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Improved Treatment of Frequency Sums in Propagator-Renormalized Perturbation Theories

J. J. Deisz·D. W. Hess·J. W. Serene
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Abstract

We present a massively parallel algorithm for calculating the self-energy in self-consistent finite temperature perturbation theory for lattice models. The algorithm uses analytic functions with appropriate asymptotic high frequency behavior and fast Fourier transforms to accurately calculate the self-energy at low-frequency. Traditional methods that truncate the high frequency tails of the temperature Green's function lead to `contamination' of the low-frequency behavior of the self-energy. Our algorithm is both accurate and scalable. We compare results for the Hubbard model using various techniques for handling the high frequency tails of the temperature Green's function.

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J. J. Deisz, D. W. Hess, J. W. Serene. 1994-11-04. Improved Treatment of Frequency Sums in Propagator-Renormalized Perturbation Theories. https://arxiv.org/abs/cond-mat/9411026

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