Physical review. B, Condensed matter
Dynamical charge response function of the Hubbard model in the slave-boson approach
T. Li
Abstract
A concise general expression for the dynamical charge susceptibility of the Hubbard model is presented. The results are obtained from the spin-rotation-invariant slave-boson theory, whose paramagnetic saddle point corresponds to Gutzwiller's variational approximation. The charge structure factor and charge susceptibility are calculated for a wide range of interactions and temperatures and are compared thoroughly with the available quantum Monte Carlo and variational Monte Carlo results for the one-dimensional Hubbard model. The comparison shows reasonable agreement. All the calculations are done in a totally self-consistent way, without adjustable parameters.