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Exact Results of Strongly Correlated Systems at Finite Temperature

Sze-Shiang Feng
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Abstract

Some rigorous conclusions of the Hubbard model, Kondo lattice model and periodic Anderson model at finite temperature are acquired employing the fluctuation-dissipation theorem and particle-hole transform. The main conclusion states that for the three models, the expectation value of ${\bf \tilde{S}}^2-{\bf \tilde{S}}^2_z$ will be of order $N_Λ$ at any finite temperature.

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Sze-Shiang Feng. 1999-04-17. Exact Results of Strongly Correlated Systems at Finite Temperature. https://doi.org/10.1016/s0375-9601(99)00169-3

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