Spin transport measurements in metallic Bi/Ni nanowires

Abstract

We have performed spin transport measurements in metallic Bi/Ni nanowires using the spin absorption method in a lateral spin valve structure. Although Bi has a strong spin-orbit interaction, the spin Hall angle obtained for Bi/Ni nanowires is about 0.008. The magnitude and sign of the spin Hall angle are much smaller than and opposite to those of Cu-Bi alloys, where skew scattering at Bi impurities is dominant. The estimated spin diffusion length (3 nm) of Bi/Ni nanowires is shorter than that of thin Bi films, which indicates that Bi/Ni bilayers have different spin properties from Bi alone.