Absence of spin current generation in Ti/FeCoB bilayers with strong interfacial spin-orbit coupling

Lijun Zhu, Robert A. Buhrman

Published 2020-10-25Version 1

We report a quantitative investigation of the absence/presence of spin current generation by interfacial spin-orbit coupling (ISOC) at a normal metal/ferromagnet (NM/FM) interface. Utilizing the Ti/FeCoB bilayers which are unique for the negligible spin Hall effect and strong tunable ISOC, we establish direct experimental evidence that there is no significant spin current generation at NM/FM interface via spin-orbit filtering effect or Rashba-Edelstein effect even when the ISOC is stronger than that of a typical Pt/FM interface and can promote strong perpendicular magnetic anisotropy. This result also suggests that 3d Ti has minimal orbital Hall effect.