Single-momentum path integral Monte Carlo simulations of uniform electron gas in warm dense matter regime

Abstract

In this paper, the single-momentum path integral Monte Carlo method, previously developed for simple quantum systems and hydrogen plasma, is adapted to simulations of the uniform electron gas. The developed method is based on the combination of Wigner formalism and the path integral approach and is able to calculate various thermodynamic values and distribution functions without differentiation of the partition function. Since the exchange interaction between electrons is taken into account by the Gram determinants of the exchange matrix, the fermionic sign problem is reduced significantly, and in the case of coordinate-depending variables, is completely eliminated. The method was applied to study thermodynamic properties of the uniform electron gas in warm dense matter regime. Average kinetic, potential, and exchange-correlation energy were calculated in a wide range of states.