The Dzyaloshinskii Moriya Interaction (DMI) at the heavy metal (HM) and ferromagnetic metal (FM) interface has been recognized as a key ingredient in spintronic applications. Here we investigate the chemical trend of DMI on the 5d band filling (5d^3~5d^10) of the HM element in HM/CoFeB/MgO multilayer thin films. DMI is quantitatively evaluated by measuring asymmetric spin wave dispersion using Brillouin light scattering. Sign reversal and 20 times modification of the DMI coefficient D have been measured as the 5d HM element is varied. The chemical trend can be qualitatively understood by considering the 5d and 3d bands alignment at the HM/FM interface and the subsequent orbital hybridization around the Fermi level. Furthermore, a positive correlation is observed between DMI and spin mixing conductance at the HM/FM interfaces. Our results provide new insights into the interfacial DMI for designing future spintronic devices.
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