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On the Analyticity of Solutions in the Dynamical Mean-Field Theory

Th. Pruschke·W. Metzner·D. Vollhardt
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Abstract

The unphysical solutions of the periodic Anderson model obtained by H. Keiter and T. Leuders [Europhys. Lett. 49, 801(2000)] in dynamical mean-field theory (DMFT) are shown to result from the author's restricted choice of the functional form of the solution, leading to a violation of the analytic properties of the exact solution. By contrast, iterative solutions of the self-consistency condition within the DMFT obtained by techniques which preserve the correct analytic properties of the exact solution (e.g., quantum Monte-Carlo simulations or the numerical renormalization group) always lead to physical solutions.

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Th. Pruschke, W. Metzner, D. Vollhardt. 2001-09-05. On the Analyticity of Solutions in the Dynamical Mean-Field Theory. https://doi.org/10.1088/0953-8984%2F13%2F42%2F306

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