Temperature dependence of spin pumping in YIG/NiO(x)/W multilayer

Abstract

We report the temperature dependence of the spin pumping effect for Y3Fe5O12 (YIG, 0.9 μm)/NiO (t NiO)/W (6 nm) (t NiO = 0 nm, 1 nm, 2 nm, and 10 nm) heterostructures. All samples exhibit a strong temperature-dependent inverse spin Hall effect (ISHE) signal I c and sensitivity to the NiO layer thickness. We observe a dramatic decrease of I c with inserting thin NiO layer between YIG and W layers indicating that the inserting of NiO layer significantly suppresses the spin transport from YIG to W. In contrast to the noticeable enhancement in YIG/NiO (t NiO ≈ 1–2 nm)/Pt, the suppression of spin transport may be closely related to the specific interface-dependent spin scattering, spin memory loss, and spin conductance at the NiO/W interface. Besides, the I c of YIG/NiO/W exhibits a maximum near the T N of the AF NiO layer because the spins are transported dominantly by incoherent thermal magnons.