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Variational cluster approach to correlated electron systems in low dimensions

M. Potthoff·M. Aichhorn·C. Dahnken
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Abstract

A self-energy-functional approach is applied to construct cluster approximations for correlated lattice models. It turns out that the cluster-perturbation theory (Senechal et al, PRL 84, 522 (2000)) and the cellular dynamical mean-field theory (Kotliar et al, PRL 87, 186401 (2001)) are limiting cases of a more general cluster method. Results for the one-dimensional Hubbard model are discussed with regard to boundary conditions, bath degrees of freedom and cluster size.

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M. Potthoff, M. Aichhorn, C. Dahnken. 2003-11-20. Variational cluster approach to correlated electron systems in low dimensions. https://doi.org/10.1103/physrevlett.91.206402

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