MAGNETOSTATICALLY INDUCED GIANT MAGNETORESISTANCE IN PATTERNED NIFE AG MULTILAYER THIN-FILMS/

Thin film multilayer structures consisting of two permalloy layers sep arated by Ag spacers show little or no giant magnetoresistance in thei r as-deposited state, due to a predominantly ferromagnetic interlayer exchange coupling that does not oscillate in sign with variations in t he Ag spacer thickness. Upon patterning these films into arrays of dot s and other geometries with micron scale features, however, antiferrom agnetic coupling and giant magnetoresistance are observed due to magne tostatic interactions between layers that are induced at the edges of the patterns. In this letter we present our experimental results and d iscuss their relevance as magnetoresistive sensors for magnetic record ing heads and other applications. (C) 1995 American Institute of Physi cs.