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arXiv · 0907.0863

Diagrammatic Monte Carlo for Correlated Fermions

E. Kozik·K. Van Houcke·E. Gull·L. Pollet·N. Prokof'ev·B. Svistunov·M. Troyer
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Abstract

We show that Monte Carlo sampling of the Feynman diagrammatic series (DiagMC) can be used for tackling hard fermionic quantum many-body problems in the thermodynamic limit by presenting accurate results for the repulsive Hubbard model in the correlated Fermi liquid regime. Sampling Feynman's diagrammatic series for the single-particle self-energy we can study moderate values of the on-site repulsion ($U/t \sim 4$) and temperatures down to $T/t=1/40$. We compare our results with high temperature series expansion and with single-site and cluster dynamical mean-field theory.

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E. Kozik, K. Van Houcke, E. Gull, L. Pollet, N. Prokof'ev, B. Svistunov, M. Troyer. 2010-01-22. Diagrammatic Monte Carlo for Correlated Fermions. https://doi.org/10.1209/0295-5075%2F90%2F10004

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