Measurement of spin diffusion length in sputtered Ni films using a special exchange-biased spin valve geometry

The authors report the spin diffusion length at 4.2 K in sputtered Ni of l s f Ni = 21 ± 2 nm , and spin-dependent scattering parameters in Ni and at Ni ∕ Cu interfaces. They have employed current perpendicular to plane giant magnetoresistance in both a traditional and an alternative exchange-biased spin valve geometry that inserts a Ni "spoiler" layer into a Py/Cu/Py spin valve. Fits to data of A Δ R vs Ni thickness using Valet-Fert theory [ Phys. Rev. B 48 , 7099 ( 1993 ) ] show good agreement between fit parameters for both sample geometries.