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arXiv · 2608.02727

Spin-charge separation in the triangular-lattice Hofstadter-Hubbard model

Yuntian Gu·Hui Yang·Zhehao Dai·Yantao Wu
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Abstract

Recent experiments in moiré materials have enabled the realization of a variety of exotic quantum phases. In this context, the Hofstadter-Hubbard model has been proposed as a possible setting for hosting chiral spin liquid. Concurrently, significant progress has been recently made in the computational methods for two-dimensional many-body fermion systems, which makes numerically studying this challenging model a real possibility in genuine 2D geometry. Motivated by these advances, we investigate the putative chiral spin liquid phase in the triangular-lattice Hofstadter-Hubbard model using variational Monte Carlo with neural quantum states (NQS) and projected entangled pair states (PEPS). We observe spin-charge separation directly in real space through numerical spin-pumping simulation and real-time spin and charge motion. In addition, in the context of anyonic superconductivity conjectured in this model, we find a positive two-electron binding energy on small systems, but it decreases below our numerical resolution as the system size increases. Our work demonstrates NQS and PEPS as powerful tools, capable of cross-checking each other, for diagnosing topological order and fractionalized excitations in strongly correlated electronic systems.

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Yuntian Gu, Hui Yang, Zhehao Dai, Yantao Wu. 2026-08-26. Spin-charge separation in the triangular-lattice Hofstadter-Hubbard model. https://arxiv.org/abs/2608.02727

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