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arXiv · 2307.09500

Exact hole-induced $SU(N)$ flavor-singlets in certain $U=\infty$ $SU(N)$ Hubbard models

Kyung-Su Kim·Hosho Katsura
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Abstract

We prove that the motion of a single hole induces $SU(N)$ flavor-singlets in the $U=\infty$ $SU(N)$ (Fermi) Hubbard model on a Husimi-like tree graph. The result is also generalized to certain $t$-$J$ models with antiferromagnetic interactions and singlet hopping terms typically neglected in the literature. This is an $SU(N)$ generalization of the "counter-Nagaoka theorem" introduced in [Phys. Rev. B 107, L140401 (2023)]. Our results suggest the existence of antiferromagnetic or resonating-valence-bond (RVB)-like polarons in the $t$-$J$ models on a more realistic non-bipartite lattice. Such antiferromagnetic/RVB polarons may be relevant for a novel strong-coupling mechanism of superconductivity or other exotic fractionalized phases of matter.

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Kyung-Su Kim, Hosho Katsura. 2023-07-18. Exact hole-induced $SU(N)$ flavor-singlets in certain $U=\infty$ $SU(N)$ Hubbard models. https://doi.org/10.1103/physrevresearch.6.013307

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