Effect of interface number on giant magnetoresistance

Ni(Cu)/Cu, Co(Cu)/Cu, and Ni–Co(Cu)/Cu multilayers with a varied number of interfaces (i.e. bi-layers) were electrodeposited on gold coated quartz discs in a flow channel cell by a potentiostatic dual-pulse plating method. It was found that the giant magnetoresistance of these multilayers increased almost linearly with increase in the number of interfaces. This result confirms that the interfaces play a dominating role in giant magnetoresistance. Comparable samples of these three types of multilayers were prepared under identical electrochemical conditions from appropriate baths. The result showed that Ni–Co(Cu)/Cu multilayers exhibited much higher giant magnetoresistance than Ni(Cu)/Cu, and Co(Cu)/Cu multilayers, which was possibly due to the structural differences between the multilayers.