(color online) (a) The proposed spin transport processes in the Pt/YIG/Cu/FM structure. Via the spin Hall effect, a charge current ( I in ) in the Pt layer generates a spin accumulation at the interface of Pt/YIG. The s–d exchange interaction at the interface creates a non-equilibrium magnon population and spin accumulation in the YIG layer which drives magnon diffusion. The magnon current excited converts into the spin current in the Cu layer, and then flows into the FM layer. Finally, the spin current in the FM layer is detected by the voltage via the inverse spin Hall effect (ISHE). The M FM can be parallel and antiparallel to the polarization of spin current ( σ sc ) by rotating the magnetic field. We define the polarized direction of the spin current parallel to that of the spin accumulation at the Cu/FM interface. (b) The ferromagnetic resonance (FMR) absorption spectrum measured in SiO₂/Pt/YIG and GGG/YIG samples. (c) The magnetic hysteresis loops measured by AGM for Pt/YIG/Cu/Ni with in-plane and out-of-plane magnetic fields, and for Pt/YIG/Cu/Py with in-plane magnetic field.