Domain wall tilting in the presence of the Dzyaloshinskii-Moriya interaction in out-of-plane magnetized magnetic nanotracks

TL;DR

This paper demonstrates that the Dzyaloshinskii-Moriya interaction causes domain wall tilting in out-of-plane magnetized nanotracks, affecting their dynamics and providing a method to estimate DMI strength via tilt measurements.

Contribution

It introduces an analytical model explaining DMI-induced domain wall tilting and proposes a practical measurement technique for DMI in multilayers.

Findings

DMI causes significant domain wall tilting in nanotracks.

The tilting relaxation time scales with the square of the track width.

The model accurately explains experimental observations in multilayer systems.

Abstract

We show that the Dzyaloshinskii-Moriya interaction (DMI) can lead to a tilting of the domain wall (DW) surface in perpendicularly magnetized magnetic nanotracks when DW dynamics is driven by an easy axis magnetic field or a spin polarized current. The DW tilting affects the DW dynamics for large DMI and the tilting relaxation time can be very large as it scales with the square of the track width. The results are well explained by an analytical model based on a Lagrangian approach where the DMI and the DW tilting are included. We propose a simple way to estimate the DMI in a magnetic multilayers by measuring the dependence of the DW tilt angle on a transverse static magnetic field. Our results shed light on the current induced DW tilting observed recently in Co/Ni multilayers with inversion asymmetry, and further support the presence of DMI in these systems.