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Correlated hopping in the Falicov-Kimball model: A large-dimensions study

Avraham Schiller
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Abstract

The Falicov-Kimball model with a correlated-hopping interaction is solved using an extended dynamical mean-field theory that becomes exact in the limit of large dimensions. The effect of correlated hopping is to introduce nonlocal self-energy components that retain full dynamics as D goes to infinity, thus introducing an explicit k-dependence to the single-particle self-energy. An explicit solution for the homogeneous phase at D = 2 reveals significant nonlocal dynamical contributions in the physically relevant regime of a moderately large correlated-hopping amplitude, indicating that important nonlocal correlations are omitted in Hubbard-like models upon neglecting the correlated-hopping interaction.

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Avraham Schiller. 1999-11-09. Correlated hopping in the Falicov-Kimball model: A large-dimensions study. https://doi.org/10.1103/physrevb.60.15660

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