Fabrication and magnetic properties of Co/Cu multilayer nanowire arrays

Co/Cu multilayernanowire arrays embedded in anodic alumina (AAO) template were successfully prepared by dual-bath electrodeposition technique. SEM and TEM indicated that the Co/Cu nanowires were regularly spaced and uniform in shape with lengths of about 20 mu m and diameters of 80 nm. The bilayer thicknesses of the two samples were 50 nm and 200 nm respectively. XRD test indicated that the Co and Cu grew in their (hcp) and (fcc) polycrystal structures, respectively. VSM test indicated that nanowire arrays had apparent magnetic anisotropy. The giant magnetoresistance (GMR) ratio of the nanowire arrays with the bilayer thickness of 50 nm was about -75%, whereas the bilayer thickness increased to 200 nm, the nanowire arrays had not GMR effect.