Quantitative accordance of Dzyaloshinskii-Moriya interaction between domain-wall and spin-wave dynamics

Abstract

The magnetic exchange interaction is one of the key factors governing the basic characteristics of magnetic systems. In contrast to 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 under debate, because largely distinct strengths of the DMI have been measured for different magnetic objects, particularly chiral magnetic domain walls (DWs) and nonreciprocal spin waves (SWs). In this paper, by carefully examining the measurement principles, we demonstrate that both the DWs and SWs experience the same strength of the DMI. The key factor in this demonstration is to identify the appropriate experimental conditions by excluding all possible artifacts that causes additional undesired symmetric and antisymmetric contributions in chiral DW dynamics. The present demonstration, therefore, verifies the universality of the DMI between different magnetic dynamics as an intrinsic exchange interaction and also, guarantees the compatibility of several DMI-measurement schemes recently proposed.