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arXiv · 2002.12372

Quantum Quasi-Monte Carlo Technique for Many-Body Perturbative Expansions

Marjan Maček·Philipp T. Dumitrescu·Corentin Bertrand·Bill Triggs·Olivier Parcollet·Xavier Waintal
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Abstract

High order perturbation theory has seen an unexpected recent revival for controlled calculations of quantum many-body systems, even at strong coupling. We adapt integration methods using low-discrepancy sequences to this problem. They greatly outperform state-of-the-art diagrammatic Monte Carlo. In practical applications, we show speed-ups of several orders of magnitude with scaling as fast as $1/N$ in sample number $N$; parametrically faster than $1/\sqrt{N}$ in Monte Carlo. We illustrate our technique with a solution of the Kondo ridge in quantum dots, where it allows large parameter sweeps.

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Marjan Maček, Philipp T. Dumitrescu, Corentin Bertrand, Bill Triggs, Olivier Parcollet, Xavier Waintal. 2020-02-27. Quantum Quasi-Monte Carlo Technique for Many-Body Perturbative Expansions. https://doi.org/10.1103/physrevlett.125.047702

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