Influence of the diameter and growth conditions on the magnetic properties of cobalt nanowires

Arrays of cobalt nanowires of diameter 23-70 nm were grown by electrodeposition. Their magnetic properties are probed using ferromagnetic resonance. Depending on the solution pH and deposition rate, the orientation of the dense planes of the hexagonal structure can be controlled so that its c-axis is oriented either parallel or perpendicular to the wires axis. In particular, the effects of the pH and deposition current on the structural and magnetic properties are considered and it is shown that the wire diameter plays an important role in the final preferred structure by inducing local changes of the pH within the pores.