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arXiv · 2608.14503

Chiral spin liquid and chiral antiferromagnetism in half-filled moiré Hubbard model: possible applications to twisted bilayer TMDs

Chuyi Tuo·Hong Yao
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Abstract

Twisted transition metal dichalcogenides offer an exceptionally tunable moiré platform for studying correlation physics beyond conventional condensed matter systems. In particular, the intriguing interplay between the displacement field and the twist angle remains to be fully resolved. In this paper, we use large-scale density matrix renormalization group simulations to study the minimal moiré Hubbard model on a triangular lattice at half-filling, where the displacement field effect is captured by a spin-dependent staggered flux. We find that the displacement field significantly enriches the triangular Hubbard phase diagram in several qualitative ways. It rapidly destabilizes the chiral spin liquid phase beyond a narrow weak-field regime, induces pronounced chiral correlations in the strong-coupling $120^\circ$-antiferromagnetic phase, and stabilizes incommensurate spin-density wave phases at weaker coupling. We further find signatures of a continuous transition between the chiral spin liquid and chiral antiferromagnetic phases at a finite displacement field, potentially driven by spinon condensation. Our results uncover rich displacement-field-driven many-body physics and provide useful guidance for future experiments in moiré superlattice systems.

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Chuyi Tuo, Hong Yao. 2026-08-14. Chiral spin liquid and chiral antiferromagnetism in half-filled moiré Hubbard model: possible applications to twisted bilayer TMDs. https://arxiv.org/abs/2608.14503

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