Magnetic properties of Au/Co/Ni80Fe20/Co/Au layered structures

The influence of an ultrathin cobalt layer at permalloy/gold interfaces in Au/Ni80Fe20/Au sandwiches and spin-valve (Ni80Fe20/Au/Co/Au)N multilayers on their magnetic and magnetotransport properties is investigated. We show that an effective magnetic anisotropy of Co/Ni80Fe20/Co hybrid structures sandwiched between Au layers can be easily varied by the thickness adjustment of Co and Ni80Fe20 layers. We also show that changes of the anisotropy are mainly determined by the Co layer deposited on Au. On the other hand, the influence of Co layer deposited on Ni80Fe20 is relatively small. The use of hybrid layers in the spin valve MLs with alternating easy plane and perpendicular anisotropy in consecutive ferromagnetic layers leads to significant changes of their rnagnetoresistance effect.