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Equation-of-Motion Approach to Dynamical Mean Field Theory

Jian-Xin Zhu·R. C. Albers·J. M. Wills
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Abstract

We propose using an equation-of-motion approach as an impurity solver for dynamical mean field theory. As an illustration of this technique, we consider a finite-$U$ Hubbard model defined on the Bethe lattice with infinite connectivity at arbitrary filling. Depending on the filling, the spectra that is obtained exhibits a quasiparticle peak, and lower and upper Hubbard bands as typical features of strongly correlated materials. The results are also compared and in good agreement with exact diagonalization. We also find a different picture of the spectral weight transfer than the iterative perturbation theory.

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Jian-Xin Zhu, R. C. Albers, J. M. Wills. 2004-09-08. Equation-of-Motion Approach to Dynamical Mean Field Theory. https://arxiv.org/abs/cond-mat/0409215

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