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arXiv · 0903.4838

A fast impurity solver based on equations of motion and decoupling

Qingguo Feng·Yuzhong Zhang·Harald O. Jeschke
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Abstract

In this paper a fast impurity solver is proposed for dynamical mean field theory (DMFT) based on a decoupling of the equations of motion for the impurity Greens function. The resulting integral equations are solved efficiently with a method based on genetic algorithms. The Hubbard and periodic Anderson models are studied with this impurity solver. The method describes the Mott metal insulator transition and works for a large range of parameters at finite temperature on the real frequency axis. This makes it useful for the exploration of real materials in the framework of LDA+DMFT.

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Qingguo Feng, Yuzhong Zhang, Harald O. Jeschke. 2009-05-19. A fast impurity solver based on equations of motion and decoupling. https://doi.org/10.1103/physrevb.79.235112

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