2020/06/05 by Shilei Ding, Andrew Ross, Dongwook Go +10 · 2 citations
Engineering · Physics and Astronomy · #Condensed matter physics #Coupling (piping) #Current (fluid) #Electron #Ferromagnetism #Magnetic properties of thin films #Magnetism #Magneto-Optical Properties and Applications #Materials science #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Spin (aerodynamics) #Spin Hall effect #Spin polarization #Spintronics #Spin–orbit interaction #Torque #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevlett.125.177201
published as Phys. Rev. Lett. 125, 177201 (2020) · 13 pages, 3 figures
arxiv created 2020/06/05 · openalex publication_date 2020/10/22 · arxiv updated 2020/10/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Current-induced spin-orbit torques (SOTs) allow for the efficient electrical manipulation of magnetism in spintronic devices. Engineering the SOT efficiency is a key goal that is pursued by maximizing the active interfacial spin accumulation or modulating the nonequilibrium spin density that builds up through the spin Hall and inverse spin galvanic effects. Regardless of the origin, the fundamental requirement for the generation of the current-induced torques is a net spin accumulation. We report on the large enhancement of the SOT efficiency in thulium iron garnet (TmIG)/Pt by capping with a CuOx layer. Considering the weak spin-orbit coupling (SOC) of CuOx, these surprising findings likely result from an orbital current generated at the interface between CuOx and Pt, which is injected into the Pt layer and converted into a spin current by strong SOC. The converted spin current decays across the Pt layer and exerts a "nonlocal" torque on TmIG. This additional torque leads to a maximum colossal enhancement of the SOT efficiency of a factor 16 for 1.5 nm of Pt at room temperature, thus opening a path to increase torques while at the same time offering insights into the underlying physics of orbital transport, which has so far been elusive.