Magnon-Dragged Magnetoresistance and Spin Seebeck Effect in YIG/IrMn Thin Films

We report the magnon-dragged magnetoresistance and spin Seebeck effect simultaneously in lateral yttrium iron garnet (YIG)/Ir20Mn80 thin films, which are detected as R-drag and R-SSE, respectively, namely, the nonlocal inverse spin Hall voltages quantified by the injected current. According to their different dependences on applied current, R-drag and R-SSE can be separated as the antisymmetric and symmetric part of the nonlocal signals. By a simple magnon diffusion model, the diffusion length of electrically generated magnons is calculated which is comparable to the values reported in YIG/Pt structures. The low magnetic field and the temperature dependences of R-drag and R-SSE are found to be different, indicating that the origin and transport properties of magnons associated with these two effects are distinct.