The momentum distribution of the homogeneous electron gas

TL;DR

This paper uses advanced Monte Carlo methods to accurately compute the momentum distribution of the homogeneous electron gas, validating approximate calculations and revealing near-cancellation of complex corrections near the Fermi surface.

Contribution

It provides the first unbiased Monte Carlo calculations of the off-diagonal density matrix and momentum distribution for the homogeneous electron gas across various densities.

Findings

Validation of G_0W_0 quasiparticle calculations

Near cancellation of vertex corrections and self-consistency effects near the Fermi surface

Accurate extrapolation of energies to the thermodynamic limit

Abstract

We calculate the off-diagonal density matrix of the homogeneous electron gas at zero temperature using unbiased Reptation Monte Carlo for various densities and extrapolate the momentum distribution, and the kinetic and potential energies to the thermodynamic limit. Our results on the renormalization factor allows us to validate approximate G_0W_0 calculations concerning quasiparticle properties over a broad density region (1 <= r_s <= 10) and show that near the Fermi surface, vertex corrections and self-consistency aspects almost cancel each other out.