title: Quantum well state induced oscillation of pure spin currents in Fe/Au/Pd(001) systems.
abstract: Spin pumping at the ferromagnetic metal (Fe)/normal metal (Au) interface and the subsequent spin transport in Au/Pd heterostructures is studied using ferromagnetic resonance. The spin pumping induced damping in the Fe/Pd structure is greatly suppressed by the addition of a Au spacer layer in the structure Fe/Au/Pd. The rapid decrease in the interface damping with an increasing Au layer thickness does not correspond to an expectation based on a simple spin diffusion theory in the Au layer. It is possible to account for this behavior by introducing a partial reflection of spin current at the Au/Pd interface. Furthermore, oscillations in the amplitude of spin pumping damping are observed in the Fe/Au/Pd structure as a function of Au thickness for thicknesses less than half the electron mean free path of bulk Au. This new effect indicates a formation of quantum well states in the accumulated spin density in the Au spacer that affect the time irreversible process of spin pumping.
authors.affiliation: Surface Science Lab, Department of Physics, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, Canada V5A 1S6.
authors.forename: Eric
authors.initials: E
authors.lastname: Montoya
authors.affiliation: Surface Science Lab, Department of Physics, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, Canada V5A 1S6.
authors.forename: Bret
authors.initials: B
authors.lastname: Heinrich
authors.affiliation: Surface Science Lab, Department of Physics, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, Canada V5A 1S6.
authors.forename: Erol
authors.initials: E
authors.lastname: Girt