This work was supported by the Natural Science Foundation of Beijing (Grant No. 2012011).
Ta/NiOx/Ni81Fe19/Ta and Co/AlOx/Co multilay-ers were prepared by rf reactive and dc magnetron sputter-ing. The exchange coupling field (Hex) and the coercivity (Hc) of NiOx/Ni81Fe19 as a function of the ratio of Ar to...