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Performance analysis of continuous-time solvers for quantum impurity models

Emanuel Gull·Philipp Werner·Andrew J. Millis·Matthias Troyer
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Abstract

Impurity solvers play an essential role in the numerical investigation of strongly correlated electrons systems within the "dynamical mean field" approximation. Recently, a new class of continuous-time solvers has been developed, based on a diagrammatic expansion of the partition function in either the interactions or the impurity-bath hybridization. We investigate the performance of these two complementary approaches and compare them to the well-established Hirsch-Fye method. The results show that the continuous-time methods, and in particular the version which expands in the hybridization, provide substantial gains in computational efficiency.

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Emanuel Gull, Philipp Werner, Andrew J. Millis, Matthias Troyer. 2007-12-28. Performance analysis of continuous-time solvers for quantum impurity models. https://doi.org/10.1103/physrevb.76.235123

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