Correlation energy of the spin-polarized electron liquid by quantum Monte Carlo
(2023)
Correlation energy of the paramagnetic electron gas at the thermodynamic limit
Physical Review B American Physical Society 107 (2023) L121105
Abstract:
The variational and diffusion quantum Monte Carlo methods are used to calculate the correlation energy of the paramagnetic three-dimensional homogeneous electron gas at intermediate to high density. Ground state energies in finite cells are determined using Slater-Jastrow-backflow trial wave functions, and finite-size errors are removed using twist-averaged boundary conditions and extrapolation of the energy per particle to the thermodynamic limit of infinite system size. Our correlation energies in the thermodynamic limit are more accurate than previous results. The present diffusion quantum Monte Carlo energies, together with our recently reported [Phys. Rev. B 105, 245135 (2022)] results at low density, are used to parameterize the correlation energy of the electron gas using a functional form that satisfies the exact asymptotic behavior at high density.Discovering Quantum Phase Transitions with Fermionic Neural Networks.
Physical review letters 130:3 (2023) 036401
Abstract:
Deep neural networks have been very successful as highly accurate wave function Ansätze for variational Monte Carlo calculations of molecular ground states. We present an extension of one such Ansatz, FermiNet, to calculations of the ground states of periodic Hamiltonians, and study the homogeneous electron gas. FermiNet calculations of the ground-state energies of small electron gas systems are in excellent agreement with previous initiator full configuration interaction quantum Monte Carlo and diffusion Monte Carlo calculations. We investigate the spin-polarized homogeneous electron gas and demonstrate that the same neural network architecture is capable of accurately representing both the delocalized Fermi liquid state and the localized Wigner crystal state. The network converges on the translationally invariant ground state at high density and spontaneously breaks the symmetry to produce the crystalline ground state at low density, despite being given no a priori knowledge that a phase transition exists.Correlation energy of the paramagnetic electron gas at the thermodynamic limit
(2022)
Low-density phase diagram of the three-dimensional electron gas
Physical Review B American Physical Society (APS) 105:24 (2022) 245135