A Nernst current from the conformal anomaly in Dirac and Weyl semimetals

TL;DR

This paper demonstrates that the conformal anomaly in Weyl and Dirac semimetals induces a bulk electric current perpendicular to temperature gradients and magnetic fields, revealing a novel Nernst effect linked to charge renormalization.

Contribution

It introduces a new mechanism for the Nernst effect in semimetals driven by conformal anomaly, with conductivity determined by charge renormalization beta function.

Findings

Conformal anomaly causes a bulk electric current in Weyl/Dirac semimetals.

The conductivity of this effect is fixed by the charge renormalization beta function.

The effect manifests as a Nernst current perpendicular to temperature gradients and magnetic fields.

Abstract

We show that a conformal anomaly in Weyl/Dirac semimetals generates a bulk electric current perpendicular to a temperature gradient and the direction of a background magnetic field. The associated conductivity of this novel contribution to the Nernst effect is fixed by a beta function associated with the electric charge renormalization in the material.