Multiprobe perpendicular giant magnetoresistance measurements on isolated multilayered nanowires

By combining electrochemical deposition into nanopores with electron-beam lithography, we developed an experiment setup to probe the giant magnetoresistance effects with current perpendicular to the plane (CPP-GMR) on isolated nanowires. Here we present four-probe magnetotransport measurements on multilayered Co (55 nm)/Cu (5 nm) nanowires of 100 nm diameter. The multiprobe technique allowed us to measure high GMR ratio on wire segments as short as 500 nm, without any additional contact resistance. We present different magnetic behaviors and GMR ratios depending on the measured segment and the applied field orientation. Results are discussed in terms of the CPP-GMR theory.