Quantitative agreement of Dzyaloshinskii-Moriya interactions for domain-wall motion and spin-wave propagation

TL;DR

This paper demonstrates that the Dzyaloshinskii-Moriya interaction (DMI) has a consistent strength across different magnetic phenomena, confirmed by multiple measurement techniques, clarifying its role in magnetic domain wall and spin wave dynamics.

Contribution

The study shows that DMI strength is consistent for domain walls and spin waves, unifying previous measurements and confirming the compatibility of different DMI measurement methods.

Findings

DMI strength is the same for domain walls and spin waves.

Spin-torque efficiency and Brillouin light scattering confirm DMI consistency.

Supports the unified understanding of DMI in magnetic systems.

Abstract

The magnetic exchange interaction is the one of the key factors governing the basic characteristics of magnetic systems. Unlike the symmetric nature of the Heisenberg exchange interaction, the interfacial Dzyaloshinskii-Moriya interaction (DMI) generates an antisymmetric exchange interaction which offers challenging opportunities in spintronics with intriguing antisymmetric phenomena. The role of the DMI, however, is still being debated, largely because distinct strengths of DMI have been measured for different magnetic objects, particularly chiral magnetic domain walls (DWs) and non-reciprocal spin waves (SWs). In this paper, we show that, after careful data analysis, both the DWs and SWs experience the same strength of DMI. This was confirmed by spin-torque efficiency measurement for the DWs, and Brillouin light scattering measurement for the SWs. This observation, therefore, indicates the unique role of the DMI on the magnetic DW and SW dynamics and also guarantees the compatibility of several DMI-measurement schemes recently proposed.