RADIAL CONTRACTION OF THE FIRST KIND OF DUMBBELL DOMAINS SUBJECTED TOA STATIC BIAS FIELD

On the basis of the ''exercise'' experiment and the phenomenon of ''se lf-shrink'', the behavior of ''less-stable'' IDs (first kind of dumbbe ll domains) in radial contraction under an ''exercise'' bias held, (H- b)(e), was statistically investigated in detail. It was found that the histograms of their stripe-to-bubble transition field, H-sb after exe rcise, become narrower and shift towards the side of lower H-sb with t he increase of(H-b)(e). It illustrates how the less-stable IDs lose pa rt of their vertical Bloch lines under different (H-b)(e). In addition , it was also found that the curve of the upper boundary of these hist ograms, (H-sb)(max) VS (H-b)(e), consists of two segments of straight lines. This discontinuity was proved to be due to self-shrink, and the crosspoint of these two lines is just the lower limit of the self-shr ink region. Furthermore, a series of photographs were taken to show th e effect of radial contraction on less-stable IDs intuitively.