Electrical Conductivity of Hot QCD Matter

TL;DR

This study investigates the electric conductivity of hot QCD matter across various temperatures using a transport approach, revealing significant temperature dependence and high conductivity near the phase transition.

Contribution

It provides a detailed analysis of the temperature dependence of electric conductivity in hot QCD matter using the off-shell parton-hadron-string dynamics model.

Findings

The ratio sigma_0/T decreases in the hadronic phase and shows a minimum near Tc.

Above 5Tc, sigma_0/T stabilizes around 0.3.

QCD matter at Tc is a better electric conductor than copper or silver at room temperature.

Abstract

We study the electric conductivity of hot QCD matter at various temperatures T within the off-shell parton-hadron-string dynamics transport approach for interacting partonic, hadronic or mixed systems in a finite box with periodic boundary conditions. The response of the strongly interacting system in equilibrium to an external electric field defines the electric conductivity sigma_0. We find a sizable temperature dependence of the ratio sigma_0/T well in line with calculations in a relaxation time approach for Tc<T<2.5Tc. The ratio drops in the hadronic phase with T, shows a minimum close to Tc, and becomes approximately constant (~0.3) above ~5Tc. Our findings imply that the QCD matter even at T=Tc is a much better electric conductor than Cu or Ag (at room temperature).