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Dynamical Charge Susceptibility of the Spinless Falicov-Kimball Model

J. K. Freericks·P. Miller
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Abstract

An exact solution is presented for the frequency-dependent charge susceptibility of the spinless Falicov-Kimball model by using dynamical mean-field theory. We develop a nontrivial application of the Baym-Kadanoff "conserving approximation" formalism to exactly determine the frequency-dependent vertex function (which turns out to assume a particularly simple form). We show how the static and dynamic susceptibilities are decoupled in this model and how the dynamic susceptibility generically does not show any signal of the low-temperature charge-density-wave phase transition. We also examine the temperature evolution of the dynamic charge susceptibility for the special case of half-filling.

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J. K. Freericks, P. Miller. 2000-05-04. Dynamical Charge Susceptibility of the Spinless Falicov-Kimball Model. https://doi.org/10.1103/physrevb.62.10022

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