Screening of a test charge in a free-electron gas at warm dense matter and dense non-ideal plasma conditions

TL;DR

This paper investigates how a test charge is screened in warm dense matter and dense plasmas using advanced theoretical models and simulations, highlighting the importance of exchange-correlation effects and the validity of linear response theory.

Contribution

It introduces a detailed analysis of screening in warm dense matter using ab initio Quantum Monte-Carlo data and compares different theoretical approaches for accuracy.

Findings

Long-wavelength approximation is valid under certain conditions.

Exchange-correlation effects significantly influence screening properties.

Screened potentials from linear response theory are applicable for ion dynamics simulations.

Abstract

The screening of a test charge by partially degenerate non-ideal free electrons at conditions related to warm dense matter and dense plasmas is investigated using linear response theory and the local field correction based on ab inito Quantum Monte-Carlo simulations data. The analysis of the obtained results is performed by comparing to the random phase approximation and the Singwi-Tosi-Land-Sj\"olander approximation. The applicability of the long-wavelength approximation for the description of screening is investigated. The impact of electronic exchange-correlations effects on structural properties and the applicability of the screened potential from linear response theory for the simulation of the dynamics of ions are discussed.