Artificial control of layer thickness in Co-Pt alloy multilayer nanowires fabricated by dual-bath electrodeposition in nanoporous polycarbonate membranes

Abstract

We have successfully controlled the layer thickness in Co-Pt alloy multilayer nanowires with a diameter of approximately 130 nm through dual-bath electrodeposition into nanoporous polycarbonate templates. The Co-Pt alloy multilayer nanowires were found to have compositions of cobalt-rich (Co₇₁Pt₂₉) and platinum-rich (Co₁₃Pt₈₇) for various layer thicknesses ranging from 3.3 to 427 nm, as confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations. Both X-ray diffraction (XRD) and TEM analyses revealed a face-centered cubic (FCC) alloy phase corresponding to the Co-Pt alloy in each layer. We could measure the increasing magnetoresistance (MR) ratio by reducing the layer thickness and demonstrate MR measurements resulting from domain wall motion.