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arXiv · 0804.1376

Construction of density operator for a general mean-field Hamiltonian and its application to the models of correlated fermions

Jakub Jȩdrak·Jozef Spałek
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Abstract

We analyze a class of mean-field (MF) lattice-fermion Hamiltonians and construct the corresponding grand-canonical density operator for such system. New terms are introduced, which may be interpreted as local fugacities, molecular fields, etc. The presence of such terms is an unavoidable consequence of a consistent statistical description. Although in some cases (e.g. in the Hartree or the Hartree-Fock-type approximation) the presented formalism is redundant, in general (e.g. for a renormalized t-J model) it leads to nontrivial modifications of the thermodynamic properties.

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Jakub Jȩdrak, Jozef Spałek. 2009-09-01. Construction of density operator for a general mean-field Hamiltonian and its application to the models of correlated fermions. https://arxiv.org/abs/0804.1376

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