Induced magnetization of Ru in bcc-(100)-textured adlayers on Fe(100) and exchange-coupled Fe/Ru/Fe trilayers

We report an induced spin polarization in epitaxially grown bcc-textured Ru adlayers on Fe(100) as well as in the Ru spacer layer in exchange-coupled Fe/Ru/Fe trilayers. The measured spin polarization has a maximum value of ${\mathit{P}}_{\mathrm{Auger}}$=(10±2)% at the Fe interface which, in a crude approximation, corresponds to 0.7${\mathrm{\mu }}_{\mathit{B}}$ per atom. The polarization profile in Ru away from the interface is either a steep decrease or a strongly damped rapid oscillation.