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arXiv · 2004.13429

Finite-size effects in the reconstruction of dynamic properties from ab initio path integral Monte-Carlo simulations

Tobias Dornheim·Jan Vorberger
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Abstract

We systematically investigate finite-size effects in the dynamic structure factor $S(q,\omega)$ of the uniform electron gas obtained via the analytic continuation of \textit{ab initio} path integral Monte-Carlo (PIMC) data for the imaginary-time density--density correlation function $F(q,\tau)$. Using the recent scheme by Dornheim \textit{et al.}~[PRL \textbf{121}, 255001 (2018)], we find that the reconstructed spectra are not afflicted with any finite-size effects for as few as $N=14$ electrons both at warm dense matter (WDM) conditions and at the margins of the strongly correlated electron liquid regime. Our results further corroborate the high quality of our current description of the dynamic density response of correlated electrons, which is of high importance for many applications in WDM theory and beyond.

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Tobias Dornheim, Jan Vorberger. 2020-04-28. Finite-size effects in the reconstruction of dynamic properties from ab initio path integral Monte-Carlo simulations. https://doi.org/10.1103/physreve.102.063301

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