Fully epitaxial pseudo spin-valves (PSVs) using 10-nm-thick Co2Fe(Ga0.5Ge0.5) (CFGG) ferromagnetic layers and a 5-nm-thick AgZn space layer annealed at 630°C show a large current-perpendicular-to-plane giant magnetoresistance (CPP-GMR) output with resistance-change area product, ΔRA, of 21.5 mΩ μm2 and MR ratio of 59.6% at room temperature. These values are substantially enhanced to ΔRA of 59.8 mΩ μm2 and MR ratio of 200.0% at 10K. The large MR is attributed to the high spin polarization of the CFGG electrodes with the enhanced L21 ordering induced by the atomic diffusion of Zn through the CFGG layers. The CPP-PSV shows relatively large ΔRA of 10.9mΩ μm2 with the MR ratio of 25.6% for the low annealing temperature of 350°C, which is a practically useful feature for read sensor applications.
ASJC Scopus subject areas