Universal charge and current on magnetic domain walls in Weyl semimetals

TL;DR

This paper explores the universal charge and current behaviors at magnetic domain walls in Weyl semimetals, revealing their dependence on chemical potential and Weyl node splitting, and proposes a method to manipulate domain walls via electric fields.

Contribution

It uncovers the universal properties of charge and current at domain walls in Weyl semimetals and links them to the chiral magnetic effect, offering new ways to control magnetic textures.

Findings

Bound states around domain walls include Fermi arc states with linear dispersion.

The localized charge and current depend only on chemical potential and Weyl node splitting.

Proposed manipulation of domain wall motion using external electric fields.

Abstract

Domain walls in three-dimensional Weyl semimetals, formed by localized magnetic moments, are investigated. There appear bound states around the domain wall with the discrete spectrum, among which we find "Fermi arc" states with the linear dispersion. The Fermi arc modes contribute to the electric charge and current localized at the domain wall, which reveal a universal behavior depending only on chemical potential and the splitting of the Weyl nodes. This equilibrium current can be traced back to the chiral magnetic effect, or the edge counterpart of the anomalous Hall effect in the bulk. We propose a new way to manipulate the motion of the domain wall, accompanied with the localized charge, by applying an external electric field.