Spin Pumping and Inverse Spin Hall Effect in Platinum: The Essential Role of Spin-Memory Loss at Metallic Interfaces

Through combined ferromagnetic resonance, spin pumping, and inverse spin Hall effect experiments in $\mathrm{Co}|\mathrm{Pt}$ bilayers and $\mathrm{Co}|\mathrm{Cu}|\mathrm{Pt}$ trilayers, we demonstrate consistent values of ${\ensuremath{\ell}}_{\mathrm{sf}}^{\mathrm{Pt}}=3.4\ifmmode\pm\else\textpm\fi{}0.4\text{ }\text{ }\mathrm{nm}$ and ${\ensuremath{\theta}}_{\mathrm{SHE}}^{\mathrm{Pt}}=0.056\ifmmode\pm\else\textpm\fi{}0.010$ for the respective spin diffusion length and spin Hall angle for Pt. Our data and model emphasize the partial depolarization of the spin current at each interface due to spin-memory loss. Our model reconciles the previously published spin Hall angle values and explains the different…