functional renormalization

Hannes Braun; Dumitru Călugăru; Pietro M. Bonetti; Haoyu Hu; Yan Zhang; Yi Jiang; Quansheng Wu; Kin Fai Mak; Jie Shan; B. Andrei Bernevig; Michael M. Scherer; Laura Classen

arXiv · 2610.17222

Pairing from repulsive interactions in twisted WSe2 from functional renormalization

Hannes Braun·Dumitru Călugăru·Pietro M. Bonetti·Haoyu Hu·Yan Zhang·Yi Jiang·Quansheng Wu·Kin Fai Mak·Jie Shan·B. Andrei Bernevig·Michael M. Scherer·Laura Classen

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Abstract

Motivated by the observation of superconductivity in twisted bilayer WSe$_2$ over an extended range of displacement fields, reaching from the correlated insulator down to zero field, we analyze the correlated electron phases of this system at hole filling $ν= -1$ and twist angle $3.65^\circ$ using Hartree--Fock, random phase approximation, and functional renormalization group calculations. We derive a continuum model with gate-screened Coulomb interaction from first principles and compare its instabilities to those of a realistic three-orbital Wannier model with a Hubbard interaction and an artificial single-orbital Hubbard model. In both cases, we find a superconducting instability of mixed $d$-wave singlet and $p$-wave triplet character, arising adjacent to inter-valley-coherent spin-density-wave order in the phase diagram spanned by displacement field and interaction strength. Our additional analysis of the pairing mechanism points to inter-valley coherent spin fluctuations as the pairing glue. The extent of the pairing regime and the associated critical temperatures depend on the model input, and we trace differences to the interaction range entering the projected interaction. Within the continuum model, the gate-screened Coulomb interaction yields pairing down to zero displacement field, bringing theory into agreement with experiment.

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Hannes Braun, Dumitru Călugăru, Pietro M. Bonetti, Haoyu Hu, Yan Zhang, Yi Jiang, Quansheng Wu, Kin Fai Mak, Jie Shan, B. Andrei Bernevig, Michael M. Scherer, Laura Classen. 2026-10-12. Pairing from repulsive interactions in twisted WSe2 from functional renormalization. https://arxiv.org/abs/2610.17222

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