Self-Consistent Analysis of Bubble Drive Fields for a Simple Bar

Abstract

In an effort to isolate the essential features required for an accurate description of bubble domain propagation in field access devices, a rather complete analysis of propagation along a bar has been carried out based upon a model first introduced by Copeland and independently proposed by us. Unlike previous treatments bubble size fluctuations are taken into account as are the effects of these fluctuations on the magnetization distribution of the bar. The fields (driving the bubble) calculated in this way are reduced considerably from their values based upon assuming a constant bubble radius. The position dependence of the bubble radius which is obtained for motion along the major bar axis indicates that the operating margin for the bar will be reduced from that for a free bubble. Comparison is made between experimental and theoretical results for a simple bar and the implications of these results are discussed with regard to the basic understanding of device operation and with regard to the analysis of more complicated propagation structures.