The Chiral Anomaly, Dirac and Weyl Semimetals, and Force-Free Magnetic Fields

TL;DR

This paper explores how the quantum chiral anomaly manifests in condensed matter systems, particularly in Dirac and Weyl semimetals, and links it to force-free magnetic fields that influence current relaxation.

Contribution

It introduces the role of force-free magnetic fields in the macroscopic effects of the chiral anomaly in semimetals, providing a new perspective on their long current relaxation times.

Findings

Chiral anomaly appears in condensed matter systems.

Force-free magnetic fields are involved in the anomaly's effects.

Potential explanation for long current relaxation times in semimetals.

Abstract

The chiral anomaly is a purely quantum mechanical phenomenon that has a long history dating back to the late 1960s. Surprisingly, it has recently made a macroscopic appearance in condensed matter physics. A brief introduction to the relevant features of this anomaly is given and it is shown that its appearance in condensed matter systems must involve force-free magnetic fields, which may help explain the long current relaxation times in Dirac and Weyl semimetals.