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arXiv · 2509.07799

An integrable Anderson-impurity problem embedded in the one-dimensional Hubbard model

Renjie Song·Mingchen Zheng·Junpeng Cao·Yupeng Wang
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Abstract

An exactly solvable one-dimensional Hubbard model with a single Anderson impurity embedded at the boundary is constructed in the framework of the quantum inverse scattering method. The model is solved exactly by the nested Bethe ansatz method. We identify the boundary bound states and determine the ground state phase diagram. By deriving the impurity contribution to the magnetic susceptibility, we show that in the dilute electron limit, a nearly free local moment forms at the impurity site, while at finite electron densities, the impurity spin is screened by the host electrons, consistent with Kondo physics.

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Renjie Song, Mingchen Zheng, Junpeng Cao, Yupeng Wang. 2025-09-09. An integrable Anderson-impurity problem embedded in the one-dimensional Hubbard model. https://arxiv.org/abs/2509.07799

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