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arXiv · 2502.10023

Phases and criticality of the triangular lattice SU(N) Hofstadter-Hubbard model

Lu Zhang·Rongning Liu·Xue-Yang Song
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Abstract

We report the study of phases and transitions of SU(N) Hofstadter-Hubbard model subject to commensurate magnetic field on the triangular lattice. At filling one fermion per site, for the number of fermion flavors 2 <= N <= 8, we identify three distinct phases and calculate critical interaction strength from parton large-N mean-field approximation. Integer quantum Hall, chiral spin liquid, and valence bond solid states could be realized upon varying the Hubbard interaction U and the number of flavor N . We construct the critical theory for the putative continuous transition from quantum Hall states to chiral spin liquid and calculate the critical transport behavior using quantum Boltzmann equations for general N . These results could be validated in synthetic systems such as moire superlattices and cold atom platforms.

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Lu Zhang, Rongning Liu, Xue-Yang Song. 2025-02-14. Phases and criticality of the triangular lattice SU(N) Hofstadter-Hubbard model. https://doi.org/10.1103/j9mv-75ls

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