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Symmetry Properties on Magnetization in the Hubbard Model at Finite Temperatures

Gang Su·Masuo Suzuki
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Abstract

By making use of some symmetry properties of the relevant Hamiltonian, two fundamental relations between the ferromagnetic magnetization and a spin correlation function are derived for the $d (=1,2,3)$-dimensional Hubbard model at finite temperatures. These can be viewed as a kind of Ward-Takahashi identities. The properties of the magnetization as a function of the applied field are discussed. The results thus obtained hold true for both repulsive and attractive on-site Coulomb interactions, and for arbitrary electron fillings.

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Gang Su, Masuo Suzuki. 1998-03-10. Symmetry Properties on Magnetization in the Hubbard Model at Finite Temperatures. https://doi.org/10.1103/physrevb.57.13367

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