Axion electrodynamics without Witten effect in metamaterials

TL;DR

This paper proposes a nonlocal metamaterial extension of axion electrodynamics that mimics optical effects like Kerr and Faraday rotation but does not exhibit the Witten effect, enabling new experimental tests of axion-like physics.

Contribution

It introduces a novel nonlocal metamaterial design that replicates axion electrodynamics effects without inducing dyon charges, differing from traditional models.

Findings

Metamaterial exhibits Kerr and Faraday rotation similar to axion materials.

External sources do not induce dyon charges, eliminating the Witten effect.

Potential applications in nonreciprocal optical devices.

Abstract

Artificial media provide unique playground to test fundamental theories allowing one to probe the laws of electromagnetism in the presence of hypothetical axions. While some materials are known to realize this physics, here we propose the nonlocal extension of axion electrodynamics. Compared to the usual axion case, the suggested metamaterial features similar optical properties including Kerr and Faraday rotation. However, the external sources in this structure do not induce dyon charges eliminating well-celebrated Witten effect. We put forward the design of such nonreciprocal non-local metamaterial and discuss its potential applications.