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arXiv · 2011.02296

Rigorous results on the ground state of the attractive SU($N$) Hubbard model

Hironobu Yoshida·Hosho Katsura
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Abstract

We study the attractive SU($N$) Hubbard model with particle-hole symmetry. The model is defined on a bipartite lattice with the number of sites $N_A$ $(N_B)$ in the $A$ $(B)$ sublattice. We prove three theorems that allow us to identify the basic ground-state properties: the degeneracy, the fermion number, and the SU($N$) quantum number. We also show that the ground state exhibits charge density wave order when $|N_A-N_B|$ is macroscopically large. The theorems hold for a bipartite lattice in any dimension, even without translation invariance.

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Hironobu Yoshida, Hosho Katsura. 2020-11-04. Rigorous results on the ground state of the attractive SU($N$) Hubbard model. https://doi.org/10.1103/physrevlett.126.100201

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