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arXiv · 2507.09586

Pseudogap in the lightly hole-doped triangular-lattice moir\'e Hubbard model

V. I. Kuz'min·M. A. Visotin·S. G. Ovchinnikov
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Abstract

The electronic structure of the lightly hole-doped triangular-lattice moir\'e Hubbard model is studied within cluster perturbation theory (CPT) using 13-site clusters for a fixed doping concentration $p=1/13$ varying the Coulomb parameter $U$ and the hopping phase parameter $\phi$ related to the spin-orbital interaction. We have also developed a rather simple generalized mean-field approximation (GMFA) containing the amplitude of the spin correlations as a free parameter to fit the CPT data.The evolution of the Fermi surface and the pseudogap with the parameters $\phi$ and $U$ is explained from the viewpoint of the short-range magnetic order. The geometric frustration and the additional model parameter related to the spin-orbital interaction result in a more rich physics of the pseudogap state compared to the case of a more conventional square lattice.

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V. I. Kuz'min, M. A. Visotin, S. G. Ovchinnikov. 2025-07-13. Pseudogap in the lightly hole-doped triangular-lattice moir\'e Hubbard model. https://doi.org/10.1103/22j6-2p89

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