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 ADeltaR (A is the element size and DeltaR is the change in resistance) was investigated for three kinds of free and pinned layers material, that is, Co90Fe10, Fe50Co50, and Fe50Co50 with half-atomic Cu layers. When the free and pinned layers are 5 nm, ADeltaR is 1.0 mOmega mum(2), 1.6 mOmega mum(2), and 2.9 mOmega mum(2), respectively. Moreover, the dual-type spin valve having Fe50Co50 with half-atomic Cu layers achieved 5.2 mOmega mum(2). According to the free and pinned layers thickness dependence of ADeltaR, the spin-dependent resistance at the interfaces between ferromagnetic layers and spacer Cu is enhanced mainly by changing from Co90Fe10 to Fe50Co50, and the spin-dependent bulk resistance in free and pinned layers is enlarged by inserting half-atomic Cu layers. (C) 2002 American Institute of Physics.