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arXiv · 2010.12255

Hubbard model vs. Kondo model: Strong coupling limit

Ilya Ivantsov·Alvaro Ferraz·Evgenii Kochetov
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Abstract

The Hubbard model and the lattice Kondo model are shown to become identical in the strong-coupling limit. A departure from the strong-coupling regime produces distinct theories, however: the relevant perturbation terms give rise to either short-range spin exchange $(t-J$ model) or short-range charge exchange ($t-V$ model), respectively.

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Ilya Ivantsov, Alvaro Ferraz, Evgenii Kochetov. 2020-10-23. Hubbard model vs. Kondo model: Strong coupling limit. https://arxiv.org/abs/2010.12255

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