The time-dependent structural and magnetic properties of CoPt nanowire arrays by AC electrodeposition

High areal density CoPt alloy nanowire arrays have been fabricated in anodic aluminum oxide templates by AC electrodeposition. We demonstrate that the AC electrodeposition time in this technique is a very important parameter for the microstructure and magnetic properties of the nanowire arrays. It is found that the mean length of the nanowire arrays, for given electrodeposition conditions, may reach a maximum value at a certain electrodeposition time. As nanowire arrays reach their maximum length, magnetic switching jump in hysteresis loops is observed and it becomes more remarkable with further increasing the deposition time. The corresponding origins of these properties are discussed.