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arXiv · 1107.5536

High-frequency asymptotic behavior of self-energies in quantum impurity models

Xin Wang·Hung The Dang·Andrew J. Millis
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Abstract

We present explicit expressions for the high-frequency asymptotic behavior of electron self-energy of general quantum impurity models, which may be useful for improving the convergence of dynamical mean-field calculations and for the analytic continuation of the electron self-energy. We also give results, expressed in more physical terms, for the two-orbital and three-orbital rotationally invariant Slater-Kanamori interactions, in order to facilitate calculations of transition metal oxides.

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Xin Wang, Hung The Dang, Andrew J. Millis. 2011-07-27. High-frequency asymptotic behavior of self-energies in quantum impurity models. https://doi.org/10.1103/physrevb.84.073104

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