Hard magnetic bubbles

After a brief review of normal bubble domain magnetostatics, the static properties of hard magnetic bubbles are introduced by means of some experimental data and the hypothetical micromagnetic structure of the hard bubble wall is described. This structure may be represented by means of a fairly simple analytic function and leads to a good explanation of the static properties of hard magnetic bubbles. The dynamic properties are far more complicated. Simple radial contraction or expansion is straightforward but hard bubble translation involves some very complex behavior. The experimental facts, however, give support to the micromagnetic structure which has been proposed and further support is given by the experimental work which has been done on hard bubble generation. When the problem of what is termed hard bubble suppression is considered, however, it is clear that the hard bubble may still have some unknown features.