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A note on cluster methods for strongly correlated electron systems

Giulio Biroli·Gabriel Kotliar
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Abstract

We develop, clarify and test various aspects of cluster methods dynamical mean field methods using a soluble toy model as a benchmark. We find that the Cellular Dynamical Mean Field Theory (C-DMFT) converges very rapidly and compare its convergence properties with those of the Dynamical Cluster Approximation (DCA). We propose and test improved estimators for the lattice self energy within C-DMFT.

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Giulio Biroli, Gabriel Kotliar. 2001-10-16. A note on cluster methods for strongly correlated electron systems. https://doi.org/10.1103/physrevb.65.155112

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