We have investigated the effect of magnetostatic interactions on the m
agnetization reversal behavior of Ni,,Fe,, flat wire arrays using magn
etoresistance (MR) measurements. The wires are fabricated from films o
f thickness 500 Angstrom. As the separation s of a wire array of fixed
width w = 2 mu m is increased, a crossover from the behavior characte
ristic of an interacting wire array to that of a single isolated wire
is identified for s/w similar to 1. For the interacting limit, s/w les
s than or equal to 1, a marked reduction in the coercive field occurs
as the spacing of wires of fixed width are decreased. The shape of the
MR response to fields applied along the hard axis is also found to be
strongly dependent on the interwire separation. We attribute this beh
avior to the effect of interwire dipolar interactions. MR measurements
were also made as a function of the orientation of the applied field
relative to the axis of the wire, in order to investigate how the shap
e anisotropy affects the magnetization reversal process. In mu-size wi
res we find that ''one-jump'' switching of the magnetization can occur
according to the orientation of the wires with respect to the applied
field.