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arXiv · 1702.03054

Compressing Green's function using intermediate representation between imaginary-time and real-frequency domains

Hiroshi Shinaoka·Junya Otsuki·Masayuki Ohzeki·Kazuyoshi Yoshimi
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Abstract

New model-independent compact representations of imaginary-time data are presented in terms of the intermediate representation (IR) of analytical continuation. This is motivated by a recent numerical finding by the authors [J. Otsuki et al., arXiv:1702.03056]. We demonstrate the efficiency of the IR through continuous-time quantum Monte Carlo calculations of an Anderson impurity model. We find that the IR yields a significantly compact form of various types of correlation functions. The present framework will provide general ways to boost the power of cutting-edge diagrammatic/quantum Monte Carlo treatments of many-body systems.

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Hiroshi Shinaoka, Junya Otsuki, Masayuki Ohzeki, Kazuyoshi Yoshimi. 2017-02-10. Compressing Green's function using intermediate representation between imaginary-time and real-frequency domains. https://doi.org/10.1103/physrevb.96.035147

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