An Analytical Strong Coupling Approach in Dynamical Mean-field Theory
نویسنده
چکیده
Institute for Condensed Matter Physics, Natl. Acad. Sci. Ukr. 1 Svientsitskii Str., UA-79011 Lviv, Ukraine (Received June 21, 2001) In the limit of infinite spatial dimensions a thermodynamically consistent theory of the strongly correlated electron systems, which is valid for arbitrary value of the Coulombic interaction (U < ∞), is built. For the Hubbard model the total auxiliary single-site problem exactly splits into four subspaces, which describe Fermi and non-Fermi liquid components. Such analytical approach allows to construct different thermodynamically consistent approximations: alloy-analogy approximation, Hartree-Fock approximation and further, that describes the self-consistent renormalization of the bosonic excitations (magnons and doublons). PACS numbers: 71.10.Fd, 71.15.Mb, 05.30.Fk, 71.27.+a
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