Instability in magnetic materials with dynamical axion field

TL;DR

This paper investigates the instability caused by dynamical axion fields in magnetic materials, revealing how electric fields are screened and converted into magnetic fields, with implications for experimental detection.

Contribution

It demonstrates the screening effect due to dynamical axion fields in magnetic materials and clarifies its physical origin, proposing potential experimental realizations.

Findings

Electric fields above a critical value are completely screened.

Excess energy is converted into magnetic fields.

The physical origin of the screening effect is clarified.

Abstract

It has been pointed out that the axion electrodynamics exhibits instability in the presence of a background electric field. We show that the instability leads to a complete screening of an applied electric field above a certain critical value and the excess energy is converted into a magnetic field. We clarify the physical origin of the screening effect and discuss its possible experimental realization in magnetic materials where magnetic fluctuations play the role of the dynamical axion field.