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arXiv · 2506.18886

Finite-momentum superconductivity from chiral bands in twisted MoTe$_2$

Yinqi Chen·Cheng Xu·Yang Zhang·Constantin Schrade
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Abstract

A recent experiment has reported unconventional superconductivity in twisted bilayer MoTe$_2$, emerging from a normal state that exhibits a finite anomalous Hall effect -- a signature of intrinsic chirality. Motivated by this discovery, we construct a continuum model for twisted MoTe$_2$ constrained by lattice symmetries from first-principles calculations that captures the moiré-induced inversion symmetry breaking even in the absence of a displacement field. Building on this model, we show that repulsive interactions give rise to finite-momentum superconductivity via the Kohn-Luttinger mechanism in this chiral moiré system. Remarkably, the finite-momentum superconducting state can arise solely from internal symmetry breaking of the moiré superlattice, differentiating it from previously studied cases that require external fields. It further features a nonreciprocal quasiparticle dispersion and an intrinsic superconducting diode effect. Our results highlight a novel route to unconventional superconducting states in twisted transition metal dichalcogenides moiré systems, driven entirely by intrinsic symmetry-breaking effects.

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Yinqi Chen, Cheng Xu, Yang Zhang, Constantin Schrade. 2025-06-23. Finite-momentum superconductivity from chiral bands in twisted MoTe$_2$. https://doi.org/10.1038/s41467-025-67836-9

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