Configuration-Sensitive Transport on Domain Walls of a Magnetic Topological Insulator

TL;DR

This paper investigates how the transport properties of chiral edge states at domain walls in magnetic topological insulators depend on the wall's configuration, revealing potential for low-power spintronics applications.

Contribution

It uncovers the configuration-dependent spectrum and transport of chiral edge states at domain walls, highlighting the role of magnetization components in transport behavior.

Findings

Bloch walls cause total reflection of electrons due to degenerate CESs.

Néel walls split CESs, leading to interference-based transmission.

Magnetization components perpendicular to the wall influence transport behavior.

Abstract

We study the transport on the domain wall (DW) in a magnetic topological insulator. The low-energy behaviors of the magnetic topological insulator are dominated by the chiral edge states (CESs). Here, we find that the spectrum and transport of the CESs at the DW are strongly dependent on the DW configuration. For a Bloch wall, two co-propagating CESs at the DW are doubly degenerate and the incoming electron is totally reflected. However, for a N\'{e}el wall, the two CESs are split and the transmission is determined by the interference between the CESs. Moreover, the effective Hamiltonian for the CESs indicates that the component of magnetization perpendicular to the wall leads to the distinct transport behavior. These findings may pave a way to realize the low-power-dissipation spintronics devices based on magnetic DWs.