Anomalous Hall effect in dense QCD matter

TL;DR

This paper explores the anomalous Hall effect in dense QCD matter, revealing its similarity to Weyl semimetals and identifying unique contributions from axial anomaly.

Contribution

It demonstrates that dense QCD matter with a dual chiral density wave exhibits a nonzero anomalous Hall conductivity due to Weyl points and axial anomaly effects.

Findings

Dense QCD matter shows Weyl points in its energy spectrum.

The Hall conductivity is proportional to the Weyl point separation.

An additional contribution from axial anomaly is identified.

Abstract

In this letter, we investigate the anomalous Hall effect in dense QCD matter. When the dual chiral density wave which is the spatially modulated chiral condensate appears in the medium, it gives rise to two Weyl points to the single-particle energy-spectrum and then the anomalous Hall conductivity becomes nonzero. Then, dense QCD matter is analogous to the Weyl semimetal. The direct calculation of the Hall conductivity by way of Kubo's linear response theory gives the term proportional to the distance between the Weyl points. Unlike the Weyl semimetal, there appears the additional contribution induced by axial anomaly.