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Analytical Results for the Grand-Canonical Partition Function for Unidimensional Hubbard Model up to Order $β^5$

I. C. Charret·E. V. Correa Silva·S. M. de Souza·M. T. Thomaz
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Abstract

We calculate the exact analytical coefficients of the $β$ expansion of the grand-canonical partition function of the unidimensional Hubbard model up to order $β^5$, using an alternative method, based on properties of the Grassmann algebra. The results derived are non-perturbative and no restrictions on the set of parameters that characterize the model are required. By applying this method we obtain analytical results for the thermodynamical quantities, in the high-temeprature limit, for arbitrary density of electrons in the unidimensional chain.

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I. C. Charret, E. V. Correa Silva, S. M. de Souza, M. T. Thomaz. 1997-05-23. Analytical Results for the Grand-Canonical Partition Function for Unidimensional Hubbard Model up to Order $β^5$. https://arxiv.org/abs/cond-mat/9705241

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