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arXiv:2505.05879 · Physical review. B./Physical review. B

Quantum Monte Carlo study of the quasiparticle effective mass of the two-dimensional uniform electron liquid

Sam Azadi, N. D. Drummond, Alessandro Principi, Rodion V. Belosludov, M. S. Bahramy

Published Aug 8, 2025• 3 citations
arXivHTMLPDF

Abstract

The real-space variation quantum Monte Carlo (VMC) and diffusion quantum Monte Carlo (DMC) are used to calculate the energy bands and the effective mass of the paramagnetic and ferromagnetic two-dimensional uniform electron liquid (2D-UEL). The many-body finite-size errors are minimized by performing simulations for three system sizes with the number of electrons, N = 146 , 218, and 302, for paramagnetic and N = 91 , 139, and 151 for ferromagnetic systems. We consider 2D-UEL to be within the density range 1 ≤ r s ≤ 10 . The VMC and DMC results predict that the effective mass m * of the paramagnetic 2D-UEL at high density r s = 1 is very close to 1, suggesting that the effective mass renormalization due to electron-electron interaction is negligible. We find that m * of the paramagnetic 2D-UEL obtained by the VMC and DMC methods increases by r s but with different slopes. Our VMC and DMC results for ferromagnetic 2D-UEL indicate that m * decreases rapidly by reducing the density due to the strong suppression of the electron-electron interaction.

DOI
10.1103/3wjg-y6qk

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