Quantum Monte Carlo study of the phase diagram of the two-dimensional uniform electron liquid

Azadi, Sam and Drummond, Neil and Vinko, S. M. (2024) Quantum Monte Carlo study of the phase diagram of the two-dimensional uniform electron liquid. Physical Review B: Condensed Matter and Materials Physics, 110: 245145. ISSN 1098-0121

[thumbnail of 2DUEL_PRB_sub2]
Text (2DUEL_PRB_sub2)
2DUEL_PRB_sub2.pdf - Accepted Version
Available under License Creative Commons Attribution.

Download (754kB)

Abstract

We present a study of spin-unpolarized and spin-polarized two-dimensional uniform electron liquids using variational and diffusion quantum Monte Carlo (VMC and DMC) methods with Slater-Jastrow-backflow trial wave functions. Ground-state VMC and DMC energies are obtained in the density range 1≤s≤40. Single-particle and many-body finite-size errors are corrected using canonical-ensemble twist-averaged boundary conditions and extrapolation of twist-averaged energies to the thermodynamic limit of infinite system size. System-size-dependent errors in Slater-Jastrow-backflow DMC energies caused by partially converged VMC energy minimization calculations are discussed. We find that, for 1≤s≤5, optimizing the backflow function at each twist lowers the twist-averaged DMC energy at finite system size. However, nonsystematic system-size-dependent effects remain in the DMC energies, which can be partially removed by extrapolation from multiple finite system sizes to infinite system size. The DMC energies in the thermodynamic limit are used to parametrize a local spin density approximation correlation functional for inhomogeneous electron systems. Our zero-temperature phase diagram shows a single transition from a paramagnetic fluid to a hexagonal Wigner crystal at s=35⁢(1), with no region of stability for a ferromagnetic fluid.

Item Type:
Journal Article
Journal or Publication Title:
Physical Review B: Condensed Matter and Materials Physics
Uncontrolled Keywords:
Research Output Funding/no_not_funded
Subjects:
?? no - not funded ??
ID Code:
226642
Deposited By:
Deposited On:
06 Jan 2025 10:55
Refereed?:
Yes
Published?:
Published
Last Modified:
30 Jan 2025 01:51