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arXiv · 1808.05188

Algorithmic Matsubara Integration for Hubbard-like models

Amir Taheridehkordi·S. H. Curnoe·J. P. F. LeBlanc
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Abstract

We present an algorithm to evaluate Matsubara sums for Feynman diagrams comprised of bare Green's functions with single-band dispersions with local U Hubbard interaction vertices. The algorithm provides an exact construction of the analytic result for the frequency integrals of a diagram that can then be evaluated for all parameters $U$, temperature $T$, chemical potential $μ$, external frequencies and internal/external momenta. This method allows for symbolic analytic continuation of results to the real frequency axis, avoiding any ill-posed numerical procedure. When combined with diagrammatic Monte-Carlo, this method can be used to simultaneously evaluate diagrams throughout the entire $T-U-μ$ phase space of Hubbard-like models at minimal computational expense.

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Amir Taheridehkordi, S. H. Curnoe, J. P. F. LeBlanc. 2018-08-15. Algorithmic Matsubara Integration for Hubbard-like models. https://doi.org/10.1103/physrevb.99.035120

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