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Decoupling method for dynamical mean field theory calculations

Harald O. Jeschke·Gabriel Kotliar
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Abstract

In this paper we explore the use of an equation of motion decoupling method as an impurity solver to be used in conjunction with the dynamical mean field self-consistency condition for the solution of lattice models. We benchmark the impurity solver against exact diagonalization, and apply the method to study the infinite $U$ Hubbard model, the periodic Anderson model and the $pd$ model. This simple and numerically efficient approach yields the spectra expected for strongly correlated materials, with a quasiparticle peak and a Hubbard band. It works in a large range of parameters, and therefore can be used for the exploration of real materials using LDA+DMFT.

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Harald O. Jeschke, Gabriel Kotliar. 2004-06-21. Decoupling method for dynamical mean field theory calculations. https://doi.org/10.1103/physrevb.71.085103

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