GMR in Multilayers with an Alternating In-plane and Perpendicular Anisotropy

The magnetic properties of sputtered ($Ni₈₃Fe₁₇/Au/Co/Au$) multilayers with various thicknesses of Au (0.5 {\leq} t_Au {\leq} 3 nm), Ni-Fe ($1{\leq}t_Ni-Fe{\leq}4nm$) and Co ($0.2{\leq}t_co{\leq}1.5nm$) layers were characterized. An alternating in-plane and out-of-plane anisotropy of the ferromagnetic layers was achieved for the structures ($t_Au{\geq}1.5nm$) showing a weak coupling between the Ni-Fe layers with an in-plane anisotropy and the Co layers ($0.3{\leq}t_Co{\leq}1.2nm$) with a perpendicular anisotropy. For such a structure, a detailed discussion on the GMR effect is presented, relating to the magnetization reversal from a mutually perpendicular magnetic configuration at the remanence to a parallel one at the saturation. An influence of the dense labyrinth domain structure on the magnetoresistance effect is also addressed.