The static and dynamic conductivity of warm dense Aluminum and Gold calculated within a density functional approach

TL;DR

This paper calculates the static and dynamic electrical conductivities of warm dense aluminum and gold using density functional theory, incorporating ionization, pair-distributions, and electronic states to understand their behavior under extreme conditions.

Contribution

It introduces a comprehensive first-principles approach combining DFT and a neutral-pseudoatom model to evaluate both static resistivity and dynamic conductivity of dense plasmas.

Findings

Static resistivity data for Al and Au across various compressions and temperatures.

Analysis of the impact of shallow bound states on conductivity.

Comparison of different first-principles methods for optical conductivity.

Abstract

The static resistivity of dense Al and Au plsmas are calculated where all the needed inputs are obtained from density functional theory (DFT). This is used as input for a study of the dynamic conductivity. These calculations involve a self-consistent determination of (i) the equation of state (EOS) and the ionization balance, (ii) evaluation of the ion-ion, and ion-electron pair-distribution functions, (iii) Determination of the scattering amplitudes, and finally the conductivity. We present data for the static resistivity of Al for compressions 0.1-2.0, and in the temperature range T= 0.1 - 10 eV. Results for Au in the same temperature range and for compressions 0.1-1.0 is also given. In determining the dynamic conductivity for a range of frequencies consistent with standard laser probes, a knowledge of the electronic eigenstates and occupancies of Al- or Au plasma becomes necessary. They are calculated using a neutral-pseudoatom model. We examine a number of first-principles approaches to the optical conductivity, including many-body perturbation theory, molecular-dynamics evaluations, and simplified time-dependent DFT. The modification to the Drude conductivity that arises from the presence of shallow bound states in typical Al-plasmas is examined and numerical results are given at the level of the Fermi Golden rule and an approximate form of time-dependent DFT.