Dzyaloshinskii-Moriya interaction energy density for various metal insertion layer in Pt/Co/X/Pt (X=Al, Ti, Ta, W, Pt) by using Brillouin light scattering

Interfacial Dzyaloshinskii-Moriya interaction (iDMI) is an important property for applying new type spintronics devices based on spin-orbit interaction phenomena. Especially, Brillouin light scattering (BLS) is powerful tools to directly observe the iDMI energy.^1,2 In this study, we investigated the iDMI energy density for various atomic number using metal insertion layer by employing BLS measurement. All samples structures are Pt(2.5 nm)/Co(0.9 nm)/X(2.5 nm)/Pt(1.5 nm), X = (Al, Ti, Ta, W, Pt) which are deposited by magnetron sputtering. From systematic BLS measurement, we obtained asymmetric spin-wave propagation along to top (Stokes) and bottom (anti-Stokes) which can determine the iDMI energy density. Furthermore, the iDMI energy densities show consistent result with domain wall motion measurement considered the antisymmetric contribution such as chiral damping.³

References
¹ J. Cho et al., Nat. Commun. 6, 7635 (2015).
² N.-H. Kim et al., Appl. Phys. Lett. 107, 142408 (2015).
³ D.-Y. Kim et al., arXiv:1704.08751 (2017).