Anomalous conductivity in holographic QCD

TL;DR

This paper investigates anomalous conductivity behaviors in holographic QCD, revealing two distinct charge carrier types and perfect conduction under specific electromagnetic conditions, driven by the axial anomaly.

Contribution

It introduces a detailed holographic analysis of conductivity in the Sakai-Sugimoto model, highlighting novel anomalous transport phenomena linked to the axial anomaly.

Findings

Conductivities suggest two different charge carrier types.

System acts as a perfect conductor with parallel electric and magnetic fields.

Anomalous behaviors originate from the axial anomaly.

Abstract

We compute the longitudinal and Hall conductivities in the parallel phase of the Sakai-Sugimoto model with a transverse magnetic field. We find that the conductivities behave as if the charge of the system is made out of two different types; one behaves as charge carriers flowing through a dissipative neutral medium, while the other does not feel the dissipation. We also investigate the case of an electric field parallel to the magnetic field and find that in this case the system behaves as a perfect conductor. Both of the unusual behaviors stem from the axial anomaly.