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arXiv · 1712.10001

Determinant Monte Carlo for irreducible Feynman diagrams in the strongly correlated regime

Fedor Simkovic IV.·Evgeny Kozik
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Abstract

We develop a numerically exact method for the summation of irreducible Feynman diagrams for fermionic self-energy in the thermodynamic limit. The technique, based on the Diagrammatic Determinant Monte Carlo and its recent extension to connected diagrams, allows us to reach high ($\sim 10$) orders of the weak-coupling expansion for the self-energy of the two-dimensional Hubbard model. Access to high orders reveals a non-trivial analytic structure of the self-energy and enables its controlled reconstruction with arbitrary momentum resolution in the nonperturbative regime of essentially strong correlations, which has recently been reached with ultracold atoms in optical lattices.

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Fedor Simkovic IV., Evgeny Kozik. 2019-09-04. Determinant Monte Carlo for irreducible Feynman diagrams in the strongly correlated regime. https://doi.org/10.1103/physrevb.100.121102

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