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arXiv · 2207.09498

Exact Hole-induced Resonating-Valence-Bond Ground State in Certain $U=\infty$ Hubbard Models

Kyung-Su Kim
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Abstract

We prove that the motion of a single hole induces the nearest-neighbor resonating-valence-bond ground state in the $U=\infty$ Hubbard model on a triangular cactus - a tree-like variant of a kagome lattice. The result can be easily generalized to $t-J$ models with antiferromagnetic interactions $J\geq 0$ on the same graphs. This is a weak converse of Nagaoka's theorem of ferromagnetism on a bipartite lattice.

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Kyung-Su Kim. 2022-07-19. Exact Hole-induced Resonating-Valence-Bond Ground State in Certain $U=\infty$ Hubbard Models. https://doi.org/10.1103/physrevb.107.l140401

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