Output enhancement of spin-valve giant magnetoresistance in current-perpendicular-to-plane geometry

In this work, we present a suitable material for metal-based spin-valve in current-perpendicular-to-plane (CPP) geometry. The AΔR (A is the element size and ΔR is the change in resistance) was investigated for three kinds of free and pinned layers material, that is, Co ₉₀Fe ₁₀, Fe ₅₀Co ₅₀, and Fe ₅₀Co ₅₀ with half-atomic Cu layers. When the free and pinned layers are 5 nm, AΔR is 1.0 mμm ², 1.6 mμm ², and 2.9 mμm ², respectively. Moreover, the dual-type spin valve having Fe ₅₀Co ₅₀ with half-atomic Cu layers achieved 5.2 mμm ². According to the free and pinned layers thickness dependence of AΔR, the spin-dependent resistance at the interfaces between ferromagnetic layers and spacer Cu is enhanced mainly by changing from Co ₉₀Fe ₁₀ to Fe ₅₀Co ₅₀, and the spin-dependent bulk resistance in free and pinned layers is enlarged by inserting half-atomic Cu layers.