GIANT MAGNETORESISTANCE OF CURRENT-PERPENDICULAR EXCHANGE-BIASED SPIN-VALVES OF CO CU/

We present the first measurements of the specific resistance change, A Delta R, with increasing Co layer thickness, t(Co), of current-perpen dicular (CPP) exchange-biased spin-valves (EBSVs) of Co and Cu. A Delt a R grows about as predicted for a long spin-diffusion length in Co un til about t(Co) = 20 nm, after which it grows more slowly than predict ed. Possible reasons for this deviation from prediction are considered , including a short spin-diffusion length in Co.