Spin pumping and the inverse spin hall effect in single crystalline Fe/Pt heterostructure

Spin pumping effect in single crystalline Fe/Pt bilayer has been systematically studied by the measurements of the microwave absorption spectrum and the inverse spin hall voltage detection. The gilbert damping constant of Fe first increases with Pt thickness and then saturates at tPt>1.5 nm. The spin diffusion length can be determined as 1.5±0.4 nm, and the spin mixing conductance is (3.4±0.4)×1019 m-2. The inverse spin hall voltage is quantitatively separated from the spin rectification effect through the measurement of the magnetization angular dependence, and the estimated spin hall angle of Pt is 0.048±0.015, in consistent with the values determined in polycrystalline Pt films.