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arXiv · 2305.02274

Static self energy and effective mass of the homogeneous electron gas from Quantum Monte Carlo calculations

Markus Holzmann·Francesco Calcavecchia·David M. Ceperley·Valerio Olevano
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Abstract

We discuss the methodology of quantum Monte Carlo calculations of the effective mass based on the static self energy, $\Sigma(k,0)$. We then use variational Monte Carlo calculations of $\Sigma(k,0)$ of the homogeneous electron gas at various densities to obtain results very close to perturbative $G_0 W_0$ calculations for values of the density parameter $1 \le r_s \le 10$. The obtained values for the effective mass are close to diagrammatic Monte Carlo results and disagree with previous quantum Monte Carlo calculations based on a heuristic mapping of excitation energies to those of an ideal gas.

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Markus Holzmann, Francesco Calcavecchia, David M. Ceperley, Valerio Olevano. 2023-05-03. Static self energy and effective mass of the homogeneous electron gas from Quantum Monte Carlo calculations. https://arxiv.org/abs/2305.02274

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