Switching mechanisms of plated wires in external fields

Plated wire switching mechanisms were explored in the case of slowly applied external fields. The main parameter was the helical easy axis angle βHof the Permalloy film. For axial wire (βH= 0) the observed flux reversal proceeded from the ends of the wire toward the center, as shown by pulse timing at different sense coil locations. The pulse timing data were consistent with a transverse domain wall model. The experimentally determined wall mobility was 3×10⁴cm/s-Oe. Observed sense coil pulse characteristics agreed with values calculated from the wall motion model. For nonaxial wire, consistent wall motion phenomena were not observed, and for the main flux reversal occurred simultaneously throughout the film. With increasing βH, threshold fields approached those calculated for rotational switching. The relation of the results to switching applications is discussed.