Improved Green's Function Measurement for Hybridization Expansion Quantum Monte Carlo

Pavel Augustinský; Jan Kuneš

doi:10.1016/j.cpc.2013.04.005

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arXiv · 1302.4594

Improved Green's Function Measurement for Hybridization Expansion Quantum Monte Carlo

Pavel Augustinský·Jan Kuneš

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Abstract

We present an algorithm for measurement of the Green's function in the hybridization expansion continuous-time quantum Monte-Carlo based on continuous estimators. Compared to the standard method, the present algorithm has similar or better accuracy with improvement notable especially at low perturbation orders and high frequencies. The resulting statistical noise is weakly correlated so high-accuracy data for the numerical analytical continuation can be produced.

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Pavel Augustinský, Jan Kuneš. 2013-02-19. Improved Green's Function Measurement for Hybridization Expansion Quantum Monte Carlo. https://doi.org/10.1016/j.cpc.2013.04.005

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