Improvement of the yttrium iron garnet/platinum interface for spin pumping-based applications

The investigation of the spin-pumping efficiency in yttrium iron garnet (YIG)/platinum (Pt) heterostructures revealed a strong dependence on the surface processing of YIG prior to the Pt deposition. A pure spin current was injected into the Pt layer using spin pumping and was consequently transformed into a charge current via the inverse spin Hall effect. The resultant electromotive force was used to calculate the spin-pumping efficiency, which varied by a factor of more then 150 for the different YIG surface treatments.