Electrical conductivity and charge diffusion in thermal QCD from the lattice

TL;DR

This study uses lattice QCD simulations to calculate electrical conductivity and charge diffusion in thermal QCD, revealing a dip near the deconfinement crossover and providing insights into transport properties of quark-gluon plasma.

Contribution

First lattice QCD calculation of charge diffusion and electrical conductivity across a range of temperatures including the crossover, using anisotropic lattices and the Maximum Entropy Method.

Findings

Diffusion coefficient ~ 1/(2πT) with a dip at crossover

Electrical conductivity and susceptibilities measured for 2+1 flavors

Results inform understanding of quark-gluon plasma transport properties

Abstract

We present a lattice QCD calculation of the charge diffusion coefficient, the electrical conductivity and various susceptibilities of conserved charges, for a range of temperatures below and above the deconfinement crossover. The calculations include the contributions from up, down and strange quarks. We find that the diffusion coefficient is of the order of 1/(2\pi T) and has a dip around the crossover temperature. Our results are obtained with lattice simulations containing 2+1 dynamical flavours on anisotropic lattices. The Maximum Entropy Method is used to construct spectral functions from correlators of the conserved vector current.