Momentum distribution functions and pair correlation functions of unpolarized uniform electron gas in warm dense matter regime

TL;DR

This study investigates the momentum distribution and pair correlation functions of unpolarized uniform electron gas in warm dense matter, revealing deviations from Fermi distribution and the emergence of quantum tails and short-range order.

Contribution

It introduces the use of single-momentum path integral Monte Carlo to analyze electron gas, highlighting non-ideality effects and quantum tails in the momentum distribution.

Findings

Quantum tails appear at high momenta in strong non-ideality.

Short-range order correlates with deviations in momentum distribution.

Calculated kinetic and potential energies across various states.

Abstract

In this paper we continued our research of the uniform electron gas, using the single--momentum path integral Monte Carlo method, and studied the momentum distribution functions and the pair correlation functions in the warm dense matter regime. We discovered that the single--particle momentum distribution function deviates from the Fermi distribution and forms so-called "quantum tails" at high momenta, if non-ideality is strong enough in both degenerate and non-degenerate cases. This effect is always followed by the appearance of the short--range order on the pair distribution functions and can be explained via the tunneling through the effective potential wells surrounding the electrons. Also we calculated the average kinetic and potential energies in the wide range of states, expanding our previous results significantly.