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arXiv · 2305.04310

Slave spin theory of magnetic states in Hubbard model

Jiasheng Qian·Zhiguang Liao·Rong Yu
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Abstract

Magnetic properties of Hubbard model have been studied extensively. A theoretical description of these states, however, is not straight forward within conventional mean-field approach due to the electron correlation effects. Here we provide a slave spin theory of the magnetic states in the single band Hubbard model. By introducing an additional decomposition of the on-site Coulomb interaction in the magnetic channel in both the slave spin and the fermionic spinon sectors, we show a magnetic solution with renormalized quasiparticle spectral weight can be stabilized at both half-filling and finite doping. By comparing the energies of antiferromagnetic and ferromagnetic states, we provide a ground-state phase diagram for generic electron filling. We further discuss possible generalization of the slave-spin method.

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Jiasheng Qian, Zhiguang Liao, Rong Yu. 2023-05-07. Slave spin theory of magnetic states in Hubbard model. https://arxiv.org/abs/2305.04310

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