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arXiv · 2403.01979

Ab initio path integral Monte Carlo simulations of warm dense two-component systems without fixed nodes: structural properties

Tobias Dornheim·Sebastian Schwalbe·Maximilian Böhme·Zhandos Moldabekov·Jan Vorberger·Panagiotis Tolias
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Abstract

We present extensive new \emph{ab initio} path integral Monte Carlo (PIMC) results for a variety of structural properties of warm dense hydrogen and beryllium. To deal with the fermion sign problem -- an exponential computational bottleneck due to the antisymmetry of the electronic thermal density matrix -- we employ the recently proposed [\textit{J.~Chem.~Phys.}~\textbf{157}, 094112 (2022); \textbf{159}, 164113 (2023)] $ξ$-extrapolation method and find excellent agreement with exact direct PIMC reference data where available. This opens up the intriguing possibility to study a gamut of properties of light elements and potentially material mixtures over a substantial part of the warm dense matter regime, with direct relevance for astrophysics, material science, and inertial confinement fusion research.

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Tobias Dornheim, Sebastian Schwalbe, Maximilian Böhme, Zhandos Moldabekov, Jan Vorberger, Panagiotis Tolias. 2024-03-04. Ab initio path integral Monte Carlo simulations of warm dense two-component systems without fixed nodes: structural properties. https://arxiv.org/abs/2403.01979

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