William P. Pratt

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 4.2K in sputtered Ni of lsfNi=21±2nm, 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 AΔR vs Ni thickness using Valet-Fert theory [Phys. Rev. B 48, 7099 (1993)] show good agreement between fit parameters for both sample geometries.

Magnetotransport properties of CoFeB and Co∕Ru interfaces in the current-perpendicular-to-plane geometry

We have investigated magnetotransport properties of CoFeB and Co∕Ru interfaces by measuring the magnetoresistances of sputtered CoFeB-based exchange-biased spin valves and Co∕Ru multilayers on the first antiferromagnetic coupling peak at 4.2K in the current-perpendicular-to-plane geometry. The spin diffusion length lsf and the spin-scattering asymmetry β of Co40Fe40B20 and Co56Fe24B20 are estimated, and the interface specific resistance 2AR* and the interfacial spin-scattering anisotropy γ of Co∕Ru interfaces are constrained.