High Bulk Spin Scattering Asymmetry in CPP Spin Valves With Alternated Monatomic $[\hbox{Fe/Co}]_{\rm n}$ Superlattice

We confirmed the structural properties of trilayered epitaxial films with AML [Fe/Co]
_n
and Au spacer on Au electrode by RHEED and TEM. A considerably large DeltaRA (2.61 mOmegamum
²
) resistance area product was observed in all metallic current perpendicular-to-plane giant magneto-resistance (CPP-GMR) spin-valve elements by using alternate monatomic epitaxial [Fe/Co]
_n
ferromagnetic layer with IrMn layer on the top. The estimated spin scattering asymmetry coefficient beta and interface asymmetry coefficient gamma was 0.81 and 0.43 plusmn 0.05, respectively. This value of beta is higher than that of Fe
₅₀
Co
₅₀
/Cu laminated with Cu spacer or Heusler alloy which is largest value ever reported at room temperature.