Zeeman term for the N\'eel vector in a two sublattice antiferromagnet using Dzyaloshinsky-Moriya interaction and magnetic field

TL;DR

This paper develops a micromagnetic theory to understand how Dzyaloshinsky-Moriya interactions and external magnetic fields influence the dynamics of solitons in two-sublattice antiferromagnets, with implications for spintronics.

Contribution

It introduces a theoretical framework that links external magnetic fields and spin currents to the Néel vector via DM interactions, enabling control of antiferromagnetic solitons.

Findings

External magnetic field and spin current couple to Nél vector in the presence of DM interactions.

Straining the lattice affects Nél vector inertia and dynamics.

The theory suggests new ways to manipulate antiferromagnetic solitons for spintronics.

Abstract

We theoretically investigate the dynamics of solitons in two sublattice antiferromagnets under external perturbations, focusing on the effect of Dzyaloshinsky-Moriya (DM) interactions. To this end, we construct a micromagnetic field theory for the antiferromagnet in the presence of the external magnetic field, DM interaction, and spin-transfer torque. In particular, we show external magnetic field and spin current couple to N\'eel vector in a Zeeman-like manner when DM interactions present, which can be used to efficiently drive antiferromagnetic solitons of different dimensions. Besides, we study the effect of straining the local lattice. It can serve as an external handle on the N\'eel field inertia and thus dynamical properties. Our findings may find applications in antiferromagnetic spintronics.